Some questions about pitch
tilllt opened this issue · comments
Hey, i was extremely relieved after finding your ThreadProfile Workbench, because for me as a beginner, the other options seemed to be way too complex. Unfortunally the accuracy of your tool is not really great i fear, probably because of using non-standard pitches.
The object i am trying to design is here:
https://forum.freecadweb.org/viewtopic.php?f=3&t=46254
So basically i just selected a M12x1 profile and changed the pitch to 0.5, since thats what a M12 board lens has. That doesnt work, the thread is too large after being 3d printed...
Is it generally possible to make a M12x0.5 thread or is my approach wrong?
Sorry to be so late replying. I just noticed your question today. You've probably already solved it or moved on in any case.
It could be the threads produced are inaccurate. I tested against some random ones I made with the Fasteners workbench and they seemed to check out okay, but there could be a bug or typo with some thread sizes for sure. Using a nonstandard pitch could also be problematic.
I think you did it the right way, select the M12x1 and change pitch to 0.5. If it's too big you could try adjusting the minor diameter down some amount. So, trial and error basically. Print a very short piece to try until your happy with the fit before printing the entire object. Another option is to print a plain cylinder and tap it afterwards. That's what I usually do. I haven't had much luck 3d printing small threads.