Patterning threaded holes may not work

[johnAMKDR]

There's an old forum thread: 

 https://forums.autodesk.com/t5/fusion-360-support/tapped-holes-don-t-pattern/td-p/8966969

which I had bookmarked because it showed a great example of Fusion's misleading terminology. I just had a similar problem and I re-read it. I'm wondering if this has been completely fixed or if it is still tricky.

I have 5 M4 tapped holes along a line. The first one was placed manually, and then a rectangular patter was used to place replicates. I did not have the thread modeling box checked and compute was set to Adjust. It looked like there were threads on all the holes, but when I checked the models on Xometry, I see the original hole has no threads but has a little extra detail (like a partial countersink) but the others appear to be just plain holes. If I check the Model threads box, Xometry shows threads, but also claims they bring DFM errors due to small radii.

When I export the file as iges or sat or step and open it, it looks like the Xometry version--plain holes for the replicates and a bit of countersink on the original hole but no threads.

I'll have to ask Xometry if the threads are really there, but from the AD side are the poor behaviors of patterned threaded holes fixed or are there recomendations for for correct working?

PS: please fix whatever is broken so that SAT files can be sent to the forum.

[g-andresen · Accepted solution]

Hi,

1. enable  thread option "Modeled" 

2. select  compute option "Identical"

tested STEP & IGES

günther

[TheCADWhisperer · Accepted solution]

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@johnAMKDR wrote:

PS: please fix whatever is broken so that SAT files can be sent to the forum.

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You can zip ACIS (*.sat) files to Attach to the forum.

But I would not use that file format as Autodesk products are limited to ACIS version 7 after a lawsuit of many years ago.  (Search Google on Autodesk Spatial ACIS wsgr.com)

ACIS is a proprietary format owned by Spatial while STEP (and IGES) are universal formats. 

[TheCADWhisperer]

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@johnAMKDR wrote:

replicates and a bit of countersink on the original hole but no threads.

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I would add lead-in Chamfer for the real threads.

I would not bottom tap holes (more expensive to manufacture due to tap breakage against chips in bottom of hole).  I would make the tap drill holes a bit deeper than tapped depth (at least 1.5 pitches).

Be careful how you do the lead in - most do it incorrectly.

And you can examine the geometry in Section Analysis.