I really don’t understand why people only upload .stl meshes of models. I’m trying to create and accessory for my Dremel, and I thought I find other models with the correct threads that I could use to boolean the threads in my design. There are lots, including just a threaded piece for boolean, but it too is .stl. Is there some way to boolean a .stl mesh from a nurbs block?
In some situations you can turn each triangle mesh face into a surface and join into a closed polysurface.
When you say accessory for a Dremel… are you going to to 3D print it?
Probably.
Then why not forget about nurbs and subtract a mesh from a mesh?
I only know how to model in nurbs with Rhino. I realize I can model in nurbs, save as .stl and then add the threads by mesh boolean. I guess I just have bias against using faceted triangles to make curved objects. I’ll need to get over it.
you will likely need to run a tap thru the threads after printing anyways, so they just need to be accurate-ish.
grab a bolt with the correct thread from mcmaster carr and mesh it with decent density, then do a mesh Boolean subtract to get your threads, print, tap and you are good to go.
I do this all the time it works great.
In addition to the great McMaster method - (use that here on the regular) … there’s also a great plug-in on the PackageManager - BoltGen
… have been using it for a while, and only just recently realized in addition to the standard nuts and bolts it can also generate a “cutter” solid, which is slightly offset-ed appropriately to where in some cases no post-operations are needed
Yeah. McMaster-Carr is always my first stop, then GrabCAD. But neither had the m19-2 thread. (nor did FastenWorks) I did find this model, which is again .stl. https://www.printables.com/model/35010-m19-2-rotary-tool-thread
I’ll try it doing what I proposed above.
use mesh booleans and plan on cleaning the threads with a tap and you will likely be good to go with little to no effort.
other option is to try the new fastenworks plugin from packagemanager… I’m messing with it atm..it’s pretty good.
For you perhaps,
that’s a shape I don’t know how to create. I would probably approach it sweeping the thread angle along a spiral, but I don’t know how I’d get a no- faceted spiral from the mesh?
This mesh is so clean that you can get a section of the thread and then simply draw a new helix from one tooth to the next and then sweep
As I mentioned, I could not find 19-2 threads in Fastenworks or any of my usual sources. It seems it is an odd size. I could be missing something.
The thread angle also looks a bit unusual, chances are it is actually wrong in that *.stl above
Draw a new helix with which tool?
_Helix 
Check out this vid :
Following this guide was instructional in helping me to create this optical component fixture - which has unobtanium threading. An SLA print worked without post-processing.
THREAD EXAMPLE.3dm (13.3 MB)
