Wheels..

Well, it’s Christmas Eve and I’m really bored, so here goes.

W-treaded Versawheels-
Light, cheap, and very high traction, but the W tread wears faster and needs to be replaced more often than most other COTS wheels on the market. (source: 341)

Colsons-
Slightly less traction than Nitrile, but friends who use them say that their wear properties are quite nice. I remember 11’s driver telling me that their 4" Colsons were worn way down after the offseason ended, but they did 1 regional, 2 districts, state championship, Worlds, IRI, and 30 hours of driver practice with the same set of wheels. So, I’d say that’s pretty reliable. Sanddrag’s correct to say they’re heavy, and the press fit hubs that WCP/VEX sell don’t help with that.

One of the Colson wheel’s biggest boons is the fact that they have REALLY nice traction on the plastic surfaces that FRC loves to implement (HDPE/lexan on the Bridges in 2012).
I’ve seen 11 and 228 cut diamond tread patterns (using a table saw) in their Colson wheels in order to boost their CoF on carpet. Not sure how much it helps, but I’ll leave that topic to someone who has more experience with that practice.

Freakishly Huge Skyway Wheels-
Unless you’re 25, I wouldn’t bother. Using massive wheels like this is a lifestyle choice that I can’t personally agree with; however, since this is America, they can make their own choices. Not for WCD use for sure.

Higrip-
Haven’t used the new ones at all, but they’re rated to a higher CoF than the old ones. 111 has been using the old kit wheels in our swerve drives since 2007, and we also had them on our Logomotion robot. Benefits are cost and ease of use, for sure. CoF on carpet has improved from the old design. Team 20 broke at least two of those 6" wheels at 2013 IRI, not sure if they decided that the ones they had were defective or not. Regardless, not a bad choice for simplicity’s sake. Solid all-around wheel choice, and easy to fall back upon if you decide to change wheel types.

Vexpro Traction-
Drilling rivet holes is annoying. That said, this ain’t a bad choice if you want a cheaper wheel that can take a removable tread. Very nice wheels when it comes to versa(haha)tility. The new tires (no rivets required) they sell supposedly have a CoF close to Colson tread, but last I checked, they haven’t released the specs yet. I also like how you can make wheel width larger by adding more slices of plastic (included) to the center. Definitely worth looking into. Plus, it interfaces with all of the VP lineup, so that’s another positive.
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Performance wheels**-
I’ve heard negative things about the current implementation of the AM Performance wheel’s tread attachment method. IIRC, teams like 2338 said they had issues with throwing tread very quickly. If you buy these, you’re gonna want to to drill into the wheels and rivet the tread on =/. Otherwise, great wheel. Very nice, very robust, never heard of one of these guys failing. Has a hex bore/key bore (hint: use hex =D) cut into it, so no hubs required for purchase.

I’m not sure if Andymark still sells the performance wheels with the old style of tread attachment. If yes, get 'em. You’ll be doing yourself a favor.

There’s really no point in cutting your own wheels, unless you have crazy awesome resources and a very specific design goal in mind (cough cough 971). COTS wheels will get you where you need to go (design-wise) 99.99% of the time.

There’s two main types of conveyor belt material that FRC teams like using on their treaded wheels: Roughtop and Wedgetop

The roughtop tread VEX sells is REALLY soft. Soft to the point that we were wearing that stuff out really quickly.

Blue nitrile roughtop is what you want if you’re looking for the best conveyor belt tread:

Stuff’s VERY grippy on FRC carpet. If you use it with thicker wheels (~2"), you might experience more wheel scrub, so be aware of that and compensate by increasing your wheel drop to ~3/16 if that’s the case.

Wedgetop isn’t as aggressive of a tread on carpet like the roughtop product I mentioned; however, like Colsons, they stick better to non-carpeted surfaces like HDPE or Lexan (IE 2012 Bridges).

When/if you’re cutting tread to size, I recommend using I trick I saw on here a while back: put the tread rubber-side down on a piece of butcher paper and stick it on a bandsaw. the paper will benefit you twofold: the rubber won’t make a mess everywhere, and you won’t have to worry about the rubber tread getting hung up on the work surface of your bandsaw while you’re cutting.

If anyone’s got issues with any of this, be sure to let me know.
Hope this helps!