Patch for a rip in the lining of a down jacket

When i worked at a tailor shop, we had single side fusible backing to repair the liners of the tuxedos. It came in black or white, was placed on the inside of the tear, ironed into place and then, if it was a large tear, hand stitched.
    The easiest thing to do in this situation if you don't need to stock up on this type of product, is to take the jacket to a dry cleaner or tailor shop and get a quote on the repair.

If you want to buy the interfacing, look into Pellon Shape-Flex Interfacing. Instructions are below the image.

Quickly looking online, the example above is the closest thing I can find to what I remember using without actually touching it. It was malleable and had a knit texture to it, this example says woven, so the texture may be different. You'll want to find something that matches your repair fabric. The fabric shop may sell facing by the foot or yard. (editorial - You really do not need an entire bolt unless you're going into the repair business. A little goes a very long way.)

Instructions: You only need to cut as much as you need to hide the tear. The facing goes inside the tear, adhesive side touching the lining. Then iron with a press cloth to protect the polyester. As stated above, if it is a large area, it's good to hand stitch the tear for extra security.

For a hole, place the facing inside the hole, adhesive side against the lining, then place a small piece of matching fabric over the facing, use a press cloth when ironing. Then hand stitch if necessary.


As you know, the vibration of the chime is what causes the sound. Within that vibration are peaks and troughs of vibration, but there are also nodes where the vibration is barely, if at all, noticeable. If you don't tie down the chime at exactly one of these nodes, you'll attenuate your sound and cause buzzing anyway.

Instead of tying your chimes, think about laying them in a way that makes them act like you want without the problems you don't want. This, believe it or not, has been figured out by makers of xylophones and marimba.

For example, a xylophones has lots of tuned steel slats that are struck by mallets, just like you want to do with chimes. They do bounce a little, but that's addressed by having a hole in one or both ends and a pin loosely in the hole preventing it from moving in an undesirable way. These slats are also resting on felt or other cloth risers at their nodes to prevent buzzing and damage from striking too hard & bounces. (I've left the image large so the cloth strips can be easily seen.)

Also, most chimes for music are held in place by either loose cords or a rod. Granted, these are also generally vertically mounted, but it's something to think about, since you are going the opposite direction in that you want to tie them securely down.

I'm not recommending a product or website, but if you look at how someone else makes something similar, you'll notice that the chimes appear to not be held down at all. It would be interesting to look at this from the ends of the chimes to see if there's a cord running across the tubes, but just hidden. The supports here look like rubber to prevent buzzing.

https://www.hayneedle.com/product/20inwoodstockpipedreamwindchime.cfm

On the other hand, a single chime seems to be supported and held down by the same attachment device. It's a bad pic, but the support looks like a rubber O-ring, also presumably to prevent buzzing.

https://www.hayneedle.com/product/woodstockzenergywindchimesingle.cfm


The arch is not a painted part of the painting, but a physical part of the room in the Santa Maria delle Grazie above which the mural can be found:

source


What are food safe finishes for woodworking projects, e.g. turned bowls?

There are many different kinds of finishes that are food safe. It turns out most finishes once dried or cured are food safe to one level or another.

Most finishes that cure are only food safe after they have finished curing which, sometimes can take quite a while, days, weeks, for some months.

Many of the food oil finishes are very food safe, peanut and walnut oils for example.  However, these are not hypoallergenic, since people with nut oils can react to the finish in the wood.  Though people with extreme allergies could even react to the walnut wood itself.

Natural waxes are excellent food safe finishes that are also hypoallergenic.  Bees wax is a good one and apparently paraffin is also a good one, even recommended for cutting boards, which means with the knife in contact with the top it, you are sure to get some mixed in with the food.

My favorite wax is Carnuba wax, it is claimed to be the most hypoallergenic wax out there and it is also the strongest/toughest natural wax known.


Embedding a neodymium magnet inside a forged/melted aluminum enclosure

The melting temperature of a magnet is irrelevant because it loses it's magnetation long before melting.

Have a look at this site and you'll see that the maximum working temperature of neodymium magnets is approx. 230°C for the most heat resistant magnets. This site explains why the magnets get permanently demagnetized by heat.

The only way to embed a magnet into aluminum and keep it intact is to prepare a cavity in the aluminum and insert the magnet later (when the metal cooled down to working temperature). If you want to coat the magnet, either use galvanization or a different material.


How Can I Create the Metal Comb of a Music Box?

In order for the "tines" on your comb to ring brightly, you must begin with spring steel. You may use a flat piece of steel and cut the teeth into it or use a long length of quality steel bar such as a metal yard rake.
I used a length of sewer cleaning flat bar--cheap and very good steel. I simply cut it into 15 pieces about 3 1/2" long. You must secure these onto or between heavy steel blocks. Cut at an angle to make each tooth a little shorter than the last and bring them each to a point for plucking. Using a tune meter ($10.00 at any guitar store), pluck the shortest tooth and grind or sand off a little of its surface on the back until it is the correct note. Follow in order until each tooth is in tune. Remember: making each tooth either thinner or shorter raises the pitch of that tooth.
Don't let anyone tell you this will not work! I have built four machines so far with great results. Go for it.


Effective ways to practice drawing anatomy?

The reason drawing the human form is such a challenge is how our brains work, we have a symbolic representation of what humans "look like" in our minds but that is not how bodies actually look in real life. So the struggle in life drawing is to draw as the eye sees the form, not as the mind records it. Understanding human anatomy and lots of practice (which includes lots of failure in the process) is the key.

Get a good book on anatomy and drawing technique. We used "Drawing the Human Form" by William A. Berry at my college. There are others. These will show you the relationship between the structures of the body and the forms they create. The skeleton, the musculature over it, and the skin that wraps it, they define the form a body takes. How these forms react to light, where highlights and shadows fall, that is what you want to put in your drawings. Studying these books will help you understand that connection.
Attend life drawing sessions. Nothing beats drawing a live human being for what you are after and few things are more challenging. Often there will be a teacher or other artists guiding these sessions that can work with you to correct your technique. Try to be loose, use soft drawing media like charcoal on cheap paper, don't be fussy. Also pay attention to where the light is coming from in relationship to the body and use that to model the form. You could try getting friends and family to pose for you, but that can increase the challenge as it becomes more personal.
If you can, take a course on drawing the human form at a local school or artists collective.


If you are running into trouble turning words into pictures then add a "scribble" to your notes as well. Later, after waking up and the dream imagery has gone away, you can look for the imagery you describe from your text within the lines of the scribbles.

Think of the scribble as a thumbnail sketch of what you think your mind's eye had seen.  Not what you see with your eyes but what your mind had dreamt up moments before while asleep and dreaming.

The processes is called "Surrealist Automatism".

Surrealist Automatism, also known as automatic drawing, is a processes where the artist suppresses conscious control over the drawing process and allows the subconscious to freely take over. The arm is given free control over the drawing instrument. Normally this is extremely hard to do but seeing how you are looking to try this moments after waking it should make the processes easier for you.


Why is wearing a mask recommended when carving antler?

I think @matt's response is exactly correct, but I wanted to add a bit more to it. There are two concerns about inhaling dust--the size of the dust particle and the chemical composition of the particle.  There are lots of articles on-line that talk about how dust inhalation causes problems, but I will summarize this one from the Canadian Centre of Occupational Health and Safety.

In general, your body has lots of systems designed to move dust particles back out of your lungs when you breathe them in. The first line of defense is a layer of mucus--the dust gets caught in this mucus and then these teeny hairs called cilia all wave together (imagine a crowd doing "The Wave," or someone crowd surfing at a punk music venue) to move that dusty mucus out of your lungs and into your throat where you can cough it out (or swallow it--blech).

Some very small dust particles can get past the mucus and cilia and end up in the very tiny air sacs in your lungs called alveoli. When this happens, your body produces cells called macrophages that surround the dust particles, and physically move it to the cilia so that they can do their job and move the particle out of your lungs. The lungs also produce a protein that neutralizes the dust particles.

But, if you are inhaling a large amount of dust at one time, or over a long period of time, it can overwhelm your body's ability to produce microphages.  The dust particles accumulate in your lungs and reduce your ability to breath deeply--I imagine it something like a roof drain pipe clogged with leaves.

And some dust particles are composed of chemicals that interact with your body in nasty ways--apparently cigarette smoke actually paralyzes the cilia--so even if your microphages were working perfectly, it wouldn't matter. And there could be pathogens, bacteria or mold spores in the dust that could make you ill.

So, in general, if you are working on something that is likely to create small dust particles like woodworking, carving antlers, using dye powder to dye fabrics, working with ground glass for fusing, etc., you want to limit the amount of dust that you inhale into your lungs.  Each exposure may not be dangerous on its own, but combined exposures over the course of your life can really build up and cause problems.


Probably the best thing is the acrylic paint uses for plastic models followed by a couple of coats of gloss acrylic varnish. This will be pretty durable and should give a good result. They paint system sold by Games Workshop is pretty good quality.

You will want to thoroughly clean the surface before applying the paint alcohol is probably the best thing for this. It will also help of you scuff up the surface with wire wool although this does mean that you will probably need to paint the white parts as well.

You may also want to mask of the fur around the eyes (assuming they aren't removable) you could do this with a piece of thin plastic cut from a drink bottle, food packaging or similar, Cut a large disk and cut a slit in it so you can slip it behind the eye.


What about those small plastic clear round takeaway restaurant containers?

Image from AliExpress

They are clear.
Have a lid (also clear)
Are wedge shaped (making it easier to insert into the end of the tube)
With the lid accessed from the outside you could then change what's in the kaleidoscope.

Or you could pre-make different containers with different confetti and glue the lid down. The kids could then swap different containers into the tubes as they want.


How can I make egg-tempera that doesn't deteriorate?

