This probably a stupid question, but what would the feasibility of 3DP tires for swerve, instead of using Nitrile tread, since black tread tears up our carpet, but blue tread wears out too easily?
There is a 3D-printed TPU90A tire for the Mk4(i) module run by Team 88 during the season, and they just publicly released the CAD today, highly recommend you check it out.
There is so much on this on CD already. I encourage you to do a search.
We had some luck with Hatchbox TPU on our Thriftybot Swerve modules.
They aren’t even close to as grippy as blue Nitrile or Black neoprene, but they seem to last a while and were easier to install. Not competition - worthy, but fine for playing around.
I like this as a use-case for doing demos in locations with concrete or other abrasive surfaces. Swap out our good tread wheels for TPU tread wheels and go nuts.
For years we ran AM high grip wheels on our custom swerve and they performed OK. Then we got brushless motors and cots swerve became common. In 2021 our AM wheels wore too fast and became a problem. Swapped allot of wheels. in 2022 we experimented with different materials and settled on Vexpro hubs and printed 95A TPU. Wear is excellent and grip on poly and carpet is good. This is our wheel solution going forward. After trying several tread patterns we went with the AM high grip tread pattern. They are printed on an Ender 3 that has some mods. .8 nozzle, .4 layer height and slow 30 to 40 MM/sec. There a whole lot of tires on a 1 KG roll. It did take some trial and effort to find the proper print temp. For our printer and filament, 225c but not more than 230c. 3dp printed tires served us well in 2023.
So the TPU works ok on the Ender 3? Also, are you printing the tread as a whole loop, then assembling the wheel around it?
The key to the Ender 3 printing TPU is - All metal hot end with good cooling on the heat sink, High grade bimetal heat break, .8 copper plated nozzle, capricorn bowden tube and a dual drive gear extruder. We print on a rough PEI coated spring steel build plate. TPU sticks well, almost to well. We use Magicgoo PC as a release agent. The .8 nozzle is key as its hard to push the soft filament thru a smaller nozzle. I do not use part cooling. Focus is on strong layer bonding. Don’t try to print fast 30mm/sec is a nice speed.
The Vexpro hubs are 2 pieces and sandwich the tire. They are cots and so far just take abuse. Pictures of the tires.
I would not have posted this earlier in the season. Now that they have been proven thru a season of abuse, I feel that they are a worthy solution.
Heads up. some of our other prototypes turned our FRC robot into a FRC carpet trenching machine. We traded grip for kindness to our carpet. Be kind to the FRC community and don’t field carpet trenching machines.
I’m curious, what infill percentage has worked well for this?
It’s solid by walls. This makes extrusion important. Over extrusion makes a goopy stringy mess.