Wobbly Shaft Issue on '23 FRC Kit of Parts Toughbox


We have found that the steel output shaft (am-4722) used in the 2023 FRC Kit of Parts AM14U5 Chassis ToughBox is causing a problem. The 3/8" end of the shaft is slightly offset (~0.02") from the center of the shaft, and it appears to be very consistent. This eccentricity will cause a wobble on the middle wheel and Toughbox housing on the AM14U5.

We found this out today, and have informed FIRST. Collectively, we will provide more information and solutions early next week. For technical help, reach out to support@andymark.com.

Andy B.
AndyMark, Inc.


The ghost of a quality assurance engineer is going around and making sure no supplier is safe from out-of-spec parts this year. This is the only explanation. I will take no questions.


We’ll fix it with code.


I hope we can find a solution option that can be performed at events - no matter how much effort is put into reaching out to teams beforehand, there’s bound to be some that won’t get the message and will need help fixing it!


I was right! Both Axle wheel not moving straight - #30 by Ninja_Bait

But yeah some spare output shafts and gearbox bodies would probably be good at events. Could see a lot of fatigue failures at events.


Thanks Andy! You rock!


Are the shafts the same spec as prior toughbox minis?

If yes, wondering how many teams we can rally to bring old axles to events with them Incase teams don’t get the memo.


Tomorrow morning I’m going to have the team scour the “archives” for useable shafts.

Yup, we noticed that the other day, and swapped out our toughboxes for last year’s. Sorry we didn’t report it–lots going on.

In my 18 years of FIRSTing, AndyMark has consistently been the most thoroughly-tested, customer-focused, and quatlity-centered vendor we have.

Thank you Andy and team for being models of accountability and responsibility. Current FRC students who will become entrepreneurs will be inspired by your leadership.


Older shafts do not appear to be compatible with the new gearboxes on this year’s KOP chassis. The E clip groove is 0.057in closer to the bearing face on the 2023 shaft vs older ones. So if you want to swap them out you will need an old gear set as well, which could cause some problems as the 23KOP Chassis also has a different gear ratio as prior years.




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Anyone know the difference in KoP gearbox gear ratios from last year to this year? We still have our 2022 kitbot toughboxes.

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Last year: 10.71:1.
This year: 8.45:1.


We’re using the 2023 gearboxes and wanted to use the 8.45:1, but we did NOT use the 2022 gearboxes from the kit. So, we had unused 2022 drive shafts.

We just lathed the e-clip slot to be further back. Its wider now but the gears push the clip against the new limit. It is in the process of testing, but it seems like a “sort of” solution.

Video with no more wobble: https://drive.google.com/file/d/121D03nMXLjPCMSyRjclHkrjWk0oG-uGz/view?usp=sharing

Drove up and down hall, everything seems within normal noise levels and drive is smooth.


We tested the gearboxes in our 2023 KOP chassis and found that the shafts wobble on both gearboxes.

Welcome to the real world, where you can have the most rigorous QA testing process ever conceived and still have issues slip through.

My experience matches others, that AndyMark has had VERY fee issues slip through the cracks over the years, which indicates a fairly strong QA program. Additionally, any time there was an issue identified, Andy and his staff have always been open and communicative about it, and do whatever they can to make it right.

So while I agree the issue you describe was terrible, it was one instance in the entire span of the company’s existence. I dont agree that it means their QA process is trash.


Just to get some clarification, is the posted picture using the 2023 Kit of Parts chassis or the 2022 chassis? The screws that are part of this year’s chassis were extensively tested last summer (multiple hours worth of driving) without any indication of screw backout.

As always, if you notice an issue with one of our products, please contact us (phone or email) so we can help make it right.


I did notice a wobble in our middle wheels today while the students were on the bench testing out drives. I was wondering if they didn’t put it together properly. I’ll take a closer look next meeting and hopefully we can get some proper parts from AM soon.

Here is a video one of our team members made showing what the wobble looks like. We connected one of the NEOs on the gearbox to one of the SparkMax’s for the drive train in our 2022 chassis. The chassis was up on blocks for safety. Both gearboxes showed the same wobble. Some of the other teams working in the same STEM Center came to see what it looked like so they can check theirs.

The only way I found to upload the video was to put it in a zip file. Download and extract to view.
shaft wobble.zip (4.7 MB)

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You could also use YouTube, if you have a Google account that works