Egg tempera is well-known to be quite stable under normal circumstances once it has dried.
However, the fresh tempera can easily go bad, especially in warmer conditions:

To prepare the tempera paint, dry pigment was mixed with water and egg
yolk. The problem of preserving the colours during the painting process
was handled with different methods. Egg tempera has a propensity to
putrefy rapidly, especially in warmer climates. Although egg yolk is a
perfect emulsion, when mixed with pigment and water, its natural
emulsifying property tends to break down.*

To counter this effect, different methods were used within different traditions:

The Italians added the sap of fig trees [fig tree clippings or latex, see source below] into the egg yolk paint binder, as recommended by Cennini.
In Germany, flat beer was sometimes added to preserve the paint.
Russian icon painters added kvass ["a fermented beverage commonly made from rye bread" ✝] to the yolk. Kvass was added in an amount equal to the egg yolk and in place of adding water.
Sometimes a little vinegar was added to the binder,
or gum tragacanth was mixed with the egg yolk.*

I know that vinegar is still commonly used to slow down the deterioration process.

It should be noted, however, that these retarders are not necessary for tempera to remain in good condition - works in pure tempera (i.e. only pigment and egg yolk) have survived in splendid condition, of which an alleged ultimate example would be the so-called Pozzolatico Panel by Jacopo del Casentino from the beginning of the fourteenth century:

(Click for full and larger version)
Apart from the wonderful state of the painting layer itself, it has a double-layered varnish in very good condition: one layer is egg white diluted in water, the second so-called vernice grassa, which is mastic diluted in turpentine, and results over time in a typical cool grey film.

Cennino tells us that tempera was made by using egg yolk as a binder
for the pigments, and then diluting the mixture in water. At the end,
the painter had to add a coating of a different type to protect the
painting from dust and moisture. Although virgin tempera is already
relatively strong, it is still tender. The painters of that time were
aware that vernice grassa should not penetrate the tempera because
it would spoil the light refraction. Therefore, between the tempera
and the final covering of vernice grassa, a thin covering of egg
white was added as soon as the painting was finished. ‡

The layer of egg white shields the underlying layer of tempera from moist, dust, and interactivity with other coatings, by making it impermeable.

Reversely, the condition of the tempera is naturally also dependent on the qualities and chemical compound of the ground layer. While egg tempera stabilizes quickly, it can still be influenced by these during the drying process.
Cennini goes into a lot of detail concerning the work on panel or ancona, specifically intended for gilding. Here are the steps in a simplified (but still maybe needlessly extensive) way:
The panels "should be made of a wood which is known as whitewood or poplar, of good quality, or of linden, or willow". The wood has to be completely dry, and all defects (greasiness, knots, buds, nails) have to be dealt with thoroughly.
Then the panel needs to be glued before a layer of strips of linen and "a size made of clippings of sheep parchments" is applied to it. This has to dry for two days.
The entire panel will now be covered meticulously with layers of a mix of the size and "gesso grosso, that is, plaster of Paris (originally: "coarse plaster, of Volterra"), which has been purified and sifted like flour".
After drying, another set of layers is applied of a mix of this size and "a gesso which is called gesso sottile; and it is some of this same gesso, but it is purified for a whole month by being soaked in a bucket". This gesso is also used for making relief on the panels.
This again has to dry, the longer the better.
The final step in preparing the ground is to scrape it down until it "comes out like ivory".
Preparatory sketches on this panel are made with charcoal, fixed with ink.
A somewhat different approach is that used in Russian iconography:

Icon panels were made from dried wood boards, typically linden or
alder wood, onto which a cross-hatch pattern was incised with a sharp
tool and a size made of animal skin or sturgeon fish was applied. Over
this a layer of linen cloth soaked in the size was laid down known as
pavoloka (паволока).
The composition of the levkas [a recipe for the ground] was usually gypsum, chalk or a combination of the two minerals mixed with animal skin glue diluted with water. To this mixture was frequently added a small amount of honey. [...] After the ground was thoroughly dry, it was moistened with water and polished with a pumice stone. *

An important conclusion we can draw from this, is that the surface the egg tempera will be applied to, should be thoroughly dry.

Lastly, having very little impact, the pigments themselves affect the quality of the paint, especially by influencing the drying process.

Although pigments do not have, in general, a large effect on
temper ageing, they can slightly accelerate the process of
degradation of proteins, and perturb their identification. It is known
that copper pigments interfere with the identification of tempers. ❧

Sources:
- Cennino Cennini - The Craftsman's Handbook - Dover Publications, New York, 1960. Transl. Daniel V. Thompson.   Here is an online version that is one page number behind on my edition.
‡ Del Serra, Alfio. “A Conversation on Painting Techniques.” The Burlington Magazine, vol. 127, no. 982, 1985, pp. 4–16. JSTOR (preview).
❧ Helena Valente Vargas - Study of the aging of binders in proteinaceous media by high performance liquid chromatography (p. 6 offers a very interesting table showing discolourment of the pigments over time).
♦ Antonella Casoli, Michela Berzioli, and Paolo Cremonesi - The Chemistry of Egg Binding Medium and Its Interactions with Organic Solvents and Water.
* Review of Medieval Italian and Russian Tempera Painting Technique.
✝ https://en.wikipedia.org/wiki/Kvass
° https://en.wiktionary.org/wiki/parget


Soft pastel is literally the most difficult "painterly" media to protect. Generally speaking, the appropriate way to protect pastels is with a so-called shadow box, where the paper or board is floated above the backing plate of the frame and still has air-space to the glass. (See my drawing below.)

This is a pretty material-intensive method, but it serves to isolate the pastel from touching anything, including the glass. You have probably noticed that applying fixative to soft-pastels will change them, dulling the whites etc.

There is, in my opinion, no cheap way to protect pastel drawings, but I do have two suggestions.

Find cardboard boxes with clear plastic inserts, like gift boxes where you can see inside them.
Take a high resolution photo and print them at the local drugstore or at an online service. Frame them as you would any photo.

The second option is probably the only way to cheaply conserve your pastel.


How can I safely prepare bones for crafts?

Any bones which are obviously clean and free form any residual soft tissue shouldn't be too much of a problem. With skulls you obviously have more cavities to work about but if the outer surface is clean when you find it it is reasonable to amuse that the interior is too.

Once the bones are cleaned of any soil etc a wash with dilute hydrogen peroxide should effectively sterilise them without damaging the bone.

Obviously with any organic material of unknown origin you can never say it is 100% safe but equally it is ether practical or desirable to attempt to live in an aseptic world. For carving bones sensible precautions wold include wearing a dust mask (if using abrasives or power tools) and maintaining sensible hygiene in you work area. Similarly sealing your finished carving with oil, wax or lacquer should be effective in making it safe to display.


What are the specifications of the paper required for pencil color drawings?

There are several characteristic for a paper that should influence your choice :

The weight

The higher this value will be the thicker and the studier the paper will be. It is usefull to have a rather high value, because you will be able to erase or burnishing, without completely destroying your paper. Personnaly I thing that having 200 gsm is enough, but maybe if you erase a lot and have hard pencils it would be a good idea to aim higher.

The tooth

It designs the microscopic grains on the paper that hold the pigments. Thus a paper with more tooth, will be able to receive more layers. But it is possible to apply several layers on paper with less tooth, but your first will have to be very light, otherwise the paper will saturate fast. On the other hand if the paper is very rough, you will have a different finish than on a smooth surface.
For watercolor papers it depends of the denomiantion from the smoother to the rougher, you have : Hot press, Cold Press, Rough.

Acide free paper

If you want a paper that last longer (less yellowing for example) you can use an acid free paper, but since you use student grade colored pencils, it not really necessary.

Products

You can try some hot press watercolor paper, and maybe cold press if you feel like you can't layer as much as you wish. If you have some smooth bristol at home, you can also try to work on this paper. Personnaly my favorite paper is the Stonhenge drawing paper, but it may be expensive. You can also use Canson Mi-Teintes if you want to draw on a colored surface, but becareful one side is too rough.

You can find here a comparison of different papers, but the colored pencil used are artist grade. It can give you an idea of the finish of your drawing depending on the paper you chose. Comparison of papers


How to maximize the post-dried life expectancy of flowers?

If a flattened flower is okay for your purpose; you could adopt techniques from herbarium-sheet preparation. Keep the flowers in a fold of a diary or hardbound old notebook. Change their position every day (if flower is larger or jucier, you could use newspapers since entire papers should be changed at few to 6 hours interval at start days, latter intervals will increase gradually). At first day the flower (or anyother plant matter) would become soft and weak. Gradually it would become hardened like potato chips. Sunlight in way is very helpful.

After completion, paste them with fevicol or such polymer glue in thin-amount ((since your work is permanent, feel free to fevicol or such. Botanists use  gum or glue instead so that specimen could be taken out later-on and dissected)), and some simple biology box tools like a pair of needles, a forceps and a scalpel with neat and clean, gently stretched way. (if don't have biology box, don't worry, other art tools and household things could be used). After completion of your artwork, dry it under hard sunlight. could take help of hair dryer. but never a iron. Any spray or coat is not used in a herbarium sheet, but if you wish to spray laquar or such; please make sure it is properly dried. Because if the water is locked it will ensure quick deteroration.

If you wish make it insect-proof; could use book-binding gum with copper sulfate... but that is toxic as well as gums and glues may take more time to get dried, so isn't preferable. If you wish, could wish clothings-naphthalene but then you have to keep it out of reach of children.

But in a herbarium-sheet preparation technique; the flower-colour is not retained.

P.S. Herbarium sheet preparation technique already used by students for beautiful artworks especially with ferns, sedges etc. but rarely with flowers.


Is it possible to restore the plastic on a pickguard without removing a signature on it?

