<p>I will be creating a small tube styled piece to use as a junction between two pieces of plastic. The idea is to reattach the two pieces and provide strength so they don't break apart again. I plan on using PLA.</p>
<p>My question is, will superglue (cyanoacrylate) work best for this or are there better choices for attaching PLA to hard (injected molded) plastic? The big thing I'm wanting to make sure is if any of these glues will dissolve the PLA and whether some glues might bond better than others.</p>

[{'answer_id': 6724, 'author': 'Himanshu', 'author_id': 12398, 'author_profile': 'https://3dprinting.stackexchange.com/users/12398', 'pm_score': 3, 'selected': False, 'text': '<p>Yes Super Glue is best choice.\nI personally use it in many PLA projects.\nI even apply Super Glue layer to ABS prints to avoid layer separation.</p>\n\n<p>It works well with both ABS and PLA, but exercise some caution whilst using Super Glue because it produces very bad tear gas. Use it in a well ventilated area.</p>\n'}, {'answer_id': 6725, 'author': 'Trish', 'author_id': 8884, 'author_profile': 'https://3dprinting.stackexchange.com/users/8884', 'pm_score': 6, 'selected': True, 'text': '<p>PLA is a nice one, and gluing has been a topic on some of our most favorite maker\'s channels. For example Stefan from CNC kitchen (<a href="https://www.youtube.com/watch?v=JSff8OMRHtw" rel="nofollow noreferrer">this video</a>) and Joel the 3DPrinting Nerd (<a href="https://www.youtube.com/watch?v=s1q2D_pK0BE" rel="nofollow noreferrer">this video</a>). Also, in 2022, <a href="https://youtu.be/dGE509zjf7E" rel="nofollow noreferrer">Tom\'s 3D</a> ran a test on glues for PLA, PETG and resin prints. Here some information from them together with my own experiences. Most of these glues are not exactly PLA specific by the way and work for many other materials too. Be careful with PLA containing infil though, as that can seriously alter the properties.</p>\n<h2>Step 0: Safety First!</h2>\n<p>Some of these methods are working with chemicals that can irritate the skin (resin, cyanoacrylate), have irritating fumes (acetone), or are flammable (acetone). Others (Cyanoacrylate) are not heat-stable and break down into their components under heat.</p>\n<h3>Use proper protection when working with glue! Eye protection and respiratory protection, as well as gloves, are to be used when necessary. Read the manual of the products you are working with!</h3>\n<h2>Preparations</h2>\n<p>For most glues, it is advisable to prepare the surface: sand it to increase the surface area, remove grease from fingerprints etc. Follow the manual!</p>\n<h2>Glues</h2>\n<ul>\n<li>Cyanoacrylate - yep, the &quot;one kind for all&quot; is a solution for PLA too: Superglue. However, look out for what type you get! Some are clearly better than others, and using an accelerator can change the properties of the glue spot.\n<ul>\n<li>Together with talcum powder, CA glue (&quot;superglue&quot;) can fill gaps easily. However, a gap-bridging bond isn\'t the strongest, and working can be finicky. Yet if the parts do sit flush, a CA glue bond can be a almost as strong as any 2-component glue bond tested, according to Tom.</li>\n<li><strong>CA is not stable under heating and when heated too much it breaks apart into a rather noxious fume!</strong> This can be handy to break metal-CA-metal bonds in machining of small parts but keep this in mind if you want to use inserts or plastic-soler pieces on the same areas! Don\'t tack with CA in those cases.</li>\n</ul>\n</li>\n<li>Epoxy resin - Epoxy is a favorite for very tough gluing, a few droplets can stick a car to the roof... and it warms up in curing. If you take a slow\ncuring resin, you can safely use it to glue PLA without the part deforming.\n<ul>\n<li><strong>Uncured Resin and their hardeners are strong skin irritants.</strong></li>\n</ul>\n</li>\n<li>2-Component Acrylic resin is just as good as epoxy often, as Tom noticed. It\'s very comparable to Epoxy in performance.</li>\n<li><a href="http://www.adhesives.org/adhesives-sealants/adhesives-sealants-overview/adhesive-technologies/chemically-curing/two-component-(2-c)/urethane-adhesives" rel="nofollow noreferrer">Urethanes</a> - 2 Component Urethanes offer strong but flexible bonds and work great according to Joel. Their curing process is also exothermic, so take care to not \'cook\' your piece.</li>\n<li>2-phase Putty - in a similar vein come 2-phase putties like <a href="https://www.games-workshop.com/en-FI/Green-Stuff" rel="nofollow noreferrer">Green Stuff</a> or <a href="https://www.milliput.com/" rel="nofollow noreferrer">Miliputt</a>, which harden after mixing. Their heat generation isn\'t too big and they allow to fill gaps easily. My favorite stuff though is not the expensive modeling putty but the stuff from the home depot: stuff like <a href="http://www.pattex.de/do-it-yourself-mit-pattex-klebstoffe-produkte-new/pattex-klebstoffe/reparaturkleber/repair-express.html" rel="nofollow noreferrer">Pattex Repair</a><sup>sorry, no English site for this</sup> or <a href="http://www.uhu.com/en/products/epoxy-adhesives-2-component/detail/uhu-repair-all-powerkitt-1.html?cHash=e0f929a3ec974e591e89c5e1987a30ab&amp;step=70" rel="nofollow noreferrer">UHU Repair All Powerkitt</a> harden within an hour, are surprisingly cheap and get a smooth surface.