Trying to add 1/4-20 threads to this part

[Anonymous]

I am having an issue when trying to print this part because the threads are not perfect on the inside of the piece.

If I remove the threads the hole looks perfect, but when I add them it has some issues on the inside.

I had to change the offset to get the threads to look correct from the outside, but on the inside you can see the part has some issues.

How do I correct this?

Thank you

[Anonymous]

Here is the front of the part

[jeff_strater]

I think this is a bug in Fusion with "modeled" threads.  I suspect that it is because the hole is in a cylindrical face.  My guess is that we don't extend the threads quite far enough to get all of the geometry at the cylinder boundary.  We will look into that.  Thanks for reporting it!

A workaround (not a particularly great one, I realize) is to do this the other way around - instead of a hole, model a threaded cylinder, and subtract it from the cylinder using Combine.

For instance, in this image, the red body is a separate body, with "outside" threads applied to it.  Position it as you need to:

Then, use Combine, select the green body as the target, and the red as the tool:

And you should get better results:

Hope you can get past this problem.

Jeff Strater (Fusion development)

[Anonymous]

Ok that is very interesting, I will try it like you said and see if that works.

Thank you