How to calculate size to match standard fittings with prints?

Hello, this is my first post
I have been trying to figure out how to accurately measure the size of a thing and sculpt slice and print a complimentary object.

For example, How do i match threads if I want to sculpt an attachment for something?
Or if I wanted to make a clip for something to hold it, that is functional and fits the object with little error?

IDK if there re standards that people build on top of, or if they end up matching screw threads perfectly, but I am trying to acquire that skill.
Thanks in advance for any help!

This is something people typically do with a 3D CAD program like FreeCAD or Fusion360 (or even something like Blender). There are lots of tutorials for that. For example:

Those programs tend to have features or add-ons to make typical physical design tasks like this easier. By contrast, Nomad Sculpt is more oriented toward 3D sculpting where the appearance is the primary concern.

There likely is a way to do it with Nomad Sculpt and, someone else might have suggestions on how. It is worth considering learning one of these other tools, if you are going to be doing a lot of that kind of thing.

If you can find an existing model of your existing physical component, you might be able to create a mate by using a subtractive Boolean operation to cut it out of a solid object. Places like Digikey have downloadable models of a lot of components they sell and, you might be able to find something with the diameter and thread pitch you need to match.

As Evermorian mentioned, this is something that you should probably be doing in a CAD software.

That being said, there are ways of doing it but it can be very cumbersome. You can do a search on the forum of “thread” and should be able to find a few posts where people create them and show how to.

One thing I’ve done quite often is create my threads in a separate software and import them into nomad. Then merge then into parts I’ve designed in Nomad. Works very well and makes it so I know my threads will work :+1:t3:

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Using a sculpting program in hopes of doing technical modeling is nothing short of pure masochism. Sculpting’s criteria is “If it looks good to the eye, job’s done.” CAD is object modeling (almost always) based on or driven by data.

This would be true even of ZBrush’s ZModeler component. You only approximate where a hole is placed.

In CAD, a hole is often placed either in relation to a known feature (centerline, edge, etc) or placed outright by a value (ie, 3.55mm from origin with 4.25mm radius). Wake me up when you find seasoned sculptors who wish to “sculpt” this way.

As @Evermorian pointed to in the FreeCAD tutorial, I used a similar process in Rhino3D starting with a helical coil where I’m allowed to specify diameter, height, number of turns, etc. Another curve is designated to sweep along the coil creating a precise thread. The screw threads are used to (Boolean) cut out its negative shape in other CAD-modeled structures giving me custom-made 3D printed valve stem caps:

For a first-try, they twisted on with the same ease as a manufactured valve stem cap. No cross-threading, no tightness, no looseness.

For more common fasteners, there’s even a free plug-in made available to Rhino3D CAD users that generated industry-standard bolts.

Given this demonstration of CAD’s precision, there isn’t much reason why Sculpting apps need to reinvent the wheel here.

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