Please do not soak the pickguard in peroxide! That's highly likely to remove or damage the permanent marker signatures since peroxide is a bleaching agent. You might be able to carefully clean around the signatures using a mostly dry small tool with peroxide or other cleaning solution on it, but even then you would run the risk of some of it bleeding over onto the permanent marker and doing harm. I wouldn't recommend even trying it!

Instead, since you're planning on framing it anyway, consider adding another layer of glass between the pickguard and the glass in the frame. Then stain that additional glass layer strategically with a thin wash of paint or ink or dye to visually even out the pickguard that will be beneath it. Colors can be powerful. Try washes in various colors and shades of the same color to see how the pickguard looks through the stained glass. The eye can be fooled nicely with the proper colors.

The advantage to that approach is that you can experiment without any risk to the pickguard, and you can clean off what you did if you don't like it and try something else (glass is very friendly that way). You should be able to achieve the desired result without changing the pickguard in any way.


At a minimum what would I need to repair a fracture in a gold pendant?

In my jewelry making course way back in 2000, heating metal for soldering required actual flame... a torch. You wouldn't want to do this with the equipment you have at all. It's a totally different process.

There are two different soldering methods in jewelry making: soft solder and hard solder. While many craft-y projects can be assembled using soft solder (that is, solder that can be melted using a soldering iron), working with silver and gold requires hard solder and a torch. There's a guide to it here.

  "Hard" solders are alloys that melt at slightly lower temperatures than the corresponding metal pieces to be fused. Silver and gold jewelry require hard soldering. Copper, brass, and bronze components can also be fused with hard solders. In addition to requiring flux, hard solders generally also require the use of pickling solutions to clean and remove surface oxidation from the finished piece.

This matches my experience pretty much exactly. While we largely worked with base metals - copper, brass, nickel silver, etc - we did all of our soldering using a torch setup, flux, and pickling solution.

  Metal workers typically use oxy/propane or oxy/acetylene torches with hard solder, but many soldering tasks can also be achieved with butane torches. Use a butane torch to solder jump rings, create ball-end head pins, make custom wire links and chain, create small bezels, fuse together small metal components, etc.

For your little project, based on this section, I'd guess that you could get away with using a butane torch but you'd also need to buy gold solder (to match the color), flux, pickling solution... which was always kept warm in an old Crock Pot.


How can I fuse separate, small pieces of ABS plastic that can withstand pressure?

PlasticWeld is a hand-mixable, fast-setting epoxy putty that forms a durable bond to most major plastic types. *After mixing, it forms a polymer compound that can be molded or used to build up and repair just about anything made from plastic. When cured, it can be sawed, drilled, carved, sanded and painted. PlasticWeld has a 20-25 minute work life; functional cure occurs in 2-3 hours. PlasticWeld cures to an off-white color, is rated at a tensile strength of 350 PSI. Does not adhere to polyethylene, polypropylene or some other plastics. Test for adhesion first.

Great for:
Rigid & Semi-flexible Plastic
ABS, PVC & CPVC Pipes
Automotive Trim & Bumpers
Fiberglass Parts
Vinyl Siding

Found at most automotive and hardware stores:Products link to O'Reilly's

DETAILED DESCRIPTION
Repair and rebuild any rigid and semi-flexible plastic including ABS, PVC and CPVC
Bonds instantly
Superior strength
Will not shrink or pull away
Rebuild automotive trim, fiberglass parts and vinyl siding
ADDITIONAL DETAILS
Set Time (hr): 0.25 Hour
Cure Time (hr): 3 Hour
Volume (ml): 60ml
Volume (Oz): 2 Ounce
Cure Color: Off White
Material: Epoxy Resin
Color: Off White
Solvent Resistant: Yes
Temperature Range (Deg F): -67 To 300 Degree
Strength Rating (psi): 350 psi
Strength Rating At 400 Degrees (F): 350 psi
Water Resistant: Yes
Waterproof: Yes
Weatherproof: Yes
Type: Epoxy Stick

EDIT: Adding instructions here so it is not lost in comments.

INSTRUCTIONS
CUT:
Remove required amount of putty.
MIX:
Thoroughly knead putty with fingers to a uniform color.
APPLY:
Press putty firmly to the surface to be repaired.


Why does the thread keep snapping on my Silvercrest sewing machine?

Many sewing machine issues can be resolved by simply removing the thread and re-threading it. Your machine's manual should have a diagram showing how to insert the thread. Even if you're sure you already know how to thread the machine, find that diagram and follow it step by step. You may find that you've been missing a step, or putting the thread in the wrong place.
Even if you don't figure out what the issue was, sometimes re-threading will solve it anyway. The thread may have been getting snagged or dragging somewhere along its path, and by re-threading it, you may fix that issue.
As you feed the thread, watch for any places that seem rough, or slots that seem tight. Manually pull the thread back and forth through each slot and around each turn, checking to see if it snags or tugs anywhere. It should pull smoothly through/around each point.
Here's a troubleshooting guide for the Silvercrest SNM 33 B1 machine. It basically says what I mentioned above, but it has diagrams for how to re-thread.
Make sure the bobbin is inserted in the correct orientation, as you can see in this snipped from the troubleshooting guide. My machine (which is a different brand) will work when the bobbin is in the wrong way, but the thread snags and snarls much more frequently.

Also check to make sure your needle is not bent, blunt, or damaged. If you can't tell, swap in a fresh needle just to be sure.


What is the difference between a mural and street-art?

Generally a mural is any art which is applied directly to a wall, often a painting or drawing although the term can also be applied to sculptural reliefs.

Street art is a bit more general and is usually used for art which takes place in public spaces. As well as semi-permanent media like murals this can also apply to performances or temporary media like pavement drawing. The term can also be applied to things like portrait drawing which take place on the street although in this sort of context the term 'street artist' might be more appropriate than street art.

Historically graffiti generally implies casual drawing of painting on public or private structures often without permission. However it is also associated with a set of painting styles using aerosol cans, often on quite a large scale. As with all definitions of art what is and is not intended as 'art' is debatable and mutable.

In many western cultures street art has associations with urban subcultures and political protest although again, it is becoming increasingly mainstream and there are a few examples, notably Banksy where it it pretty much part of teh mainstream elite art market...although again what this actually means is a whole other debate in itself.

The actual style and medium can vary a lot. From the context of the question it seems like you are thinking mostly about images painted on walls etc but most cultural forms, dance, poetry, music, theatre ect  have some 'street' version which may be either more of less 'underground' or be part of more mainstream cultural as seasonal or festival events.

Consider also Yarn Bombing and Guerrilla Gardening

There is also some overlap with public art (typically large scale sculpture) although street art implies something less formal and less permanent. Similarly 'street' tends to imply a more urban setting.


Alternative to Shapecrete - moldable concrete that is workable like clay

This question is premised on a particular cement product that could be handled like clay but appeared to dry looking like poured concrete.  It turns out that is not the case.  So the "simplest" answer is that the question is based on bad assumptions.  However, depending on actual requirements, the objective of the question could have full or partial solutions.
ShapeCrete
Start with the product that triggered the question.  The example you saw on the ShapeCrete web site is easy to misinterpret.  After a lot of investigation, it appears it was an anomaly, and not quite what it seemed to look like.  Getting into all the details would be tangential to this answer.  But if you want to exploring that example, what it appeared to be and why, the technique used, or how to reliably get readily-visible bubbles in ShapeCrete or a similar product, that would be great fodder for a separate question.
The key points are these:

It's a cement product.
It can be mixed to be pourable, in which case it will have the bubbles of poured concrete but not the surface texture.
It can be mixed to handle like clay, in which case the result will look like clay.

It is no longer available.  But if what it does is useful to you, yes, there are alternatives.  I found an equivalent competing product: SculptCrete.  There may be others.  Note that neither ShapeCrete nor its competitors will dry to look like poured concrete when used like clay.
DIY Mixes
There are also DIY cement mixes that handle like clay.  They typically have a surface texture like concrete rather than like clay.  So a DIY mixture may be close enough for some applications, or could be a good starting point to replicate the look of poured concrete.  Do a search on "diy concrete clay".  You'll find videos like Making a Concrete Mix that Works Like Clay and How To Make Concrete Clay At Home.  Each recipe will have different characteristics, depending on the purpose.
Concrete appearance
The characteristic appearance of poured concrete comes from two aspects:

Surface texture (smooth and grainy)
Surface bubbles

The surface texture comes from the component sand of a certain particle size.  That can be easily replicated by using a mixture that contains sand of similar size.  Clays use a much smaller particle size and result in a smoother surface.  However, you can start with a concrete mix and modify it to handle more like clay (most of the DIY concrete clay mixes), or start with an air dry clay and add some sand to make the surface texture similar to concrete.
Bubbles are a characteristic of poured concrete.  Pouring it into a mold results in some of those bubbles being on what will become the surface when it is demolded.
By its nature, clay-like materials do not have surface bubbles, at least of a size that looks like poured concrete.  You can do things to get bubbles into the surface.  On material that is wet, soft, and barely clay-like, it's easier to do and there are more ways to do it.  On material that is firm, dense clay, there are limited ways to modify the surface to produce bubble pocks, but it can be done.  If the material only has to look like poured concrete and doesn't have to actually be concrete, there are more options.
Basically, the requirement for handling like clay is the opposite of the requirement for surface bubbles.  The more clay-like it is, the fewer options there are for getting bubble pocks into the surface.  It's worth examining the requirements for a specific project in detail because there are trade-offs that can make the project a lot easier if some of the requirements aren't critical.
How to get a specific kind or type of clay-like material to look like poured concrete would be a discussion for another question.


Will gold leaf adhesive work on flexible TPU plastic?

I've never tried to gild a phone case before, so take this with a grain of salt...

I would suggest using the same methods you'd use for exterior gilding: prime the surface with several layers of primer, sanding in between; apply an exterior-grade gold size (also called "oil size" or "solvent-based size"); wait for the size to dry to the appropriate level of tackiness; apply the metal leaf; after a bit more drying, brush off any loose gold; after allowing the size to fully cure (could take a week or more), apply a sealer to prevent tarnishing.

