Screw Thread Exact Profile



I’ve been following that great tutorial about making screw thread and I was able to make screws:

I need now to build a screw that has the profile reference of UNC 6-32 but I am not succeeding…

I found the BoltGen plugin which makes screws for you and it sounds like a dream:

Followed the steps to install the plugin on mac and even tried to put the file manually. But Rhino tells me the file isn’t compatible.

If I am correct, does it mean that a .rhp file isn’t a cross platform file like I thought but some could be only read from Windows and not Mac?

If this is the case. I would very much appreciate help to how to make a precise profile of screw and/or is there a screw generator that works for Rhino Mac?

Thanks a lot.

(John Brock) #2

You’ll probably have to pull out your copy of the Machinist’s Handbook (or Google search), to get a dimensioned sketch of your specific thread profile. Draw it in Rhino and sweep it as you have in the tutorial.


Maybe not what you’re looking for, but you’ll find a lot of stuff already drawn here;

I download step files and import directly.



Thanks! Making the screw was just to difficult…

I did find a STEP file of my screw and could import it into Rhino. All good now!


Great, glad I could help. Just a word of warning, I haven’t actually checked if the screw threads are exact or if they’re just a modelisation. If you see what I mean…


I’m the creator for BoltGen, and also am having difficulty getting a Windows python .rhp program to work in Mac. There seems to be a lot of problems porting to Mac. However, I do have a working copy of BoltGen and would be pleased to create what you need and send it to you. Email is:

Regards, Ray McKaig