topic Re: Custom 29MM Thread Size in Fusion Design, Validate & Document Forum

Custom 29MM Thread Size

narey3AVQN — Wed, 24 Jun 2026 09:47:22 GMT

Hi guys,

I've commissioned a project, and one of the fittings needs a 29MM thread - the engineer uses Fusion360 and said that he does not have a 29MM thread size available and that it would need to be made, then imported into his software to use it.

The above picture is what he needs to select to complete the project, does anyone know if anyone sells thread profiles for what I need, or if I can commission anyone to make the above spec?

Thanks!

Re: Custom 29MM Thread Size

HughesTooling — Wed, 24 Jun 2026 14:23:17 GMT

Take a look through this thread where there's a utility to help create custom thread XML files for Fusion.

Re: Custom 29MM Thread Size

narey3AVQN — Wed, 24 Jun 2026 14:32:28 GMT

Thanks for linking this.

I've already sent him this previously, but he isn't willing to spend the extra time to make it, or alter an existing CSV to fit - so I'm hoping I can commission someone to do it on his behalf just to get this project finally over the line 😕

Thanks,

Re: Custom 29MM Thread Size

andrew2085 — Wed, 24 Jun 2026 14:54:03 GMT

These values are 1mm smaller than the M30x3.5 6g spec used by Fusion:

<ThreadSize> <Size>29.0</Size> <Designation> <ThreadDesignation>M29x3.5</ThreadDesignation> <CTD>M29x3.5</CTD> <Pitch>3.5</Pitch> <Thread> <Gender>external</Gender> <Class>6g</Class> <MajorDia>28.7345</MajorDia> <PitchDia>26.568</PitchDia> <MinorDia>24.732</MinorDia> </Thread> </Designation> </ThreadSize>

Re: Custom 29MM Thread Size

Warmingup1953 — Wed, 24 Jun 2026 16:18:45 GMT

Using Andrew2085's code, I asked Autodesk Assistant to help. "It" added the spec in the right location then prompted a restart as the Cache would not clear, and then I simply used the Thread command that now has M29 added.

WARNING: I have not tested

Re: Custom 29MM Thread Size

Drewpan — Wed, 24 Jun 2026 23:45:32 GMT

Hi,

What is the actual requirement for this custom thread? Under normal circumstances

a Designer would simply go to the next standard thread size, 30mm in this case. A 1mm

increase in thread size shouldn't cause significant issues unless there are incredibly

tight clearances. Has the Engineer actually calculated the physics of using such a

specific thread size and come up with this for actual clamping and vibration reasons?

How many of these custom size fasteners are required? If you need a handful then it

will be much cheaper to simply use an alternate. If you need Hundreds or Thousands

it will be significantly cheaper to redesign for a larger size.

The fact that you "can" make custom thread sizes in fusion doesn't mean you "should"

do so. Standards exist for a reason. Sure a 29mm fastener is a significant size but it

will still involve custom fabrication and that costs money and time. The other problem

you may run into is - do you also need a custom tool to use it? There will be no 29mm

spanners or sockets and it may not be suitable for some kind of adjustable tool. What

about future maintenance in the field? A custom size fastener could cause all sorts of

issues, especially in a remote location.

I am asking these questions for my own curiosity but also because any engineer should

be asking these questions when creating designs.

Cheers

Andrew

Re: Custom 29MM Thread Size

pkomatlapalli — Tue, 30 Jun 2026 14:37:20 GMT

Hi @narey3AVQN ,

Good day!

We would like to check back on this issue. You have received responses for your post from these community members andrew2085 and Warmingup1953. Does any of these responses helped resolved your issue.

If yes, please click on the "Accepted Solution" button, It would be very helpful for others who may encounter the same issue in the future.

Thank you!