Hi all,
I made a CAD file for a robot part, but whenever I go to print it, it turns out to be a mess because the outline doesn’t print correctly. The printer starts and stops extruding randomly, and the whole thing turns into a tangled mess pretty quickly. I know it’s a problem with the design and not the printer because everything else prints fine. Let me know if you have any advice, thanks!
There are a whole number of possible issues here that vary wildly depending on your CAD software, slicing software, model of printer, etc. Can you provide more information? If you could upload the STL somewhere we could see if anything about it looks off.
I use Kisslicer and Polyprinter. Here is a link to my file on grabcad: https://grabcad.com/library/rawr-1
Thank you
Do you have any pictures of what the attempted print looks like.
We stopped it after a few layers but here it is: https://imgur.com/gallery/DYwZnMB
It could be the case that the specific slicer software you’re using doesn’t like something about the model (in my experience, generally round parts). If possible, you might try using a different slicer or re-exporting the model to STL and slicing it again. Also, make sure your part is actually positioned flat on the “virtual” build platform in the slicer, since if it has a gap under it, the slicer may attempt to build supports for it, which could result in the odd behavior you’re noticing.
If your slicer allows it, see if you can view the resulting gcode in a single-layer graphical form, that way you can check each layer to see if the slicer is actually generating valid gcode, and if it is, then you have a problem somewhere in the printer (either firmware or hardware).
EDIT:
Looking at the model in a 3D view, it appears that part of the model extends down below the base, this would cause the entire model to shift upwards, and cause your printer to attempt to build it in mid-air, which generally results in the spaghetti-like print you posted above. Make sure the bottom of your model is completely flat and try again. 
I’ve attached an image pointing out the two pieces that appear to be below the rest of the model. Get these two pieces cleaned up, and I think you’ll have better luck printing it!
Hi all! I wanted to let everyone know that after I edited the CAD file, the robot part printed fine. Here is a picture if you were interested: https://imgur.com/gallery/7Ydli2d
Thanks!