</li>\n<li>Acetone - We all know that you can smooth and glue ABS with Acetone or an acetone-ABS slurry. <a href="https://www.youtube.com/watch?v=VZUfq0yrtv4" rel="nofollow noreferrer">Tom (Thomas Sanladerer)</a> made a few experiments with it. He discovered that it works for at least <em>some</em> types of PLA in the following fashion: apply some acetone to a spot and press the second piece (that also was prepared this way) to it and they might melt themselves together after some time.\n<ul>\n<li>Effectivity of this depends <strong>very highly</strong> on the exact PLA you got.</li>\n<li><strong>Acetone is highly flammable.</strong></li>\n</ul>\n</li>\n<li>There\'s a type of glues commonly called &quot;Kraftkleber&quot; or &quot;Alleskleber&quot; in Germany, for example, <a href="http://www.uhu.com/en/products/special-adhesives/detail/uhu-hart-kunststoff-1.html?cHash=9e818145273de580c4e3c132faad3710&amp;step=202" rel="nofollow noreferrer">UHU Hart</a> or <a href="http://www.pattex.de/do-it-yourself-mit-pattex-klebstoffe-produkte-new/pattex-klebstoffe/kontaktkleber-gel-fuer-schwierige-oberflaechen/kraftkleber-transparent.html" rel="nofollow noreferrer">Pattex Kraftkleber</a><sup>German</sup>. While they often <em>stick</em> to PLA, I personally don\'t like their gluing power and find them often quite messy to work with. Also, they very much fail in loadbearing joints.</li>\n<li>Wood Glue - Yes, Wood Glue. PVA Wood glue as well as its non-water-soluble cousin (&quot;Express&quot;) have proven themselves to me as a rather nice surface coating to smooth over print lines as well as a good solution to affix paper and wood to prints. It is less of a solution for plastic-plastic bonds but works OK-ish.</li>\n</ul>\n<h2>Glue? Why glue?!</h2>\n<h3>&quot;Solder&quot;</h3>\n<p>What better way is there to combine parts than welding or soldering?! Often none. My personal all-time-favorite PLA <em>glue</em> is PLA itself, by using it as <strong>PLA solder</strong>. This method also works for most other filament types, but is not advisable for ABS and other plastics that emit fumes without wearing respiratory protection! In any case, you need to work with an exhaust, as you heat your plastic in a not always fully controllable way. If you can, use a soldering station where you can set the temperature of the iron.</p>\n<ul>\n<li>Take the pieces and make sure on both sides is a cavity that can be filled.</li>\n<li>Take a soldering iron and set it to around 200°C.</li>\n<li>Take a length of PLA filament.</li>\n<li>Melt the filament with the soldering iron and use it as solder when combining the two pieces. Make sure that at least some filament gets into the cavities and sticks there - it can help to stick the soldering iron into the goop in there to force it to merge with the infill/walls and press together to hot PLA goop filled pieces against the iron before pulling it away, pressing the pieces together.</li>\n<li>As the PLA cools and hardens, the joint is usually tougher than the actual layer boundaries.</li>\n</ul>\n<h3>Pen</h3>\n<p>Instead of using a soldering iron, one might also use a 3D printing pen<sup>One that eats filament, not one for PCL or some gel!</sup>, but I don\'t like those personally.</p>\n<h3>Inserts!</h3>\n<p>On a different note, a soldering iron is also a very good solution to make inserts into PLA - heat up the metal insert (like a nut) and press it into an undersized hole, and it will mold the plastic around itself into a perfect fit without any glue.</p>\n<h3>Friction Welding</h3>\n<p>An alternative to using direct heat from a soldering iron is <strong>friction welding</strong>. For this, take a rotary power tool and some filament. Insert the filament into the tool, tighten and cut so that about an inch is reaching out of the claw. Turn it on at medium speed, about 800 to 1200 RPM. Now, once you press the tip of the spinning filament against other PLA it gets hot and melts, creating a welding seam. <a href="https://www.youtube.com/watch?v=Pa2DoE3sirU" rel="nofollow noreferrer">Joel</a> has a good explanation.</p>\n'}, {'answer_id': 14476, 'author': 'Kristin', 'author_id': 23685, 'author_profile': 'https://3dprinting.stackexchange.com/users/23685', 'pm_score': 2, 'selected': False, 'text': '<p>I used to work at a small thermoforming plastics enclosure company and we used “weld-on” for basically ANYTHING. Delrin and medical grade plastics not included but, PC, PE, acrylic, PETG, etc. use &quot;weld-on number 3&quot; for more easy bond plastic, &quot;number 4&quot; for more crystalline/harder to bond plastics.</p>\n'}, {'answer_id': 14485, 'author': 'amra', 'author_id': 75, 'author_profile': 'https://3dprinting.stackexchange.com/users/75', 'pm_score': 1, 'selected': False, 'text': '<p><a href="https://www.3dgloop.com/shop/pla-gloop" rel="nofollow noreferrer">PLA Gloop</a> is dedicated glue for PLA. It contains chloroform, so be careful.</p>\n<ul>\n<li><a href="https://www.youtube.com/watch?v=gTtW_NXFMCY" rel="nofollow noreferrer">3D Gloop! // 3D Printing Adhesive Spotlight</a></li>\n<li><a href="https://www.youtube.com/watch?v=vQc5TBPF8uw" rel="nofollow noreferrer">PLA Smoothing 3D Prints with 3D Gloop!</a></li>\n</ul>\n<p>Additionally a PrusaPrinters guide: <a href="https://blog.prusaprinters.org/the-great-guide-to-gluing-and-assembling-3d-prints_44908/" rel="nofollow noreferrer">The Great Guide to Gluing and Assembling 3D Prints</a></p>\n'}]
['https://3dprinting.stackexchange.com/questions/6723', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/11242/']