Meshing gears


I have a problem with gears(meshing gears).

An example:
Two gears, one main gear(big), and a pinion(small).
I create the gears using the gears script(wonderful script). This produces two perfect gears, that will mesh perfectly.
The problem is that I want to set the rotation using constraints.
Now, this isn’t a problem using copy rotation and using the pinion as the “driving” gear. I simply calculate the gear ratio; example 20 tooth main, 12 tooth pinion == 12/20 == 0.6. 0.6 is the gear ratio, and I simply add that to the influence slider. This produces a perfect meshing while rotating the pinion.
But, a lot of times the pinion isn’t the driving gear.
That puts us where the “real” problem is; calculating the gear ratio using the main gear as driving, the gear ratio for the above example gives; 20/12 == 1.666666667. So, the pinion should spin 1.666666667 times faster then the main gear. But, here’s the deal; The influence can’t be set to more then 1.
Anyone have a clue on how to set the influence to a value greater then 1?

Since I’m old, and have to see what I do, i really need the gears, and such to show up in my designing stage, not just when animating. So, when I rotate something in blender, i need to see the results as i go, to make sure everything works as planned.

So, any help would be appreciated.

Well, i guess I have to answer my own question:)
It’s solved now. I wrote a script that makes the gear mesh perfectly, no matter what gear is the driver, and It lets me run it in design mode.


I didn’t have an answer, but subscribed to the thread. I would be interested in exactly how you solved this if you are willing to share.

Thanks in advance!

Of course i’ll share. Let me just add some more code to the script, and make some comments in it before i release it. Right now it’s pretty static, only handling one axis of rotation and so on.

Cool! .

Ok, i added the gears script to

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