Clawbot "Claw" v2 Gears not Interlocking

We are having an issue with some of our claws. The gears seem to “come out” and are not interlocking like they should. As such, when using the motor to open and close the claw, it is not working as intended. I tried disassembling the Claw to see how it works but I am not getting anywhere. Has anyone had any similar issues? Are there instructions for building the “claw” available anywhere, so that I could potentially fix the issue?

Edit: We are using the v2 Claw Kit.

Are there shaft collars around the gears? I’m not near any of the claws so I can’t give you a detailed explanation, a picture may help though.

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Screen Shot 2021-10-19 at 12.17.50 PM


It appears to not have a shaft collar inside. I would suggest putting one in the space under the motor with spacers. This should hold the shaft in place.

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Just for my own clarification, do you suggest additional rubber shaft collars under the claw or directly under the motor? And do you suggest 0.375 in. spacers? I appreciate the response.

I have continued to try to diagnose my issue. The gears feel stiff and the teeth come out. As I was trying to figure out what’s going on, I was wondering if my screws were too tight. As I disassembled, what I think are tiny spacers fell out (pictures 1 and 2). So I am wondering, do there need to be spacers in the spot I’ve highlighted in the 3rd picture?

I appreciate all the advice I have received so far.

These look more like the washers that come from underneath the screws where the elastic bands wrap round.
If the gears a skipping, it sounds like there is something more fundamental that is wrong. A video showing the issue would possibly help to diagnose the issue.

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Here is a brief video showing what happens. YouTube Video

The first claw is working as intended. The second claw, the red gears fail to move together. This had been happening when operating the built Clawbot. I’m at a loss for why this has been happening.

If the gears have that much slop that they can seperate from each other, it seems like the inserts are missing from the square holes in the red gears and so they are floating freely on the screws. There looks like a lot of friction there. With no motor on, it should just move easily.

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Thank you so much for the response!
Would you happen to know off-hand if there is a part number for inserts that go there?

Here is an exploded view animation of how the the claw parts go together: https://youtu.be/MDEEmq6KYzo

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That shows the inserts nicely. Not sure there is a separate part number for them though.

I want to take a moment to mark this as a solution, and thank everyone for their input.

The inserts that go into the squares of the red pieces, which keep the gears well-spaced and interlocking, are what did the trick. For reference, the part is “0.375” OD x 0.875" Nylon Spacer", part # 276-5918-001.

When I inherited this robotics classroom, I think some of my claw kits became disassembled and the spacers were removed. This forum has been a life-saver, because I was worried there was something permanently wrong with them. Now we don’t have to go and purchase more.

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