If you don't want to go to such extremes (trying to buy oil size in quantities small enough for your purposes would probably be difficult), it might be sufficient to use primer + your existing gold adhesive (probably PVA-type) + leaf + varnish/sealer. For the primer, try to find a paint that's specifically meant for plastic: you want something that's guaranteed to stick to the plastic, and then your gold adhesive will stick to the paint (or at least it should), and then the metal leaf will stick to the gold adhesive, and then (after everything has cured as fully as it ever will, but before oxidation has set in) seal the metal leaf both to protect it from abrasion and to prevent tarnishing.

Regardless of what specific steps you follow, you may end up with a phone case that's noticeably thicker than it was before. Make sure to mask off any areas that shouldn't get thicker, i.e. any prongs/thingamabobs that make the case stay on the phone, the inside of the case, the holes for the camera/power cord/headphones/switches and buttons, etc.

The other caveat is that, unlike IKEA furniture, your phone case is probably not flat. This means that you will be gilding around a curve, which is more difficult than just covering a rectangular flat area. You will end up with gaps, and even after doing your best to fill them in, you'll see the seams, and some gaps will just be too small to fill but not small enough to be invisible. (This is where genuine gold leaf would make things easier: it will stick to itself, allowing you to fill in gaps totally invisibly.) Depending on the effect you want to achieve, choose your primer and/or adhesive color to either contrast with the gold (a red Armenian bole color is traditional for this) or blend in as much as possible (i.e. yellow).


Metallic Spandex

See some samples at Google Images


Other resources I can suggest are these:

http://www.1001fonts.com/stenciled-fonts.html
https://www.urbanfonts.com/fonts/stencil-fonts.htm

Try out which suits your design best.
Check out sites that have "free" download option for flexibility.

If not free, you can redo/recreate some letters you need in Adobe Illustrator/Corel Draw, just get the letters you need.


It sounds like you are talking about steel rule dies.

These use a flexible or semi-flexible strip of steel sharpened along one edge. This is embedded in a backing (sometimess fibre/particle board) usually sitting in a thin profile-cut slot which supports the steel cutting edge.

You can buy the prepared steel stock and make the dies yourself and there are also manufacturers who will make custom dies to your specification and they are relatively inexpnsive, at least by the standard of dies in general.

They are quite well suited to cutting resonably soft materials like paper, leather, and textiles. They work best when used with some sort of press.

I have made these myself in the past with some success when used with an arbour press. I cut the profile out of MDF with a fine coping saw and used thin shim stock to make the blades. This isn't quite as hard as the proper die stock but will just about work.


Can Rustoleum wood stain bleed through a mounted photograph?

Depending on the type of paper (and more importantly the type of glue you use) the stain will probably attack the paper over a long period of time.

Isolating the stain is a good idea, and I can recommend the following approach.

First give it a solvent-based coat of transparent varnish. This will protect the stain from the outside world and because of its similar composition will bond to it rather well. Let dry.
Now give it a water-based coat of transparent varnish, this will enable it to bond with the next two layers. Let dry.
Now use another coat of the water-based varnish and float the photo paper on it. Let dry
Use one last coat of water-based transparent varnish to encapsulate the photo.

A couple words of warning: test the water-based varnish to make sure that it doesn’t damage your photo, watch out for bubbles and always ventilate!


Depending upon where you live, you could put it out in the Summer sunshine.  Might take a while, but sunlight seems to fade everything that I expose to it, including the sunshade fabric which is specifically designed to resist UV fading.


Painting Clear Gesso Over Acrylics or Spray Paint - is clear gesso really clear?

For your black piece, a slightly better alternative would be black gesso, since clear gesso is slightly cloudy. Liquitex and Golden make it.

For your smaller piece -

If want to draw on your surface and need a lot of tooth, then clear gesso will help. Clear gesso is very toothy, and too rough for some applications.

If you're afraid that your new layer of paint won't stick to the spray paint, then try matte medium, which has a little tooth. Or you could mix matte medium with clear gesso to get the properties you want. Or you could sand the slick parts.

Your previous layer of acrylic paint should not be dissolved or washed away by the gesso or matte medium, unless it's not fully cured, or you thinned the acrylic paint with too much water. Use THIN coats of gesso or matte medium, and minimal brushing.

It might make glossy areas less glossy, and porous areas more wet looking.

It is slightly opaque, but not noticeably cloudy in two thin layers.


Does epoxy's final bond strength depend on its rated cure time?

I've been told by the proprietor of the local hobby shop that long-cure epoxy adhesives will be stronger than short-cure. I was told at the time that it has to do with the lower heat generated by the long-cure, but my research today suggests nothing of the sort.

The few links I pursued indicated that long-cure epoxies remain in a semi-liquid state for a longer period (duh) which allows the cross-linked molecule strings to increase in length, when compared to short-cure epoxies.

I have noted that when using 5 minute cure time epoxy adhesive, it will sometimes fail under lower stress conditions than expected, while in a similar mechanical configuration, the 30 minute stuff holds up.

In all of these epoxy references, including those for fiberglass and carbon fiber applications, it is noted that full strength will require 24 hours or longer.

One of the forum posts I discovered (radio control model building) provided an anecdote in which the OP discovered the 15 minute epoxy adhesive would shrink and crack and become brittle under conditions that did not cause similar problems for the 30 minute formulation.

I was unable to locate any solid technical papers covering research. It appears anecdotal and also my personal experience.


What do 'woolen spun' and 'worsted spun' mean?

Woolen spun and worsted spun are references to the way the yarn is actually spun in the spinning process.  Worsted spun yarn includes individual fibers that are facing in many directions, whereas woolen spun has all of the fibers facing in the same direction before the yarn is spun and they remain much more parallel in the final spun singles. The process of spinning the two types of yarn is different as well, but less important to know if you are the end user of the yarn.

Woolen spun tends to incorporate more air between the individual fibers, so a woolen yarn will weigh less than a comparably thick yarn that is worsted spun.  The additional air also helps heat retention, so garments made from woolen spun yarn can be lighter weight and still warmer than those made from a comparably thick worsted yarn.

However, because the individual fibers don't overlap each other the way they do in a worsted yarn, woolen spun yarn doesn't hold up over time as well as a worsted spun yarn.  It is also more likely to pill.

As for when to use which one--well the opinions on that question are all over the place.  I suggest googling "woolen vs. worsted yarn" and you will read a hundred different opinions.  But, in general, I would avoid woolen spun yarns for projects that are going to get alot of rubbing, pulling, tons of wear.  Be cautious about using a woolen spun yarn for something you are going to put on a kid, for example.  But a shawl would be the perfect use for a woolen spun yarn, because you are looking for additional warmth with minimal weight when you make a shawl, AND it is less likely to be subject to the type of usage that will cause pilling.

One confusing element is that worsted in this context means the fashion in which the fibers are prepared (and spun), whereas worsted is also used in many parts of the world to indicate yarn of a specific thickness. These two definitions have absolutely nothing to do with each other--so you could spin a woolen yarn that is worsted weight, and confuse the heck out of everyone. You could also spin a non-wool fiber using the woolen spin technique (I think--better spinners than I feel free to disagree), and then have a cotton yarn, for example, that is woolen spun.  Super confusing.

Another important concept--singles vs. plied yarn.  When you first spin fiber into a strand of yarn, you have what is called a single.  The individual fibers are held together by adding twist into them--the amount of twist determines how strong the actual yarn is.  But think about what happens if a child sitting on a swing spins around a bunch of times and puts a twist in the ropes holding the swing.  They actually built up alot of energy in the ropes as they created that twist, and let go, the ropes release that energy by unspinning really quickly.

Singles yarn is called "energized" because it has a similar inherent energy in it.  When you work with singles yarn, your final product will be much less consistent, even and smooth, because even after it is worked, the singles yarn is continually trying to release some of that built-up energy.

When you ply yarn, you take a number of singles (I think three plies is the most common), and twist them together in the opposite direction from the twist you used to combine the fibers into a single strand. The aim when creating a plied yarn is to balance the residual energy from the singles without actually untwisting the yarn and having the individual fibers fall apart. When you ply yarn, you are specifically trying to create yarn that is balanced--you should be able to drop a strand of plied yarn and it will not try to untwist in either direction.  Working with plied yarn tends to create smoother, more even and more regular final products.

The last issue I will mention is the directionality or type of twist in your yarn. Yarn can have an S twist or a Z twist.  This describes the direction the yarn was plied (and is compared to the direction of the center element in these two letters). If you hold up a piece of yarn and look closely, you will see that the individual threads (or singles) spin in a direction that either looks like an S (they start at the top left of the strand and move diagonally to the bottom right) or a Z (they start at the top right and move diagonally to the bottom left).  The technique that you use for knitting or crocheting can interact differently with the different twists--some techniques might twist the yarn in such a way that it comes partially untwisted as it is worked.  Because twist is what gives yarn its final strength, this can actually have an impact on the strength of your final piece.

This is a pretty complex issue, and I don't know enough about it to be able to explain all of the permutations here.  My suggestion is to try and determine what type of technique you use for knitting (are you a thrower or a picker? Continental vs. English?) and/or crocheting (I don't know the equivalent terminology for crocheting, but I know that as a kid I used to crochet in a way that twisted the yarn less than I do know as an adult).  Once you know what to call your technique, you can start searching for that technique in combination with "S or Z twist" and see what people say about which works better in which situation.


Judging from the images of the example you linked to, I assume the shells have been softened and shaped, which is most obvious around the edges (as they fold around the borders). What I found about softening capiz shells is that heat and/or a (chemical?) solution are used.

