Simple bottle thread by boolean difference

Hi there, I am having an unusual problem (I do this all the time but cant figure out this problem) with this boolean difference for a bottle thread/screw. I created the negative screw with helix + sweep1 commands as usual
bottle thread.3dm (761.6 KB)
but apparently the created surface cant complete this boolean difference. It is a closed polysurface so i dont know.

Hello- the problem is the thread object is, itself, self-intersecting.


Can you post a file with the helix and section curves used to make the thread?


Oh okey. Here is the file.
I moved the helix curve and the screw faces to the side. They are 20mm upper from the other part that needs the boolean difference.

Thank you!!

graffo.3dm (7.6 MB)

Hi Francisco - I would carefully construct one revolution of the thread, copy it as many times as needed then, if you like make a solid ‘plug’ from it to use as a cutter; if you want the threads to taper out at the ends, it does get a bit more complicated but the basic structure should be something like this -

Thread.3dm (1.2 MB)