Remove unnecessary history for mesh import for performance reasons?

[scott.sherin]

After a few attempts, my current process for importing STL files is to:

• Import mesh
• Convert the mesh to a body
• Cut the body pretty much randomly
• Combine the body back together

This leaves me with a body that has the faces you would expect, while remeshing would leave it with a lot of unnecessary faces. Potentially remeshing before converting to a body would improve the performance issues I'm having, but in this case I already have a bunch of history referencing the body that I don't want to lose by re-importing it. That being said, other suggestions for more performant mesh imports are welcome for the future. I thought maybe doing those steps as a base feature could help but I've noticed that import mesh is now only available outside of base features for some reason.

In this case I imported a gear with more than 10,000 faces, and ever since I've been having significant performance issues. Especially when interacting with the gear (e.g. creating a sketch on it takes ~10 minutes, extruding the bottom upwards to shorten it a bit took 15-20 minutes) but also just saving takes minutes now.

Basically I'm trying to remove the history of the mesh import/convert/cut/combine so it just leaves the final combined body without the import history in hopes it will fix this performance issue. I found the "Convert to DM feature" option in the timeline context menu and thought it might remove the history for that body up to that point or let me delete that history afterwards without affecting the now-DM body, but as shown in the attached images it absolutely butchers the timeline previous to the import for some reason.

Is "Convert to DM feature" the correct solution to this issue and I'm just encountering a bug? If not, is there some other way to do what I'm trying to do or to fix this performance issue? Thanks in advance.

[etfrench]

No reason to import spur gears, there's a built-in script for that.  If you still want to import an stl gear, then just import one tooth(and valley) and circular pattern it. 

Here's a screenshot of a 120 tooth timing belt pulley showing how it was modeled.

Involute gears are a little harder to model directly, but it's easy to convert a single tooth to a spline from a section of the stl.  The stl can be split in Fusion 360, Meshmixer, or Blender to get the tooth.

[scott.sherin]

Ya I found out about the gear generation add-in and I'm considering replacing my gears with those, but it doesn't solve the history problem unless I replace them far back in the history timeline and then fix all the problems that creates.

[etfrench · Accepted solution]

Without seeing your model, I'd hazard a guess and say it's probably best to start a new file.  You can save each of the components in your current file using the Save Copy As command.  Import those into the new file and position them with joints. 

It's surprising how little time it takes to remodel something after you have already done it once.

[TrippyLighting]

What makes you feel that the timeline feature is the performance culprit?

[scott.sherin]

I mean I can't be certain, but it seems like the mesh import is the culprit since that's when it started. And my theory is that removing the history of the mesh import could potentially fix it, since the body itself looks normal.

[TheCADWhisperer]

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@scott.sherin wrote:

In this case I imported a gear with more than 10,000 faces, ...

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STOP here.

Do not use this rubbish in your design other than for reference in creating proper geometry and then delete the rubbish.

[scott.sherin]

That's very helpful advice for my current situation. Obviously this wasn't the correct technique here since there are better ways to generate gears, but it's still sometimes necessary when trying to edit organic/artistic models when you only have an stl. For that I'll stick to my current process, but do it in a separate file so I can export the finished body to remove the history. It seems like they've implemented the Prismatic mesh conversion feature to basically do what I'm doing, but automatically. And worst case, sometimes I need to use meshmixer or 3D builder if the edit isn't too complex.

Currently I'm just trying to save the design by exporting the components without the gear, since trying to remove the gear or even just opening the align tool has frozen the application indefinitely.

[scott.sherin]

I think I may have to do that. Is it possible to export components as a group or so that they keep their relative positions?

[etfrench]

As long as they are all subcomponents with the same parent, you can use Save Copy As.  You can make them a rigid group before exporting.  If you have used Move and Align commands to position them, I'd recommend you use an As Built joint, then delete the move and align features from the timeline before exporting.

[scott.sherin]

I had a couple issues with this as I've never used a rigid group before. When creating the rigid group it didn't give me a joint type and then I still found no way to export them all at once, only right clicking a single component gave me the save copy option. I ended up using a Derive from the original file and then breaking links, which seems to have done the trick. I've lost my history and parameters, but I do seem to at least have my sketches (unconstrained and unparameterized) which is somewhat useful. Now that I know it works, I'm going to try it again without breaking links to see if it still fixes things but loses less information.

Thanks for the help!

Edit: noticed the parameters options at the bottom of the derive menu so I'm playing with those too.

Edit2: just in case anyone else needs this info, if you bring in the parameters with Derive, you can favorite them before breaking links and they'll stay in the new file.