Annoyed after years of replacing treads that fall off, I’ve decided that there has to be a better way.
Does anyone know where I could find some “traction” wheels that do not have plaction-style treads? And that would also be easy to interface with AndyMark products(sprockets, etc…)
I’ve heard of colson wheels, but I also heard that they are not the easiest to use “out of the box”?
Preferrably non-pnuematic…
Thanks;)
You could try doubling, or even tripling these wheels together.
Maybe you should look at more effective ways of attaching the tread? The issue with getting a non-removable treaded wheel is that when the tread wears out the whole wheel is useless.
We at AndyMark are working on a new tread-attachment method, using conveyor belt lacing hardware. Here is a sneak peek. Later this summer, this method will be in place for all AndyMark Plaction Wheels.
Sincerely,
Andy Baker
I didn’t mean non-removable exactly, I was pretty much referring to the am-KIT wheels,
I guess what I was wanting is a solid rubber type wheel like those but with stickier material?
Neither link seems to work. 
If you throw out Colsons, I’d probably recommend some kind of polyurethane rubber wheel or something. Before FIRST I used to do a lot of tinkering with inline skate and scooter wheels, which had a lot of the same requirements as an FRC wheel with regards to shock loading, tread wear, traction, etc. They certainly would not work “out of the box”, but you could probably get a company to install an aluminum core with a hex bore or a bolt pattern for you.
Not that I’ve used them on an FRC robot or anything, so no guarantees, but it’s an idea I’ve wanted to try for a little while.
Do you have access to any machining? I would try machining off the regular rubber tread, make a mold, and cast your own tread onto the plastic wheels. There are plenty of cheap rubber casting kits around. Try slotting (in cross-hatched patterns) or knurling the surface of the plastic wheel (with the tread gone) so that the cast-on tread gets a good, solid bite.
A buddy of mine in college made a great casting setup by machining the wheel’s lug pattern into a plate, then boring out a two-part block (with the two halves already bolted together) to the tread diameter he wanted, then he bolted the blocks to the plate.
Robot Market Placehas several options. I have not used them, just pointing out they are there.
An ancient FRC trick: Take a Skyway wheel (similar to the AM KOP wheels of the current day), grind or sand off most of the tread, then screw on belting that is similar to the AM belting strips. When you need to replace said belting, unscrew the screws and grab a fresh piece of tread.
It’s not exactly common for this setup to fall off mid-match–if one end comes loose, you will notice pretty quickly.
It’s just like chain tensioning. If done correct the first time, you will not have any issues.
One of the main reasons that the tread has the ability to be taken on and off is reuse. You can reuse the wheels for as many competitions and years as you would like, just replace the tread.
Hmm, how well do those colson wheels work?
CoF?
Has anyone ever taken one of the kit wheels and cut a tread pattern into it?
Your treads fall off?
We’ve never had that problem and have been using belted wheels for 4 out of the last 5 years.
Are you using large head rivets?
Do you rivet too close to the end of the tread?
I’m curious what your failure method actually is.
During build season we used 1/8th and 3/16th steel rivets, then during ship day and the FL regional the every single tread came off at least once, when one would fall off we would switch it out with a new tread and new rivets, the 3/16th rivets were large head.
The failure would happen when one of the ends would come loose then take the rest with it. Each end had two rivets, in between each spoke would also have two. Most of the time the rivets did not come out, the tread just tore a hole in the rubber around the rivet.
This is odd. Do you use washers with your rivets?
We’ve never had tread really come off, just get so used that it was garbage. Our team also switched to blue nitrile tread and we haven’t replaced the tread from our 2008 or 2010 robot. We have always used 1/8" aluminum Rivets.
I think the key is making sure to use rivets with washers so your rivet doesn’t bore through the tread. Also making sure tread is cut to the correct length helps.
-RC
Might have also drilled the holes one size to large?
We have in the past. It works great until the edges of the pattern wear off, which happens fairly quickly.
How much does the lacing protrude? Would there be any risk of violating, for example:
–Ryan
True, I know that we did this for a couple of rivet holes and the rivets would just pop out freely.
-RC
I don’t think so, but it’s possible.
Finally after I had replaced all of them I put some 3M-2part epoxy on the ends of each, that held them for the remainder of the regional.
I’ve seen a lot of teams rivet too much. Two rivets side by side in 1" is not necessary, we’ve gotten away with 1 rivet centered on the 1" face on each end. If you “cut” the tread too much with holes, it gets weak and wants to start to break apart at the hole.
