Banebots 42mm gearbox: Recommendations for use

[ZZII 527]

We finally got a full, uninterrupted day of practice time to really put everything to the test. With four BaneBots gearboxes (2x56, 1x42, 1x36) on our robot, this was the true shakedown for the carrier plates.

My hardened carrier plates for the 56mm gearboxes held up fine, no noticeable backlash whatsoever. I believe they are of similar hardness to the BaneBots replacements, so I suspect that these will also be sufficient for the case of 1 CIM and hopefully also for the 2 CIM adaptor.

The soft 42mm replacement plate I made is just now starting to show backlash, to the tune of about 10-15 degrees more than usual. I took it apart and there is definitely a bit of a bowtie (sorry, no picture), although it is not in any danger of failing soon. Still, I will be more comfortable changing it out to one of similar hardness to my 56mm plates.

Which brings me to my next point. I have an entire strip (18"x4") of O1 tool steel 5/32" stock just waiting to be cut. I have been cutting small quantities on the waterjet, but I could potentially produce as many as will fit on that stock in one cut. A few issues:

As Dr. Brooks has noted, tool steel is not ideal for this application because it can become too brittle. Tempering back to RC40 can help this problem and the ones I've made have held up without fracturing, but this can't be gauranteed.

They would not be finish-machined (reaming pin holes and filing double-D). I would only have time for a rough cut on the waterjet.

They would not be hardened. (The steel comes annealed, actually slightly softer than the stock plates, and is supposed to be hardened after all machining is done.) That being said, they may be still useful as spares (I've had one in our gearbox for a week of driving practice and it is just now starting to show deformation) or perhaps others could do the hardening + tempering. (The materials lab I used originally cannot do large quantities and is now in use for classes anyway.)

If teams can live with this, I can start making the rough cut carriers this week and would just ask a PayPal payment or something to cover my costs. Since BaneBots won't have individual spares or hardened replacements for the 42mm, this might be a good option for the 42mm users. But I don't want to mislead people into thinking that these will be simple plug-and-play replacements. I can provide detailed instructions for all the finishing and heat treating I have done, which has held up well in the case of our gearboxes, but I would not have time to actually do it all.

Any suggestions/opinions/comments?