Here is a paper on the softening process, but it's likely automatically translated from Chinese to English, and kind of hard to read, but this is what I take away from it: the shells have to oxidize for 11-12 hours using a chemical process, and then, through applying pressure, the cracked shell can be shaped.
Here is another paper, speaking of softening the shells of crustaceans for edible purposes by soaking them in a mix with glacial acetic acid (which is sold, among other places, on Amazon):

  Soaking the crabs at temperatures from about 80 to 212 degrees Fahrenheit, in an aqueous solution containing from about 2% to 25% by weight of glacial acetic acid, until the shells become acceptable soft as determined by tactile examination.

Hopefully, these papers might provide a starting point to experiment with the softening of shells.

However, since that process is likely quite hard to perform - since little information on it is readily available - as an alternative, I suggest casting the shells in a clear epoxy resin (see also here).

Lay out the shells in a pattern you like on a flat surface large enough to contain the size of the tabletop. Set up a border around the area, and slowly and carefully add an epoxy resin. After curing, you can saw off the excessive part of the edge, and grind it down to a nice smooth surface.

Depending on the height or thickness you want the top to have, you might consider adding an additional layer cast in the same fashion.

For more detailed instructions I suggest reading this article (I won't go into the details, since I only want to address the specificity of your question as it is quite broad in scope as it is).


How to prevent beading in aluminum palette

The aluminum aspect of the palette has little bearing on the problem describe, but the enamel surface is the biggest concern. Enamel, unless otherwise modified, is going to be smooth and glossy, the worst circumstance for your undesirable water beading.

You aren't far off to consider to abrade the surface, but baking soda is not particularly abrasive. It's more likely to dissolve and become useless for the purpose.

High grit count sandpaper may be faster and more effective. Consider to look for 400 or 800 or even 1200 grit sandpaper, most often called wet/dry sandpaper. Hardware stores and big box stores will usually stock such products, as will painting stores, but for a higher price.

You'd place the palette in a stream of gently flowing water and scuff the surface of the enamel while keeping the sandpaper wet. The water prevents the sanded material from clogging the grit and may perform other tasks that escape my alleged mind at the moment.

You'd be able to angle the palette to a light source and observe the extent of the abrasion while performing the scuffing. Additionally, you can observe how the water beads on the untouched area while flowing over the portions you've sanded.


What magnification do I need to read an inscription on a gemstone?

It should be possible to calculate this, but note that it will depend on your eyesight as well, and the contrast you can get (directional lighting may help)

If you look at how many characters there are in a typical inscription (I've seen up to about 30 for synthetic diamonds online;this is lovely to be a worst case), and how much space they fit in, you can work out the character spacing. 30 characters in one row of 5 mm would be 0.17 mm character width including separation. 30x would make this equivalent to about 5 mm which is very large print. Normal text is more like 1-2 mm per character, which you'd achieve with a 10x jeweller's loupe. If you're collecting gemstones you probably want a good loupe anyway, and if this doesn't allow you to read the inscription, it should at least allow you to count the characters and rerun my calculation.

I do suggest getting a decent loupe. Mine is only a cheap thing, but at 10x still allows me to resolve features down to that sort of scale with decent eyesight; reading inscriptions of about twice the size I calculated above (on electronic parts) is trivial. I don't have a gemstone, let alone an engraved one, to test for certain.

You could also resolve this with a decent camera with a macro lens or extension tubes. If you have access to an SLR a cheap set of extension tubes would allow you to record the inscription. Holding everything steady and focussing can be more of a challenge


How to clean a plastic eraser?
My personal choice is to use a blank piece of paper and "erase the dirt" from the eraser onto the paper. If you have shaped your eraser with a knife or sandpaper, this method will be the least destructive.
There are other methods found online. Most curiously, I found a WikiHow article "3 Ways to Clean an Eraser" that describes using a borax solution to clean an eraser. The article is mostly aimed at rubber erasers, but I don't know if the borax solution would work on plastic erasers.


How do I prevent chalk pastel from getting smudged?

Once you've finished your work, if you need to protect it from being smudged, use Fixative Spray that is made for specifically this purpose. Hairspray will also work in a pinch.

Only do this once you're finished though - since it will make it near impossible to add more chalk once it's done. If you need to transport unfinished work, do so in a tight folder, with another blank piece of paper placed carefully over the top of your work (with a bit of masking tape around the edges for extra security).


What type of paint to repair my wooden veneer?

Matching paints and colours can be a science in itself. No matter what you do the chances of it match perfectly are close to none. I don't have much advice to offer when it comes to painting. But...

Not an answer to your exact question but wanted to offer a different suggestion then painting. Why not just patch the veneer? One the first obvious questions would be I can't find something that matches. You don't really need to anyway.

There are plenty of people who patch veneers are both old an modern furniture whether the end result is meant to be a simple repair or to add an accent.

It does not have to be a simple square patch either. You have the opportunity to make something truly special and unique. In it simplest form find some existing veneers, thin scrap wood etc.

Severally simplified steps

I don't image you are going to do this anyways.

Cut a shape you would like that compliments the damaged area. It is actually preferred that it be slightly thicker than what you are replacing.
Remove any extra remaining veneer are the area. Use the patch you created in the previous step as a template.
Clean the "void" and fill in if damage is severe. (You could use plastic glue in your case)
Glue in place.
Sand down. Card scrapers are useful here but not something everyone has. Careful around the existing veneer.
Finish as desired.

There are many tutorial examples out there but here is one where a table with a cigarette burn was patched and finished.

Mid Century Table Veneer Repair


How to intentionally fray curved edges in fabric?

You have the right idea. Sewing near the edge but leaving the actual edge raw will achieve a frayed edge. Things to keep in mind:

This will only work on a woven fabric, not a knit.
Most importantly, not all edges will fray equally on a circle shape. Because of the nature of a woven fabric, the threads are horizontal and vertical. Certain places around the circle (mostly when you hit the bias area), the fraying will change or may not show up at all.
The weave does matter. If the fabric has a very open weave, it may not have a very frayed look, but look like loose threads.


The point of kintsugi is to emphasise rather than hide damage in an aesthetically pleasing way.

The Japanese word Kintsugi translates more or less as ‘joining with gold’, and

  The story of Kintsugi is said to have begun in the 15th century when Japanese military commander Ashikaga Yoshimasa broke one of his beloved Chinese tea bowls and, disappointed with the shoddy repair job it was treated to, urged Japanese craftsmen to come up with a more pleasing method of repair. (Source)

If you wish to remain true to the tradition, precious metal (powdered gold, silver or platinum) is mixed with clear resin or lacquer. This enables you to see the gold or silver colour from the metal clearly.

There would be no reason why you cannot mix the metal powder into ceramic paste, but you would not necessarily see the metal in the join as clearly.

I have seen some people fix the pottery with ceramic paste then paint the crack with gold ceramic paint to emphasise. Painting the joins, or using pigment powders as you suggest, is not a true traditional Kintsugi piece as no precious metals are being used. But, it still plays on the tradition of wabi-sabi (an eastern philosophy of living that finds beauty in the damaged or imperfect).

For more on this, see https://www.bbc.co.uk/programmes/articles/326qTYw26156P9k92v8zr3C/broken-a-pot-copy-the-japanese-and-fix-it-with-gold


Formula for strong but lightweight paper-mache

I've always used slightly diluted white PVA glue (just enough water to make it runny enough to soak paper in). Recently tried using kitchen roll, which was durable and held its shape well. Tissue paper (as in artistic, not toilet roll!) is also nice - very lightweight, and can also go directly on top of chicken wire, if you preferred to make a framework with the wire. Careful if you're using dyed paper though; sometimes the colour leeches out of the paper, or just runs everywhere.

EDIT

Hopefully the photo shows it a bit more clearly. It's pretty tough, and holds paint really well. It smoothed fairly nicely, but we were in a bit of a hurry (and the bobbly texture actually worked quite well with fruit!)


The "planes of the head" are the simplification of the constant curving of the head into areas that share a similar orientation. Meaning, take the curved surfaces of the head and flatten those surfaces to get the fewest flat areas while preserving the basic volume of the head. Think of the forehead, it is basically one big area that faces in a certain direction. The tops of the cheeks another area that generally faces in one direction, the temples another. Identify and outline these areas to get your "planes of the head".

Loomis is suggesting that there is a formulaic approach you can take to do this that results in the same general set of flat areas that to together make up a angular, flat paneled version of a human head. Then you have simplified shapes that will be easier to put into perspective and serve as the under-drawing for a smoother final version.

You need to be able to draw an arbitrary flat plane shape (a polygon) from different perspectives. If you can draw a given triangle or trapezoid from different points of view then to draw a head you would use the same technique with the collection of arbitrary flat plane shapes that you have extracted from the head and memorized according to Loomis.


How do I repair the binding of the book where the spine of the cover is too wide?

It looks like a low-budget operation using a one-size-fits-none cover stock, or they got the wrong size covers.  The cover spine is too wide.  As long as it's stiff, it will continue to pull on the page seams.  I would try these two steps:

The original glue location is visible where it came apart.  Put a narrow bead of glue in the same location (Elmer's Glue should be fine).  If you put down too much, spread it from the original location toward the spine and wipe off any excess (when you press it closed, you don't want glue being squeezed between the cover overlay and the front page).
Lightly close the cover and immediately open it again to spread some of the glue to the other side.  If excess glue squeezes onto where you don't want it, wipe that off with a slightly damp rag.  Leave the cover open for a few minutes for the glue to mostly soak into the paper and any wiped areas to dry enough to not be sticky.  Close the book, making sure the cover is aligned as it originally was.  Put a little weight on top, like another heavy book, and let it dry for at least a few hours.

