I am trying making a threadcutter to remove material for threads.
I have a nice spiral.
I have a profile curve.
The resultant sweep not only goes off the rail, but it twists, as well.
I tried adding more profiles, but that didn’t work either.
I might try making a high and lower spiral and try sweep2, but I am not optimistic.
No, Sweep2 did not do exactly what I wanted. I check the endpoints, to make sure everything starts where it’s supposed to.
I tried a single surface, but it twists that too. I think that what it needed was “Roadlike top,” but it doesn’t have that.
This is the result for a single surface.
I feel that if i put a whole bunch of intermediate curves in there–the result will have tension and twist where it’s not supposed to.
share your file if you want help
Without something akin to roadlike-top, there might be a reasonable solution.
While there is some powerful and sophisticated tools in Grasshopper, there are some missing basic functionality.
I encourage you to make some threads, using the missing spiral tool, and see how it works out with the missing road-like top.
Sweep2 seems to cut it ok:
helical thread demo.gh (29.8 KB)
Jeremy, will it work with root and crest?
Sorry, you’ll need to explain what you mean by root and crest - I’m not a thread expert
But here’s a version of the demo which is done with a proper metric thread profile (a 36x4 male thread):
I have added some notes to the grasshopper file:
helical thread demo v2.gh (40.9 KB)
But I’d stress that this is just a demo of how sweep2 can work OK in grasshopper for this. It isn’t a tool for generating threads (although it could be a starting point for one).
For ,the recors, here an old discussion on thread
Great resource, thanks Laurent.
I made a functional thread using the grasshopper tools with a 3d print in sand. There is a bit of friction but it works very well. As it is a bulb holder, it hasn’t to be opened and closed very often.