Where can I get some gears?

Curl

I need a ring gear but I can't mill it and I don't know any good way to make gears in the shop, so I'm looking to buy them some place, but I don't know where.

I drew up what I need, basically a ring with teeth on it, and a matching pinion.

Attached Thumbnails

 

Ranger Mike

http://www.mcmaster.com/#gears/=8ebl69

Jim1138

WM Berg: www.wmberg.com
Stock Drive Products: www.sdp-si.com

You might need a custom modification which is available from Berg or SDP (I believe)

Curl

I just need the outside/teeth. As long as they are steel/aluminium I can mill off the extra garbage.

Also, has anyone tried to make gears on a waterjet? How well does it work?

Jim1138

Waterjet or EDM cut gears would work for awhile. Not anywhere near an optimal solution. Much higher runout, roughness & friction. Lower tolerance, shorter lifetime. Might be ok for slow speeds and loads.

What are the loads, speed, lifetime, etc? BTW don't mix aluminum and stainless gears, they will gall.

Considered timing belts? They are much more forgiving to misalignment.

Curl

Im new to machining and I'm trying to start up a project and get some practice. I want to make an RC car, I got a nice radio, a 250watt 50g brushless DC motor, low resistance batteries, all the good stuff.

The motor turns at about 1000RPM/volt, and the batteries run at 11-12 volts, so about 10k RPM under load. I need a gear to link straight up from the motor shaft to the differential. The gear I need most is the outer cylindrical shell for the differential, and the gear pinion that goes on the shaft of the motor. The motor has some kick, but I figure aluminium is fine as long as I keep the gear teeth fairly small.

I guess I can polish the teeth by hand after the waterjet to take out the roughness and reduce the friction, then add some lubricant paste. Like I said, I'm very new to this so I need some advice from you guys. I thought of a belt, but how can I make that work in my situation? Is that better than gears for my RPM?

Jim1138

I think you would be better off on a Radio Control forum. Good luck!

Brucer

Curl, How did that go cutting gears with a waterjet cutter? EDM? I'm looking to do the same thing myself.

Curl

I just bought Delrin gears from SmallParts.com
I haven't tried making gears on the waterjet though, but I'm guessing that will work. Our waterjet is broken ATM.