Modeling for 3D Printing

I was contacted by a forum member who will remain nameless. He has been trying to model a knob or something for 3D printing but he’s been having some difficulties. He was winding up with reversed faces as well as internal faces. Both of these will create problems for the slicer. His model is on the left, mine on the right.

His main problem stems from trying to layout all the details in 2D before going 3D. This seems to be a common issue. The trick is to start out thinking 3D from the beginning. I made a video to demonstrate how I would go about modeling this thing which you can see here. Notice that the only features I draw while my geometry is 2D is the circles for the through holes.

The only extension used with this model is Solid Inspector2 although it isn’t really necessary.

A few key points:

  • For circles, always drag out their radii on axis. If you drag out in some random direction you will create problems for yourself.
  • Before you get started modeling, set the units appropriately and turn off Length Snapping. The general wisdom from experienced SketchUp users is to turn off length snapping and leave it off. Best thing would be to make your own template that has that turned off already.

As always, a very clean approach! If the heights in the initial model are correct, these can be used as a reference for the push-pulls, then you need even fewer dimensions or inputs for the reconstruction.

Thank you. You’re right about using the original as a reference. I went through the process assuming the original wasn’t there. I only left it in the model space in the video as a reference and for comparison but I presume most people wouldn’t have that.