Help with planetary gear set

I was trying to make a planetary gear set without a chain but what ended up happening was that the motor that spins the carrier didn’t change the speed and also didn’t contribute any speed to the final outcome. But might contribute torque but I don’t know how to test this.
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I’ve already built a working version with the chain and the only thing I did was move the ring gear onto the inside. The only thing that’s connected to the main axle is the 36 tooth normal gear that furthest from the motors. My code basically says to spin the inner ring gear and the carrier gear at the same speed both times except it reverses the carrier gear speed. Which should change the speed of the output. It would be great to know what I’m doing wrong or if having the ring gear on the inside doesn’t work. Also if I forgot to say something then tell me what I forgot.

Maybe the kyle1 guy would help but who knows.

Would you be able to post a video of it working?
When diagnosing a problem, It’s super helpful to be able to see the mechanism working.


This is not how it supposed to work. The direction of rotation for the 36t gears needs to be opposite, and you have them rotating in the same direction.

You will need an even number of 12t gears between 36ts, like this:



not quite what you asked, but in my experience with a similar setup, those small 12t gears aren’t going to last long in there.


Somehow I have a metal 12 tooth little gear.

As do I. They come in the V5 Claw kit.

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That’s where it came from…Also that is why the claw is crappy because we are using a plastic one


They’re super useful, and VEX employees if you’re watching, we would appreciate it if they were sold separately.

Now that we’re on the subject of metal gears, metal versions of the rest of the low strength gears would be amazing. My main issue with the VEX gears is that that bend and the teeth slip, but that wouldn’t be an issue with metal gears.


this is a good idea…

You can buy more here:

You don’t need to buy a V5 claw and take it apart to get them.


I made one of these myself but didn’t use it, so let me know if you get it competition-worthy :smile:

No… you can’t. We’re talking about the small size, but metal ones.

12T Metal Pinion (12-pack) 276-2251 $21.99

The OP picture has them using the 12 tooth plastic to drive the high strength, this gear would be their best choice. Put an insert into it if you don’t want the larger shaft.

the claw comes with a special 12t gear, that is as small as the low strength 12t gears, but is metal.


Yes, what Tobias said. It’s the same shape and size as the plastic 12T gear, just metal instead.


So… why hasn’t vex made them a product yet? Like… besides coming with the V5 clawbot?

Hard to say why they havent. I think a lot of people would prefer them over the thicker ones. Good news is it’s easy to cut a 12t metal gear to make one yourself if you need to

And that is legal? IG it makes sense bc you can cut metal for your robot…

Funny you should say that…

A 12-pack of these gears will be available for purchase in the next few months.


Well that was fast. I should start asking for things more often.