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problem with "Step Rotating" groups (by Daniel Herring)
(preamble: WOW! There's a lot in this small application. I really like the UI, documentation, and overall finish.)

I'm trying to design some simple parts in SolveSpace. The basics are working smoothly, but I'm having trouble with "Step Rotating" groups.

One part has three tubes arranged around a triangle. See the attached file. For some reason, the rotated groups are not rendering correctly. When I activate g007, things look as expected. When I activate g008, things are understandable. When I activate g009, it looks like g007 with some extra curves but no extra solids.

Any ideas on what I did wrong?

I finally found the right way to do this particular part: extrude the full cylinder as one piece in g004 instead of subtracting g006 from g004. However, I'm still interested in the above answer as I have other parts that do not allow such solutions.

Wishlist: It would be convenient if I could somehow join multiple groups together (or at least activate both groups) and then rotate them at once.

Finally, I'd be happy to hear any recommendations on the best way to replicate gear teeth around a circle.

Thanks for the help,
Daniel
Wed Nov 6 2013, 22:35:00, download attachment ef2.slvs
(no subject) (by Jonathan Westhues)
Step and repeat (either rotating or translating) works on the curves and solid model generated by a single group. So if a feature is made with two extrusion groups, then two groups are necessary to step and repeat it.

In a step and repeat group, the solid model starts from the group that's stepped and repeated, and not from the last group in the list. When you step and repeat the cut in your file, you start from before the step and repeat of the cylinders, and therefore lose the two copies. You can fix that by changing the order of operations from {extrude, extrude, step, step} to {extrude, step, extrude, step}, as in the attachment.

To step and repeat geometry defined by multiple groups in a single operation, you can draw that feature in a separate file, import it, and step and repeat the import. Within a single file, SolveSpace's feature tree is a "feature linked list"; any sequence of operations (step and repeat, Boolean) not expressible in that form requires the use of multiple files.

SolveSpace can't exactly draw typical (e.g., involute) gear forms. You can approximate them very closely with a spline curve, though.
Thu Nov 7 2013, 02:23:13, download attachment ef2-alternate.slvs
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