Soften and curve the spine so it's flexible.  The spine will try to pull the pages apart if it's stiff and flat.  Between the spine and the covers, there's an indentation front and back.  Put a heavy duty rubber band in that indentation to compress the covers against the pages.  Then open the book in the middle and lay it flat, pages down.
The spine should jut out in a curve.  If it doesn't, find something rod-shaped that you can push between the spine and the pages to push the spine out into a curve (just big enough to introduce a curve, not so big that it tears the glue joint holding the pages in).  Use your fingers to compress and roll the curve all along the length and from cover to cover to train it into a curved surface instead of a flat one, and to soften it a little.
Then close the book and with the rubber band still on, hold the book spine-down, press it against a surface like a desktop, and roll it from side to side (putting pressure on the front and back corners).  Compress the indented area to make the indentation and the bend between the indentation and the spine more pronounced.
These actions will reduce the tension on the pages so the cover doesn't try to pull the pages apart.


How does the step transition in this origami construction occur?

You have to pull out the paper as far as the vertical split visible in step 15. At the same time it will "wrap around" to show the other side of the paper.

You could also look at it like this: if in step 15 you completely unfold the white part, you will see a small square with a crease pattern such as for the bird base. Now, along the precreased lines, collapse one diagonal half of the square into a half of the bird base, and the other half of the square leave folded in two. This produces your step 16.


Am I going about learning to draw the wrong way?

You say

  Things in the real world aren't 2-d, they're 3-d objects. I'm not
  making a 3-d object when I draw, I'm making a bunch of lines on a 2-d
  piece of paper that will create the optical illusion of being a 3-d
  object.

and you are absolutely right. That's what drawing is.

If you want to start thinking of 3D objects as 2D I suggest you  use only one eye when you draw or generally examine objects.

You can also take pictures of objects and draw from them (with the help of a grid on top, if needed). Or, better, place a grid frame and draw looking through it (this technique was previously used for acquiring accurate perspective, but I think it will work well to get you to think of 3D objects as flat):

*try it for smaller drawings though (A4 or A5) and without grid on the actual paper

Getting familiar with the basics of perspective would also help a lot.

Where shade falls shouldn’t be too confusing to you if you generally think of objects as 3D. If you don’t get too technical about it, light beams travel straight from the source of light and illuminate the surface they fall right on. The rest is in shade.

About sculpture, it is not necessarily an expensive undertaking. You can dig and refine your own clay. Plaster is relatively cheep too.


Cutting out the truck and trees would be pretty straight forward.  Just find equivalent vector art in whatever format your laser likes.  Online trace and format transformation websites are available to help with that step.

To make the truck and trees stand up, you will need to add a square tab to the bottom of each tire and to the base of the tree's trunk.  This tab will fit into slots which you cut in the disk portion of your project.  Inkscape is a free vector editing software which is good at making these kinds of modifications.

Just make sure to measure the thickness of the wood you are cutting all this from, and use that as the width of the slots you are cutting in disk.  That way, the tabs which you have added to your upright pieces will fit snugly into those slots.


What to use as the background for a self-made scratchboard (or scrapeboard)?

What you are looking for, the base for a scratchboard, is Clayboard. It is available in art stores and online... search for art panels.

You can make clayboard a number of ways:

The Jimmy Arborough site has a recipe for rabbit skin glue based
ground. Rabbit skin glue is tricky in that it requires hot water, cooling time, and is made out of rabbits. He uses about a 1:1 ratio of water to clay in his recipe.
The white glue and plaster method is popular and easy. Use plaster of paris not drywall compound to get a brighter white.
You could also mix kaolin clay or plaster of paris with regular acrylic ground and apply that.  Here start with 1/3:1 ratio of clay to base, adding more clay to get the absorbency/feel you desire.

With any of these methods you can whiten the base by adding Titanium White.

Once you have a ground, apply it in multiple layers to masonite or heavy paper board in layers, letting each layer dry between applications. You will need a number of layers (5-10) to get the right thickness. If the board warps, try painting the back with an X of the same ground to pull it back into shape. When the board has dried thoroughly, lightly scrape the surface with a knife to remove any blobs or burrs, then sand smooth with a fine grit sandpaper.

To finish the scratchboard, take a dry and clean clayboard, brush or spray with India Ink, again layering until you have the tone you want. The result should be a smooth hard surface, ready for carving into.


This is non-hardening plasteline, also known as plastecine.

For the record, although it is labeled as children’s modeling clay, I do not trust it to be non-toxic. Having worked with exactly this product in the past, I did find it to be great when building seals in damming walls of casting molds. If you want it to be harder, you can cool it / freeze it. This will not harden it, as you are only performing a state change in the oils / paraffins that are used to keep the mass malleable. I would be very cautious of overheating it, as you are likely to generate toxic fumes.


You need a Brush Cleaner and Restorer formulated for this task. There are a few of these available, only in art supply stores; you'll want to check with the ones around you to see what you can purchase.

If you are in the United States, Winsor & Newton makes a widely available product I have used with great results; it's formulated for dried acrylic and oil paints, but I have also used it to dissolve away dried latex (house) paint, as well as years-long set dry varnishes. With this product, you'll let the brush soak up the solution, checking periodically to monitor the progress. In a low quality brush, it may end up damaging it by damaging any glues holding the bristles in place in the ferrule, but at the point you're using a restorer on a brush, it's typically ruined anyway, so there's no risk in trying. In my experience, I've only had one or two brushes lost this way out of dozens.

Unfortunately, this particular product is not available outside of the United States, but other companies do make similar products that you'll be able to find by asking your friendly local art supply shop. The employees there should be able to recommend a product to you with which they're familiar.

Ultimately, the best option is to avoid needing a restorer in the first place; take proper care of your brushes, cleaning them right away instead of letting paints dry in them. Avoid getting paint up into the ferrule, and dry them bristles down so paint and water don't soak down into the ferrule and cause damage.


How can I prevent watercolor paper from buckling?

To prevent the paper buckling/cockling you pre-stretch it, That is you wet the paper and tape it down to a rigid board with gum strip. I generally use a wooden drawing board that I made in work shop practice 50 odd years ago. Note masking tape does not work as well as gum-strip for this as it does not adhere very well to wet paper.

You paint onto the stretched paper and only cut it free from the gum-strip when finished.

Heavier paper (say 300+ grams per square meter) usually does not cockle when you paint on it using water colour technique (do not regard this as a challenge, I'm sure you could get it to cockle with a wet enough technique).


Material that can be cut / carved and doesn't react with silicone

Cover the object in petroleum jelly (aka Vaseline) first, you may also try adding paint thinner to it, to make the coating smoother.

Using different types of construction silicone may give different results. Some of these contain glue and other components that make the cured silicone stick better to different surfaces. So I guess the simplest and cheapest neutral silicone is the best.

EDIT: some say that adding the corn starch to silicone makes the molds dry faster. Not sure if it makes the silicone less liquid though.


What paints could I use on nylon fabric?

I don't have specific experience painting nylon fabric, but as a starting place for you, Dharma Trading Company has a tutorial for painting and/or dying silk that may apply to your project. They sell several lines of fabric paints and dyes. Dick Blick has silk/fabric paints and dyes. There are videos on YouTube for painting fabrics. Go to the manufacturer's home pages to check for compatibility with nylon and don't hesitate to ask for their suggestions. Be aware that many fabric paints require being setting with heat, like an iron.

As an alternative, consider going that retro route and using painted and/or dyed silk. It can be exquisitely beautiful. Waxed or oiled silk, lacquered papers, leather, feathers, and palm leaves have all been used by various cultures over time for their umbrellas.


How to draw duplicate items in perfect proportions and equidistant from each other in Mandala drawings?

You need to start with a sketch frame and fill it in from there. You're not going to be able to freehand draw it (without a ton of practice).

Start with a circle, decide how many radials you want (in your last example there are 16) and then sketch them in using a protractor to get them even.

I'd start with two perpendicular lines, then do the 45 degree lines (that makes 8) and then split those in half every 22.5 degrees... that gets you the 16. Keep splitting them further in half if you want the sections smaller.

So, with 16, you'll have something like this (you could probably actually just use this image and trace it or work on a light table):

From there, sketch in a ring everywhere you want a main point to be, say every inch (~2.5 cm). There's no need for them to be equally spaced, though. You can always start with a smaller design 4-6 inch diameter and then add to it later.

Here's an example:

Once you have the frame, fill in one of the wedges (or two/three if you want the full mirror effect).

Once the wedge is done, mirror it for the wedge next door. Use the rings to keep the placement. At this point, it's just the matter of filling everything in properly. If you do it correctly, you should have a perfect mandala at the end.

It's going to end up being similar to the process of duplicating a photograph or drawing using a grid pattern and filling in the grid rather than trying to draw it from scratch. Here's an example:


What is the best way to apply felt to wood?

Spray adhesive is a good match for this application. If you used the lower strength type, you might even have a decent chance of getting the felt back off later if you needed to for some reason.

Using spray allows you to get an even coat over the entire felt surface, avoiding lumps and/or hard-spots in the finished surface. The hard spots can arise where a glob or line of liquid glue is absorbed by the felt.

Spray adhesive generally has two modes of use, join surfaces while adhesive is wet, or apply to both sides and join surfaces after a drying period. I would go with the former in this case as the wet glue would allow you just a short period to work out any wrinkles. Also, it may reduce the holding strength, which will be much greater than needed anyway. That way if you ever need to remove the felt, you might be able to do it without shredding it.

Scotch-brand 77 is a common choice (pretty high strength though), and even mentions felt on the label: https://www.amazon.com/dp/B00114RCP0/


These are the ways I start over:

Walk away and leave the work out of sight for a few days.
Sketch out the scene on something that does not matter. Do that 10 or even 20
times. For example, I bought a roll of paper (40cm X 50 metres) for $5 and allow myself to waste this sketching out small compositions and tonal studies in charcoal (6x4") before I commit to working on a canvas. Sometimes I'll do 30 studies and eventually break through to a sense of flow and connect with the art again.

What causes this?

