Alrighty CD Community, does your team have/use custom wheels? If so; What is your process in designing/making them?
Here is a peek at what Team 316 will most likely be using next year.
They are cast urethane plastic.
Do you have any issues with the material being worn out?
The tread or the plastic?
The tread, yes. Plastic, no.
How did you come up with the design for the wheel and do you have the numbers that would show how durable it is?
For the design, I just used the same outer diameter as the AM performance wheels and the bore will snuggly fit an AM hex hub. The spokes are just a simple pattern I drew up.
Not currently. I am trying to learn to use the stress analysis tool in Inventor. I made a set of urethane wheels that are considerably weaker due to air bubbles and they held up fine in a few off season events.
Any details on how these were made? I assume you had to create some sort of mold, but how was this done?
I have been seeing a lot of different types of traction this season too… Which surprises me, then again it is my first year. But I would like to know what other tractions that are available / teams used!
Justin and I have been toying with carbon wheels (145g) including tread material on a 4 inch wheel.
its cool but soooo hard to do
Can’t speak for 316, but I expect it’s very similar to this.
Yes basically, but we are using a two part mold. I will explain in a bit more detail when I get home.
We built these wheels after we got tired of re-treading our Vexpro wheels.
The idea is that they split in half off the axel, so the axel doesn’t need to be pulled out (We use a 2x1 Aluminum extrusion on both sides of the wheel axel) Then we can easily drill out the pop-rivets and replace the tread. As of now, we have had no issues with the tread bubbling at all.
The hex was broached after this picture was taken, we built 4 of them in house (3 Axis CNC), then a sponsor built the other 4 (5 Axis CNC).
And all the Conversational code to build these wheels was hand written, which is pretty cool!
Do you just tread each half and attach them with 2 seams in the tread? Pretty clever for those -hard to replace drivetrains
Did you have any issues with the flat on the top/ bottom of wheels? How exactly do you replace the tread? Is this on a live axle or dead axle?
Wicked cool design BTW.
EDIT: didn’t read whole post. Dead axle then.
Has anyone tried using another material besides wedgetop or roughtop?
Blue Nitrile. That first picture in this thread shows some, though it’s just about indistinguishable from the wheel. Lots of teams use that.
Interesting, Most wheels tend to wear out from my view. Our team uses custom wheels with Ployurethane and they’ve got perfect grip and don’t tend to wear easily.
Polyurethane is a great material; we did a Cinco de mayo parade with the robot last year on a hot day and walked on the streets and our wheels didn’t wear at all. We’ll Be doing the parade this year again ( Tomorrow )
I am not going to go into too much detail because I will make a more detailed thread when they are complete.
To make the two part mold I started off by building the clay half way up the master wheel. http://i.imgur.com/Y1UbrUj.jpg After a good coat of mold release I poured half of the silicone in. Those dimples are called keys, they keep the two halves aligned.
After it cured I took the clay and master wheel out, cleaned up the mold, and put the wheel back in. http://i.imgur.com/TyhgwAN.jpg The rest of the silicone was poured in and 20 hours later it was done. This was the finished mold http://i.imgur.com/FmC5ng8.jpg It didn’t turn out very well because I rushed through the clay part.
There is also this stuff Green Grippy Tread 1 in. Wide 10 ft. Long - AndyMark, Inc
I felt it on 1218’s intake roller and it seemed really grippy and soft. I am not sure how well it would hold up on wheels.
I saw these at champs and they were awesome. Here they are with the tread attached. http://i.imgur.com/3W0z2Ik.jpg
Live-axle version of 971’s wheel. Tread is blue nitrile attached with a zip-tie. If your team has the resources to do this, I highly recommend it; not having to use rivets is excellent.