topic Re: Coarsest Thread Available? (3D Printed part reverse engineering) in Fusion Design, Validate & Document Forum

Coarsest Thread Available? (3D Printed part reverse engineering)

thoreaubakker — Wed, 22 Sep 2021 17:36:52 GMT

I'm trying to recreate a coarse thread with the following characteristics:

Roughly:

minor diameter 30mm

major diameter 37mm

pitch 6mm

When clicking on the 'create thread option', it defaults to a M32x2 with a much shallower (steeper?) pitch, meaning I have way more threads than I'd like. The part I'm helping reverse engineer is a 3d printed part with low tolerances, and can be tightened with 4 or 5 turns of the hand as opposed to 20 etc with a finer thread.

What is the coarsest thread available in the create thread tool?
Do I have any easier options than the custom thread profile creation (heard something about xml files or something in someone's earlier post).

Attached images of the part I'm trying to reverse engineer vs the too many threads I'm getting with the create thread tool.

Re: Coarsest Thread Available? (3D Printed part reverse engineering)

HughesTooling — Wed, 22 Sep 2021 17:47:35 GMT

Have you tried using the coil feature? You'll need to experiment the section size and diameters a bit but might do what you want. Just create it around a cylinder.

Re: Coarsest Thread Available? (3D Printed part reverse engineering)

HughesTooling — Wed, 22 Sep 2021 17:56:16 GMT

If you try this, see attached file for some pointers and an idea for the run out at the end of the thread.

I created a sketch with a line 5mm from the intersection between the thread and the cylinder to use in a rotate feature.

Re: Coarsest Thread Available? (3D Printed part reverse engineering)

HughesTooling — Wed, 22 Sep 2021 18:04:51 GMT

Adding the fillet reduces to OD a bit so I came up with this sketch so you can get a reference and adjust the coil to suit.

Re: Coarsest Thread Available? (3D Printed part reverse engineering)

thoreaubakker — Wed, 22 Sep 2021 18:32:02 GMT

Wow, @HughesTooling thanks for quick reply and generous exploration / hard work.
Since this post I've been watching videos and it seems like you're spot on.

One question I have: do you have any suggestions on modeling the female side of these threads?
Should I just Boolean a cavity out of a black and offset faces? That's one thing I'm a little confused about.
Thanks again - BIG TIME!!!

Re: Coarsest Thread Available? (3D Printed part reverse engineering)

HughesTooling — Wed, 22 Sep 2021 18:40:47 GMT

@thoreaubakker wrote:

One question I have: do you have any suggestions on modeling the female side of these threads?
Should I just Boolean a cavity out of a black and offset faces? That's one thing I'm a little confused about.
Thanks again - BIG TIME!!!

You are going to need some clearance so I'd say use a slightly bigger coil to cut the female form. You probably don't need to worry about rotational alignment in your models so don't get hung up on that.

Mark

Re: Coarsest Thread Available? (3D Printed part reverse engineering)

thoreaubakker — Wed, 22 Sep 2021 19:10:31 GMT

Thanks again.

I really appreciate the reply Mark.
Will be experimenting the rest of the afternoon.