I have found freezing is also caused by a fear of commitment, that is, worrying about being unable to undo errors, being imperfect, or worrying about wasting materials like paper or paint. Sometimes it simply means I'm not sure what to do next. Being judged by others is a big one: I've stopped asking for feedback from family members.

Other solutions in a highly-regarded small book "Art and Fear"

I bought a copy of Art and Fear. Here's a quote from it:  “Fears about artmaking fall into two families: fears about yourself and fears about your reception by others.”

― David Bayles, Art and Fear: Observations on the Perils (and Rewards) of Artmaking

We will always have these fears!

Ask the art what it wants. Dialogue with your art

This is an approach derived from arts therapy (McNiff, S, Art as Medicine, Shambala Publications, Boston, 1992) (I recently completed a Grad. Dip. in this field). In its simplest form, settle yourself down, look at the work and gently invite the work to tell you what it wants.

Final note about art classes, and working on more than one work at once

Find a drawing class where the tutor can help, but to do that, speak to the tutor before you enrol and ask if they can help you. My experience is some tutors are very good at understanding how to manage our relationship with our art. One of current tutors has me working on three works at once, on small cheap canvasses. This has worked for me, and help me loosen up, and not get so attached to the one work.


Create a glass replica of something made of plastic (or other material)

Unless you are familiar with working with hot glass you would be better off seeking an glassworker to do this for you.

There are a few ways you could replicate the container: different kinds of casting or slumping (heating glass to soften it and letting gravity take over) but they are complicated, involve specialty tools and materials, and 1200°F-2000°F glass. Not something you could do on your own, unless you do glass working.

That being said there are plenty of glass artists around. Try to find a studio in your area. Art schools would also be a good place to find someone to do this for you. It would be an excellent exercise for a student in the glass dept.

A web search for "custom glass container manufacturing" has a few hits, but they are about making longer production runs like specialty bottles for a distiller. If money is no object you might convince them to do it.


What alternatives exist instead of freezer paper when it comes on shirt bleaching?

Freezer paper is a product that has a waxed coating on only one side. It's sort of like a hybrid of oven paper (also called parchment paper, baking paper, or ladokola) and wax paper.

Neither wax paper nor oven paper can substitute for freezer paper in this particular application, because the wax on one side is being used as a temporary adhesive. After heat is applied, the paper stencil stays in place firmly enough while the bleach solution is applied, but lightly enough that it can be peeled away when you're done.

So some possible alternatives -- which I admit I haven't tried, so they are all hypothetical:

Oven paper (or butcher paper) will work to keep the bleach solution, but will not have the same adhesive property and the stencil might move out of position while you work.
Use contact paper -- the video you link to doesn't recommend it because it will stick right away, not allowing for repositioning, but it would stay in place.
Use a spray adhesive to stick your oven paper down. (Make sure you look for one that's relatively weak, you don't want the paper on the shirt forever.)
Make a substitute for freezer paper per this online tutorial: a plastic bag ironed onto regular paper.
I wouldn't use wax paper with an iron because the wax would get on your iron, but maybe you could use a layer of wax paper under a layer of oven paper, protecting the iron but still letting the stencil stick!


How can a repair a hole in my sheepskin jacket?

I'd suggest you use leather glue to glue a patch from the inner side (with either leather or cloth - whatever suits the design of your jacket best). You can get creative with that and glue some logo or image instead of just a blunt patch (if so, you can do it on the outer side instead of the inner side). But from what I can visualise the leather is not only torn, but also stretched and deformed at the place. If that is the case, I'd suggest before you glue it to try to bring it back to its original shape as much as possible by dampening the affected place with cool water. Water will cause the stretched leather to shrink slightly once dry but while it is still damp you can also stretch it a bit if necessary. Do that only if you are sure water won't damage the jacket.


They actually make tools for this. They're called circle cutters. Some of them have the option to do a beveled opening. They're designed to make full circles or ovals but I'm sure you could use them for partial ones, too.

As an example this one has excellent reviews on Amazon and is made by the same company as your straight mat cutter but it looks like it may not be small enough as the minimum circle diameter is 4-3/4 inches and you said you wanted a 2 inch diameter circle.

Here's an example of a mat cut with this cutter:

Hopefully you'd be able to find a similar product with a smaller diameter.


I've "cheaped out" on occasion and just folded them in and up, sticking them into place with ordinary masking tape and ironing the pants at the fold afterwards. It's amazing how many washes the tape can go through before it needs to be replaced.


How can 'translucent' polymer clay become really translucent, if possible at all?

Based on this blog post about comparing the various brands of translucent polymer clay, it sounds like the translucent is only apparent when the clay is incredibly thin. The author prepares the clay by running it through a pasta machine.

  I compared every polymer clay brand’s translucent that I could find. I conditioned each clay, carefully avoiding the introduction of bubbles. I rolled sample sheets in the thickest setting (#1) on my Atlas pasta machine and the thinnest (#8) that I could make (the machine goes to a #9, but I’ve never had clay come through that alive). The thick setting is about 1/8″ (3mm) and the thinnest is about the thickness of a playing card.

The thick setting, when baked, makes the clay barely translucent in all brands, so if your figures are more than 1/8" (3mm) thick, you aren't going to notice the translucency at all.

As you can see in the image, you can just barely make out that there is text behind the clay... which is much more visible in the thin clay:


What type of thin or light wood is suitable for making box joints?

Plywood is ultimately the answer. When making box joints or finger joints you need to have dimensionally uniform and preferably stable wood.

Plywood comes in many sizes and I would imagine something like 8mm would be fine. If you are OK with something larger like 16mm then you would have stronger joints as there would be more surface area.

This is dependent on what tools you have. A box joint jig on a table saw would make this a breeze.

  I read here that pine wood is easy to shape and stain.

Pine is cheap. That is its main advantage. Most softwood is easy to shape by nature. Easy to stain is inaccurate as pine (and other woods) is susceptible to blotching. Blotching meaning a non-uniform stain.

Real wood will almost always certainly look better. On box joints you are going to see the plys more so you need to know if that is something you are comfortable with aesthetically.


How about a very thin acrylic sheet/plexiglass. It may not be as rigid as you need (being too thin), you have to check that for yourself. Also, plexiglass is not a very cheap material, generally speaking, but the price depends on the size and the thickness of the sheet, so what you are looking for may not end up being expensive. If that doesn't work for you, I'd suggest you go and look around a place where they sell construction materials and you will likely come up with a good solution.


How to make adjustments to a PVC raincoat?

I'd recommend you head to a camping supply store
 (like REI or Academy ) and pick up some tent repair tape.
 Its usually rip-stop nylon with adhesive on the back.
It will reinforce the pvc so you can add buttons etc.


Why are some acrylic yarns super soft and some not?

According to the "Acrylic fiber" page on Wikipedia: 'For a fiber to be called "acrylic" in the US, the polymer must contain at least 85% acrylonitrile monomer.' That leaves a free-for-all on the other up to 15% of fiber that goes into making up a yarn.

Although there are accepted standards for putting the weight and recommended hook and needle sizes on yarn, there isn't a standard for softness. Some companies do describe some of their yarns as being ultra soft or something similar, though.

You might be able to figure out how soft a yarn might be by reading what it's made of (if they were nice enough to list the fiber types in detail). The care instructions could also possibly tip you off. Another idea would be to visit chat rooms or crafting websites or reviews on shopping sites to get details about the yarn beyond what's on the label.

The disadvantage to relying on yarn companies or other people's opinions to tell you how soft a yarn is, though, is that softness is subjective. I may tell you that yarn X is incredibly soft, but you might not think so when you get your hands on it.

Probably your best bet would be to keep the name and other details of yarn(s) that you like the softness of and ask for comparisons between that and the yarn(s) you're thinking of getting. That way, if a person says it feels and/or behaves very much the same as your yarn, then you can be pretty sure you're getting something you'll like.


What materials can be lost wax cast easily?

It depends: What is your mold material ? I expect any type of glass  would fuse to any ceramic mold materials I am familiar with ( mostly alumina). And many glasses get soft and bendable at 1500 F , but that is nowhere  near liquid which will be 2200+ F.  How hot can you get your melting furnace? High alloy stainless ( 310 = 25 Cr : 20 Ni) melts "low" and has excellent fluidity. Vitalium is relatively unusual but common ( cobalt # 21 , Co + Cr) ; is used for silver colored dental applications and jet engine compressor blades. Maybe start with tin ( AKA pewter) very low melting ( roughly 600 F), good corrosion resistance.


Are there tell-tale signs that clay will crack when fired?

Yes. Look out for "veins" in the clay as it is altered and manipulated from its original resting state.

Veins might also look like threads or mini cracks.


It looks like a camel saddle. Numerous designs exist, for different camels & intended use (long riding trip, short ceremonial riding trip, pack animal, etc) and different regions. Some are made only for use as ottomans in houses, though! I remember the fashion for these was big in the 1970s. (I will never forget the one my piano teacher had near her grand piano in 1975, as she let me sit on it to wait, when my mom was late picking me up after my lesson)

One example: https://www.etsy.com/listing/603906532/old-camel-saddle-collectible-saddle


Mixing Acrylic Paint With Water ( And Storing It )

Paint is a chemical with a blend of several characteristics. Two of those characteristics are:
- Carrying a pigment (color)
- Sticking to a surface (glue)

A 50/50 mix would reduce the binder (glue) in the paint to half of what it was when it came out of the tube. If you were painting on paper or a medium that absorbed the paint you might get away with 50/50. Some paint makers recommend never thinning paint more than 25% with water (Liquitex thinning recommendation - not an endorsement).

