After 3D scanning an object or buying a model from turbosquid/etc, a lot of our clients need to change their 3D sculpture digitally. You can do it yourself, for free!

If you don’t have a 3D model yet, here’s how to get one.

Types of 3D Part

There are pretty much 2 types: surface based and math based.

Surface Based models are artful, naturally imperfect (a flower, a cookie, an animal) and 2/3 of what we make. The important thing with surface models are the looks, so they’re common for art. It IS possible to add specific dimensions and dowel holes and all that to a surface based model, but the majority of the model is free-hand sculpted. There are a ton of free editing programs, and a few major filetypes that they all use:


Math Based models have perfectly flat/round/spherical surfaces. Exact dimensions are important on these models, as well as symmetry, parallel surfaces, that sort of thing.  This type of model is used for manufacturing (a cell phone case, a door for your house, a piston in your engine). Most editing programs are paid, some are free – here are some examples:


Modifying Surface Based Models

I vote for Meshmixer for quick sculpting, slicing, etc. Here’s a great video on the meshmixer basics:

If you’re sending your project to us, we’ll take care of the scaling, file size, and slicing it up (unless you want to do it yourself). As long as the entire part looks like what you want in the end, we can do the intermediate steps quicker on our end.

I typically use the sculpting brushes Draw and Robust Smooth to get a huge chunk done, and the combine/difference operation to do things like cutting a round hole all the way through a part, or make a negative mold.

Here’s a series by Autodesk on each of the basic tools available:

Modifying Math Based models