Pulley and Belt System Adapters

[snyder.wths]

For our shooting system, we are trying to operate it with a pulley and belt system. With our prospective motors, we would need to adapt from a 1/8" shaft diameter to possibly 1/4" -1/2" (the final diameter from the pulleys is subject to change). So, I am asking if anybody has an effective way of adapting from a 1/8" shaft diameter to any greater diameter. Any products or tips will be helpful.

Here are two links to two of our prospective motors:
-http://banebots.com/p/M7-RS775-18
-http://banebots.com/p/M5-RS550-12

[DonRotolo]

You need a shaft adapter.

To adapt a 1/2" pulley hole to a 1/8" shaft, you take a 1/2" piece of shaft and drill a 1/8" hole in it. Add setscrews to hold stuff together.

A 1/8" shaft is very small, and any pulley with a 1/2" bore is kinda big. Plus if you're using a motor like the RS550 or similar, the top speed is many thousands of RPM, making very precise balance of all components very important.

In other words, you can't just slap it together and expect it to be good.

[Retired Starman]

An easy way is to get a bronze bushing with the correct inner and outer diameters and length, and press it into the pulley. Next redrill the set screw hole and tap it all the way through the bushing. If the motor shaft is really small, like 1/8 in., you might want to drill all the way through and install two set screws. I'd also use Lock-Tite to keep the set screws in. The neat thing about this method is that the bushings are quite precise and will center your shaft in the pulley.

McMaster Carr, and others, have these listed, I think, under "bronze bearings".

As mentioned above, watch for other potential problems.

Dr. Bob

Chairman's Award is not about building the robot. Every team builds a robot.

[Jengles]

My team did the same thing but from a 1/2" to a 5/8". Go to McMaster-Carr and order 6391K113, or any of the others depending on the length.