Wheel Shaft popping out of motor

Any build ideas on preventing this from happening? We tried inserting the metal insert into the motor and using the rubber shaft collars. 2 of our 7 robots continually have the shaft pop out and wheel stops turning. Thank you.

Don’t do this. Use the steel shaft collars, they are much better at holding shafts in place.

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Rubber shaft collars are pretty much for prototyping and testing models (and for IQ). For competition, switch to steel shaft collars: https://www.vexrobotics.com/v5-shaft-collars.html

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Thank you. We have used those, but will try again. Right now our class has the clawbot built – not the competition robots. We’ll see if the steel collars will fit to hold the shaft in.

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I have my kids use the metal adaptor for high-strength gears (I think it comes with the metal 12-tooth pinion). I have them put that into the motor output, then use whatever number and sizes of spacers that it takes to keep it from sliding out. As previously mentioned, the liberal use of metal shaft collars is something that you want to do as well. We try to have one on each side of whatever structure member that the driven shaft is running through - we’ve found that while the new star-drive set screws don’t loosen up as easily as the old style, all shaft collars WILL eventually come loose - so having a backup or two in place works very well.

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I believe the clawbot comes with cantilevered wheels, right? What I like to do is put a shaft collar and teflon washerin the gap in between the motor and the metal its screwed into.

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even better are the clamping shaft collars. steel shaft collars with a tiny but of loctite are also really good.

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Steel shaft collars used properly should be much better than a clamping one. As long as you tighten it down.

Personally, I use a combination of the steel and rubber. I use the rubber as spacers (they are a unique size, at least from the other spacers I have), and it allows for even more security.

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you cant properly tighten the hex drive ones though

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If your build quality is excellent, you can merely grab a metal shaft collar and replace the set-screw with an actual VEX Screw to allow you to tighten the steel shaft collar with higher torque. This should last you almost the entire season without the need to worry about shafts coming out.

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Sadly doesn’t really work when you need to put the shaft collar in tight places… but the set screw still does the job as long as you tighten it.

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I would not use the default set screws as they will strip after 2-3 uses of high-torque tightenings. If you’re using set-screws I would recommend using a T8 driver and star drive set screws by robotmesh.

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I had the same problem. According to the robotics 2 students in my class metal shaft collars are better than their rubber counterparts.

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You’re a bit late but yeah. Anyone who plans to be serious should invest in metal shaft collars. They’ll save you a lot of time and energy later.

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