C-Channel Mark

My team built a flywheel, we made sure to use washers and everything, but there is still a marking. What could it be a result of? I attatched a picture.

I mean, a mark isn’t necessarily bad, it’s probably impossible to make a flywheel that leaves no mark, seeing as how fast it’ll spin through that hole. doesn’t look like there’s any erosion on the actual hole, so I wouldn’t worry, as long as there isn’t any bad friction.

oh hi mark

We have this same type of mark! On our bot it’s a shaft collar rubbing on the plate

First of all I would reccomend that you drill holes for every spot an axle goes through. This helps with friction. But regarding the mark, it’s perfectly normal. It’s usually a result of a spacer or shaft collar rubbing against the channel occasionally or always.


We also get these marks, they are normal I think. Also don’t shove as many spacers/washers as you can on the axle, leave a couple washers worth of space free. This reduces friction a lot.

I would not recommend this. It is destructive and unnecessary. The holes are engineered to be used with the 1/8" shafts and bearing flats. Properly installed the shaft will be centered in the bearing flat hole. Holes need only to be drilled to accommodate the 1/4" shafts. Even then I suggest prototyping with the 1/8 inch shafts to make sure you have the correct spacing before drilling.

Yes, First Rule of VEX is always be charging your batteries.

Second rule of VEX is every time an axle passes through a square hole in the metal USE A BEARING FLAT!

In the picture, a single teflon washer should be just fine.

We were disassembling, but we did all of that.

@NyQuil Umm, unless you had graphite on that axle you were not using a teflon washer. They leave a white powder, not black. The teflon washers are thin, hard and white. Is the flat on the other side of the plate? (Love the standard screws)

Thanks! We used the steel ones not teflon, but on the recent one we started using teflon.

I wish I can agree, but because the square holes are so small the slightest tilt of a bearing flat would cause friction of metal-on-metal rub. This means you are having a serious loss of efficiency and this is also one of the causes that a drivetrain doesn’t go as straight or leans a great amount. Because of this small change of just drilling holes where all axles go through for the drive base, I am able to compete against V5 drivetrains and never stall. I never stalled in a match due to that one simple change of just drilling out the holes.

I mean there are guide flaps for inserting the bearings correctly. But this is a good solution and has more room for error.

the current teflon washers (or at least the ones i got last week) are murkish clear rather than white

I find the easier way to align axles is to mount the bearing flats loosely, put something weighty on the axle and spin it, then tighten down the bearing flats when they’re positioned such that the shaft spins freely. Saves time and drill bits. The great part is this procedure can be done on an axle in situ with almost no disassembly.

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You dare question the great @[TVA]Connor ?

Make sure to allow some room between the collar, washer, and c-channel. U don’t wanna push the collar right up against the washer making it super tight. If u leave some space between them it reduces friction and prevents marks likethat

Sometimes the flaps get bent inwards on mine. I sometimes like to just take them off completely on one of the holes and mark it so if won’t add friction to the axel.