What type of steel are gears commonly made from?

[Joe Johnson]

Unless I know otherwise, I have used 60Kpsi as my yeild for the steel teeth I buy off the shelf.

It is not perfect, but it is probably close enough for my purposes.

As to using the Lewis equation, this is WAY WAY WAY concervative. I approximate the tooth as a beam with the load a the pitch line. I use Mc/I for my max stress condition.

I know these are pretty rough approximations, but they work for me (both in my day job and in 9 years with FIRST).

As to static/dynamic loads, I pretty much just design for stall torque with a whatever safety factor I feel I can sleep with.

Weight matters in FIRST. I try to balance a robust design with one that is not so overdesign it makes me loose a match because I could not put the right enough of sheilding around some soft bit of my bot.

Everything is a balancing act in Engineering.

Joe J.

[Ashley Weed]

Hey, its Greg P, yes, i am on ashley's delphi name, but AH! i do have an answer!

there are typically 3 common materials...

Brass
Steel
Iron

there are also some exotic materials used too...

lexan (plastics)
titanium alloys

yes, yes made gears outa lexan...go ask team 42 about their HUGE lexan gears...

technically, you could make a gear out of anything. the results might not be pretty, although i give you props for tryin'




~Greg!~