4" Heavy Duty Mecanum Wheels

[Brandon Holley]

Originally Posted by craigboez

I'm actually considering machining one and using it as a master to create a mold from. Depending on how strong that urethane is, especially if fiber reinforced, it might just be strong enough.

I started a project (never finished) a couple of years ago that is exactly what you are attempting here. I designed a 2.5" mecanum wheel and had plans to produce them in a moderate quantity using silicone molds and urethane. The plan never fully materialized, but I do have the "masters" for the molds I was going to make. I hope you get farther than I did! Between school and work, it just completely fell off my plate.

Originally Posted by Tristan Lall

If you mean casting the hub with spokes from urethane, you'll additionally have to worry about stiffness, and then about friction (against the rollers).

Also, such a complicated mold shape will require some creativity to get the part to release. Much more so if you want to avoid secondary machining to get rid of draft (i.e. angled surfaces which make it easier to remove the part).

The urethane is quite stiff actually, and can also be bought in several different durometers.

Also, keep in mind the beauty of a silicone mold is the ability to bend, push and pop a piece out of the mold because of how compliant the silicone is. The Mold Max 30 or 40 from Smooth On holds a very good geometric tolerance.


I think this will definitely be a fun project! Definitely look at team 357's designs in the Behind the Design books. They have already got this process nailed so borrowing some of their expertise would definitely be helpful.

Keep us posted!

-Brando