How do I create this flat gear

SketchUp
1

This is an anti-rotation gear. I am actually trying to create the other side of this, but I can’t get a picture of it but it mates with this so that should be sufficient. They are screwed together to hold the parts in place so they don’t rotate.
The other side has this pattern going about 3 times farther in and it gets shallow nearer the center. The valleys actually appear to rise.
But all I really need is the mate to this. I just am lost as to how to create this.

IMG_20200703_205050
IMG_20200703_2050501117×882 188 KB

It is about 15 mm dia and the gears are about 1.5mm long and 0.25mm high. every 10° = 36 of them.
thanks.

2

Start with a circle made of 36 segments and model one tooth then array it around the circle.

3

This is the basic structure with no specific sizes, you can make the tooth as detailed as you want.
Flat gear

4 Likes
4

Box, you did it again! How do you make it look so easy…
thanks
When I do the rotate and enter 35x it does not create the other 35, it just moves the 2nd one over 2 slots. What did I do wrong?

5

never mind it worked the 4th time.
thanks

6

If you make each tooth as a sketchup Component then you can edit it later and adjust the angle of the tooth, or size, or add bevels, or whatever. (is this for 3d printing?)

Also you will most likely want to model it in Metres, then convert back into millimetres once you are finished. SketchUp doesnt like sizes as small as 0.25mm.

7

thanks Sam. Yes, it is for 3D printing. It needs to mesh with an existing part so no need to mod it and I suspect it is easier to recreate it if I did. And Box’s method didn’t work the first 3 times because it was too small.