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I'm trying to design a "Lifting Table" in OpenSCAD which will consist of 2 concentric cylinders. On the inner cylinder I plan to mount 3 un-powered bevel gears vertically plus a 4th powered one each at the proper location/angle to interface with external cylinder's spiral bevel gear and keep the external cylinder level.

OpenSCAD's involute_gears library makes a bevel gear pair that is close to what I need, but the bigger gear is flat instead of a spiral. How can I get the bigger gear to be a spiral and more than one rotation (level) 720 degrees for example?

  • Did you get the parametric file for OpenSCAD? Have you found the parameters which represent the change you'd like to make? – fred_dot_u Dec 29 '19 at 18:50
  • I think I did, I'm using involute_gears.scad for the parametric file. I have not found parameters to make a spiral gear. – Alan Kwiatkowski Dec 29 '19 at 23:30
  • What I picture you are seeking is a large diameter worm gear pinion (bigger gear in your question) but with teeth instead of a flat surface. That's going to be quite challenging! – fred_dot_u Dec 30 '19 at 00:00
  • Are you looking for a library like [this parametric "Gears Library for OpenSCAD"](https://www.thingiverse.com/thing:1604369)? – 0scar Sep 10 '20 at 07:47

1 Answers1

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I read this question a few months ago, and thought I knew what you wanted. Re-reading it now confuses me a little.

But, I think you may be asking for a large, flat surface with a spiral in it, like the tightening mechanism in a 3-jaw chuck. In effect, are you using the large cylinder as a worm gear to drive four gears which ride on it?

I thought you wanted more general bevel gears, and today I found a package in OpenSCAD that looks quite good. it is found at: https://github.com/dpellegr/PolyGear

If this is the answer you were looking for, great. If not, please comment here and I will delete this answer.

cmm
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