Hi CD Community,
We were planning on using a polyurethane rubber roller (70OO durometer, 1/8" thick; McMaster #8514K61) for our intake (on 2" blocks and 2.7" whiffle balls) when we noticed this wear, as shown in the pictures attached, on the roller. The wear comes in two types, one which is more like surface wear (a kind of fraying?) and the other which is the polyurethane peeling off. We attached the rubber to a
TETRIX aluminum tube using superglue (I believe it was gorilla super glue), which has seemed to hold well until recently. Although we have used it a fair amount in testing, we haven't actually used this roller in competition yet, so we are worried that we're doing something wrong with regards to attachment or usage that is causing the said problems. Hopefully this is a clear enough statement of the issue we are facing; please let me know if more information is needed. I couldn't find any other past information here or elsewhere that suggested similar problems, hence a new thread. I'm also posting this here since it is technically a question from FTC, but let me know if there is a better thread to post this in.
My personal guesses as to what could have possibly gone wrong are as follows:
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Normal or excessive wear. Seems rather odd that this would happen, especially since we haven't used it all that much and, as far as I know, a fair number of FRC teams use this as well for intaking.
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Superglue. I haven't found a clear answer on this, but at least some sources (e.g.
this source) suggest that cyanoacrylate (which is a major chemical in superglue) doesn't work well with rubber, while other people say superglue can bond rubber to metal. Could this be the cause, and if so, are there other suggested methods of bonding the rubber to the metal?
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Poor installation. It is possible that we just installed the rubber on this roller somewhat poorly, which might explain the rubber peeling off the tube.
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An accident. Nothing is wrong with the setup, but we may have dripped or rubbed something else on the roller that caused it to react in the way it is.
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Friction with other components of the robot. The only thing it really rubs against is our hopper (storage component for game elements). I don't think it could have been the cause of all of the wear, since it only contacts the rubber in a couple places, but it's possible, I suppose, that the edge of the thin polycarbonate we use could have dug into the rubber.
Anyone have any thoughts on what might be causing the issue? Thanks in advance!
(Also, I think I attached the two images properly, but if not just let me know and I'll find another way to include them)