LibLathe - Lathe Path Generation

[JoshM]

[
Isn't the axis of rotation always around the Z axis?

The horizontal Z-axis on the lathe strikes me as a local coordinate system that job models are translated to align. What is different about this compared to machining jobs that require aligning the model to face toward +Z?

[sliptonic]

[
Isn't the axis of rotation always around the Z axis?

The horizontal Z-axis on the lathe strikes me as a local coordinate system that job models are translated to align. What is different about this compared to machining jobs that require aligning the model to face toward +Z?

conceptually there's nothing different. Almost all the milling operations assume Z+ is 'up' and that the spindle is aligned with it. The question that was posed here was about knowing the axis of rotation. I'm suggesting we can Assume it is around the Z axis and expect the user to align the model correctly. In other words it would be silly to have a property of a lathe job being 'axis of rotation' and the user selecting it.

Practically, the difference is that getting a model correctly aligned seems to be a real challenge sometimes. Try it and tell me if I'm wrong. The job setup tools need improvement to handle lathe orientations more smoothly

[JoshM]

I agree. In concept, I would assume that any model would require alignment so it is aligned—and centered on—the z axis, in the job setup. As you mentioned, with user option to reverse between +/- z.

Broadly, most job models milled in Path are generated in FC, so in many cases, this isn’t an issue.

Agree that alignment of a general step model at an arbitrary translation sounds more complicated.

One thought—if the model at its existing translation is rotated around the z axis, it moves through minimal XY space when aligned.

Another thought—real lathes have a limited available cylindrical volume that the stock/model must be centered in. Doesn’t the assembly workbench provide this functionality?

[dubstar-04]

Hi All,

I have made a PR https://github.com/FreeCAD/FreeCAD/pull/3951 to add some base features required for the turning functionality,

Once these changes are landed the turning operations should be available via this addon: https://github.com/dubstar-04/FreeCAD_Turning_Addon

With the addon installed the operations should be available via the Path Menu:

turning addon.png (32.75 KiB) Viewed 1429 times

Note: The Turning functionality is nothing more than a proof of concept. The intention of releasing it as an addon is to encourage collaboration and testing to encourage development.

[Kunda1]

I could also add it to the Addon manager

[dubstar-04]

I could also add it to the Addon manager

That would be great! Does the addon manager resolve submodules?

[Kunda1]

That would be great! Does the addon manager resolve submodules?

I'd need to check. I'm thinking it doesn't but not certain.

[dubstar-04]

That would be great! Does the addon manager resolve submodules?

I'd need to check. I'm thinking it doesn't but not certain.

Ok great. If not I could split LibLathe and the Turning Operations into two separate addons.

Longer term the plan is to have LibLathe as a separate addon anyway.

Thanks,

Dan

[Kunda1]

Ok great. If not I could split LibLathe and the Turning Operations into two separate addons.

I checked the src/Mod/AddonManager/ source and it doesn't look like it pulls submodules. But I may be wrong.
+ I don't know about the new Extension Manager.

[dubstar-04]

Post for discussion of PR to enable face selection for job setup.

https://github.com/FreeCAD/FreeCAD/pull/4003

Demo:

AxisSelection.webm

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