  Think of the polymer molecules (the binder) as forming a sort of glue that holds the pigment onto the surface. When this glue, known as polymer, gets thinned by water, it loses its strength to bond. When the paint pigment is left unbound, over time it will release from the surface on which it was applied (usually canvas) and begin to flake off. "Don't user Water to Thin Your Acrylics"

Miniatures don't absorb paint so you are relying on the strength of the binder to hold the paint onto the miniature when dry. it would be best to "stick" to the paint maker's recommendation on using water to dilute paint.

I'm a little paranoid. When painting I use as little water as possible for spot thinning. When I need thinner paint for a large surface I use a painting medium to thin the paint. I don't want to do the work of painting only to have it mess up months or years down the road because I used too much water.

  Acrylic painting mediums can be used to thin acrylic paint in unlimited amounts "How to Thin Acrylic Paint"

You mention creating your own little pots like the ones the Citadel workshop uses.
Adding tap water to acrylic contains microbes and minerals - this can damage the paint. If you use water and plan to store the paint it's best to use distilled water. It's safest to use a painting medium.

The keys to storing paint are:
- Don't let it get contaminated
- Don't expose it to air.
- Use clean, air tight containers.

  Believe it or not, tap water is a contaminant. Tap water contains microbes and minerals. If you add tap water to a jar of acrylic paint and store it for a few years, it will probably develop mold.  from Does Acrylic Paint Go Bad?

The linked article above has good information on what makes paint go bad and how to store it.


How do I attach crystals to a shaman stick without using adhesive?

Adhesives based on pitch (e.g. resin from pine tree sap) and beeswax have been used for millenia.  This makes a hot-melting glue that's strong enough to secure knife handles.
One example is Cutler's Resin. Here's one of many recipes; other similar compounds include stone dust (e.g. ochre), and were used in ancient Eqypt (an old answer of mine).  The effect of the beeswax is to soften the pitch, while stone dust (or presumably wood dust) is used as a filler.
I reckon you might want to slightly inlay the crystals to make them more secure


Can I use hot glue as resin by melting them in a pan

It won't work.

You can melt hot glue in a pan, but it tends to turn yellow and eventually brown if it gets too hot. whether the mold survives the pouring depends on the material.

The real problem is that hot glue shrinks quite a lot while cooling down. The mold surface is cooler than the hot glue, so it sets at the outside first, while the center stays liquid for longer. As the center cools down and shrinks, it pulls all surface areas towards the center, warbing the object and possibly damaging the mold.

I've done this experience with a very small object: a papercut of a treasure chest, no more than 2 x 1 x 1 cm. I wanted to add weight to the object and filled the whole thing with hot glue. Once it was cool, the side walls were notably pulled in and there was a big (relatively speaking) hole at the top of the hot glue, where the top surface was pulled towards the center.


How to cut a small cylinder out of a chunk of foam with some precision

I would try to use one of the leather hole punchers in the right size. They come in different shapes, for your use I would look for the straight version. Like in this picture.
There is also a wider version, which can work well.
And if your hole is small enough and near enough the side of the foam, a pliers like tool (as in the picture on this page) may work. The page describes the other shapes as well.

And there is also something called a cork borer, which I have never seen in real life, which looks like it should work.

Those of the tools that do not have a base to them works best when you put a layer under your work, I learned that the end-grain of wood work well but a modern cutting mat may do as well, certainly when you only use hand power and not a hammer to push it through.


How does shading & blending with Carbon pencils differ from Graphite pencils?

I find that Carbon Pencils tend to dry out and break easily while I work. If I use carbon, I try buy one which is oil based; they tend to have strong tonal values without the shininess of graphite. You can make a very sharp line with a neatly sharpened pencil. I sometimes wet it with some linseed oil, or saliva, if it looks a bit dry.

Graphite is used as a lubricant in some industrial processes. So it applies more smoothly but I find the shine is annoying at times. You should consider the grade of your graphite as well. The ratio of graphite mixed with clay will affect the shininess in some pencil brands. The Staedtler Black Red 7B is an example that doesn't have a shiny gloss compared to other brands.


There are apparently several different methods for finding about what weight you're dealing with. All of these can have their own downsides but they're worth considering.
Note that, realistically, if you can't tell whether something is "sport" or "DK" but you know it's one of the two, it's probably not going to throw you off too badly.
Also note that the US and the UK have different terms for the same weights of yarn but that since stores sell yarn from around the world, you're likely to run into all of them regardless of where you live.
Wrapping
Wrapping is a method of testing the weight by seeing how many widths of yarn fit in an inch of space. It looks a bit like this:

You can wrap around the ruler itself or around something else like a pencil. The fewer widths of yarn that fit in an inch, the heavier the yarn is. Note that for thicker yarns, you might want to wrap more than an inch and divide to get a better count.
The downside of this is that not everyone wraps the same and yarn is squishy. They yarn in the image is very neatly wrapped but you could easily squash it together and get another 3-4 wraps in that inch.
Ply or strands
Generally heavier-weight yarns have more strands. This can be finicky with smaller weight yarns and it won't always give you the information you need because there's no real standard but if your yarn only has 2-3 strands, it's probably really light weight and if it's worsted it's probably 10 or 12 ply. So, if you use this in combination with wrapping (or some common sense) it will probably help you. There's a list of the ply to weight name chart on Ravelry.
By Gauge
You can determine whether an unknown ball of yarn will work for your project by making a gauge swatch. This requires that you are pretty comfortable with your stitching and are consistent but it should help. Use the recommended sized hook or needle for the project and follow the instructions for determining gauge for the project (if it includes those instructions) or use a base guide like the one here. If the stitch count per four inch swatch is really off, then it won't work. If it's good and it looks the way you expect, then go for it.
In this case, you should adjust for your own stitch style. If you know that you normally need to crochet with a 5.5 mm hook when the recommended size is 6.5, then crochet the sample with the 5.5 mm hook rather than the recommended one.
By Weight
Some people have really good scales. If you measure how long your yarn is and then weigh it (in grams) you should be able to find out the weight... because everyone wants to spend hours measuring the length of their yarn. The better your scale is (and heavier the weight), the shorter the length of yarn you can weigh.
I'd recommend that you weigh at least 10-20 grams worth of yarn and then figure out the length. Note that you don't have to cut the yarn to do this, just let the remainder hang off the scale and mark the measurement stop point with a small slip knot. It shouldn't affect the measurement too much.
Now that you have your weight to length measurement, you should be able to compare it to other known yarns and get an idea of what the "weight" group is. Though, note that the material your yarn is made of can affect its density so if you don't know what it's made of (which is likely since you don't have the label any more), you might want to try to figure that out, too.

As an aside, labels are annoying to hold on to plus the cat probably ran off with them or ate them... but I recommend that you avoid getting into this situation by logging your yarn purchases somewhere. Either keep track of your receipts (if they give identifying info about the yarn) or, even better, track your purchases on a site like Ravelry. This is great because it often has everything uploaded already, so you don't have to manually enter any of the data except (if you want) color name and dye lot. The section you're looking for is called "stash" under "my notebook".


Let's take a look at a photo of a colored object.
This is a simple, bright blue 20-sided die. I picked this because the shape and lighting make it easy to see multiple levels of brightness.

I then took this image and imported it into Adobe Color Wheel, which has quickly become one of my favorite tools for analyzing palettes when I don't have access to an art program. I find digital tools are a great supplement for learning traditional art skills, especially when you're teaching yourself.

Let's look at the immediate observations:

The hues all "line" up, which we should expect. It's a single-color object (excluding the text), and the lighting is clear and white, so there's no hue shifting
The tool captured the range of brightness levels, so we should be OK using this as an example

In this case, looking at the actually HSB number, we can see the shadow is actually slightly less saturated than the midtones, but the caveat here is that it's based on the pixel selected for that color. Picking different pixels from the "15" side in the shadow yield slight differences in saturation, and mainly it's on-par with the midtones.
But, as you've observed in artworks, the highlighted sides (17, 18), have decreased in saturation. Why is that?
Let's talk about light!
The way that light and objects interact is inverted from what we actually see. So a bright blue object like this, which is almost completely blue, actually reflects Blue light back to our eyes. The object itself is absorbing Red and Green light (when basing this on the RGB color scale, which is what visible light is based on).
When you shine white light onto an object, you're essentially shining all colors onto that object (the die, here). The shadows, receiving less light, will still absorb the Red and Green light, reflecting back lower amounts of Blue light. Because the amount of light is reduced, the brightness value on the HSB (Hue/Saturation/Brightness) scale with be lower, but the Hue and Saturation stay essentially the same.
But as you increase the amount, or intensity, of the white light being cast on the die, you reach a point where the physical properties of the object can't absorb as much Red and Green light, so it starts reflecting some of that, as well. When the light is strong enough, or a point reflective enough, it may even appear to us as pure white, which is a color with no saturation (like pure black or grey).
Since the light being reflected back is no longer pure Blue, the saturation decreases. This is because saturation (colorfulness, chroma, intensity, etc) is measured by the difference in the levels of color from gray, or in other words the difference in the dominant hue(s) from the remaining hue(s).
This also explains why shadows of a form still often maintain the same level of saturation: the die has no problem absorbing the meager amount of Red and Green being cast on it. Although, in this case, the object does absorb some Blue, so at low enough levels, we might see the saturation decrease, because proportion of reflected Blue light is lower.
Note that all this is mostly the theoretical application of light as it would apply to art. Rarely is a subject going to be lit from a single, clear, diffuse white light. Most environments are going to have multiple light sources, often not pure, and you'll be dealing with reflection of colored light off nearby objects. That's when the artistic eye and choices really come into play.


How I can calculate how much fabric I need to buy?

There are rule of thumb estimates for standard items of clothing.
If you go to a good fabrics shop the experienced staff may still know them. I do not expect to find them in the instructions for buying online.
They were rough estimates at best and mostly you would buy more than you would need.
The best way to work out what you need will be making the pattern pieces and placing them on a table as wide as your fabric. But remember that many pattern only give half the pieces and you use the fabric folded.