<p>I've created a little enclosure for a project in sketchup
<a href="https://i.stack.imgur.com/m8AB9.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/m8AB9.png" alt="enter image description here" /></a></p>
<p>I then exported the .STL</p>
<p>When I open it in Creality slicer 4.8 or Cura 5.0 It looks like this
<a href="https://i.stack.imgur.com/uD4eb.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/uD4eb.png" alt="enter image description here" /></a></p>
<p>I thought that the red was &quot;overhang that needs support&quot; (but can also mean a shell?)</p>
<p>Hoever, that's not the irritating part. That would be the grey in the middle where the &quot;hole&quot; should be.</p>
<p>When I slice it, it looks like this:
<a href="https://i.stack.imgur.com/ew0yy.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ew0yy.png" alt="enter image description here" /></a></p>
<p>I didn't notice this before I started printing and 4 hours into the print I noticed that it was just completely ignoring the window and was considering it as a part of the base.</p>
<p>Why is it doing this and how can I fix it?</p>
<p>I've tried editing the original sketchup model a number of times, but I keep getting the same result.</p>
<p>I read the question and answer at <a href="https://3dprinting.stackexchange.com/questions/5068/empty-space-in-model-is-getting-filled">Empty space in model is getting filled</a> but I'm not 100% sure that this is the solution I'm looking for.</p>
<p>The slicer, knows enough to see that the hole should be there, as it is rendering in a shaded area. It feels like there is a setting or some such that is &quot;print the shaded area&quot; with a checkbox (on or off) - and if that setting is there, someone please tell me where to find it!</p>
<p>I've also tried importing the STL into other programs (like fusion 360) and RE-exporting the STL, but the issue persists.</p>
<hr />
<p><em>Please note that  <a href="https://3dprinting.stackexchange.com/questions/13352/sketchup-designed-block-with-hole-printed-solid-in-cura">this question</a> seems to be similar to mine, however, there isn't an accepted answer. The one provided below is actually a much better answer.</em></p>

[{'answer_id': 19669, 'author': 'court3nay', 'author_id': 11248, 'author_profile': 'https://3dprinting.stackexchange.com/users/11248', 'pm_score': 0, 'selected': False, 'text': '<p>In Cura, you can indeed set the height of the first layer separate from the subsequent layers. So if the first layer is printing nicely, that\'s a good sign. That\'s usually the place prints fail. There are a few settings, but here are a few things to just double check:</p>\n<ul>\n<li>Is your nozzle set to the right size</li>\n<li>Is your raft layer height and regular layer height wildly different? Try setting them to the same, or if same, try making them different. There may be a \'raft top thickness\' that\'s wrong for the nozzle size, (try 0.2 for a 0.4\xa0mm nozzle)</li>\n<li>Layer height of your regular layers should be no greater than 80% of the nozzle width</li>\n<li>Print cooling (on), but initial fan speed (0)</li>\n<li>Supports: try printing with, or without. Look at Enable Support Interface (or disable it)</li>\n<li>Try just disabling your raft and see if it gets past the danger point. that will indicate if there\'s something misaligned with your Z.</li>\n<li>Check your axis rollers too! from this question, <a href="https://3dprinting.stackexchange.com/q/8022/4762">First 3 mm prints poorly, then fine after that</a></li>\n</ul>\n'}, {'answer_id': 19675, 'author': '0scar', 'author_id': 5740, 'author_profile': 'https://3dprinting.stackexchange.com/users/5740', 'pm_score': 1, 'selected': False, 'text': "<p>PLA doesn't need a raft.</p>\n<p>Try printing without a raft. If you print with a raft because of adhesion problems, solve those first. A raft is only needed for filaments that shrink a lot and/or are printing at very high temperatures.</p>\n<p>If you want a raft, check the distance between raft and print object and know that a raft never gives a smooth bottom. This is because in order to prevent fusion of the print object to the raft a distance between the raft and the print object is accounted for. A property that controls the distance between the raft and the print object is called <code>Raft Air Gap</code> in Ultimaker Cura. Default for my setup this is 0.3\xa0mm which I find rather large.</p>\n<p>For example (not raft, but support with a solid top layer, which is quite similar to a raft), I have used support structures with a roof to support large flat overhanging areas that where printed at 0.2\xa0mm distance, this gave relatively good surface quality and barely no fusion to the print.</p>\n"}, {'answer_id': 19677, 'author': 'LUCAS P.', 'author_id': 34806, 'author_profile': 'https://3dprinting.stackexchange.com/users/34806', 'pm_score': 1, 'selected': False, 'text': '<p>It seems to me that the problem is over extrusion. Those temperatures might be a little high for this PLA. In my settings I usually put it on 200 or 205\xa0°C (when printing faster). But the real problem might be a wrong extrusion multiplier for the first layers or a mixed with temperature, low speed, or no retraction.</p>\n<p>My advice:</p>\n<ol>\n<li>Try a little bit lower temperature</li>\n<li>Try reducing the first layers extrusion multiplier</li>\n<li>Try increasing the retraction a little bit</li>\n</ol>\n<p>For the problem of not extruding plastic at the beginning, you should print a purge line (as Ender 3 does) or print a skirt (instead of a raft, that you might not need). This problem is very normal and is easily fixed.</p>\n<p>The bed temperature is correct for PLA (60\xa0°C).\nMaybe, only maybe, your nozzle is a little bit high. It should squash the plastic on over extrusion, which I think is not happening in your setup. My advice for this is to use a paper sheet and fold it once.</p>\n'}, {'answer_id': 19693, 'author': 'rohtua', 'author_id': 34784, 'author_profile': 'https://3dprinting.stackexchange.com/users/34784', 'pm_score': 1, 'selected': True, 'text': "<p>Hi Thanks for all the suggestions. I've been experimenting with various prints using some of the different settings and it appears that I needed to increase the initial layer height. Now the first layers are printing as they should.</p>\n"}]
['https://3dprinting.stackexchange.com/questions/19671', 'https://3dprinting.stackexchange.com', 'https://3dprinting.stackexchange.com/users/34792/']