CAD of Actual 3D Printed Parts - Mass/Center of Mass/MOI

Something came up when thinking about 3D prints in the robots and figuring out mass and center of gravity. You make the CAD, then print it, and now you have your part. Super cool - BUT - now this part does not represent what is in CAD from a mass standpoint. Wall thickness, infill %, etc. isn’t represented in CAD at all.

How does everyone take this into account in their CAD models? Any cool tricks?

We just set it to the density of nylon, it’s close enough that it doesn’t really matter, and it’s also an overestimate. Most of the weight comes from metal and motors anyway, so estimating the mass of 3dp parts isn’t a big concern.

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Julia’s featurescript has a “3D Printed Mass” featurescript that actually allows you to set material, infill density, wall thickness and # of walls for different parts.
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However, this solution is only applicable if you use Onshape,

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That makes sense, certainly true for FRC. For FTC we use lots of printed parts. Thank you!!

We do use Onshape :slight_smile: So thank you!!! This is great!

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Depending on your slicer I believe you can export your toolpaths as an OBJ file and then re import that back into your cad package of choice. If you really want to account for infill etc.

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