Rotary Broach

[ozzie34231]

I'm just a hobby machinist, but it seems it would be simple to make my own rotary broach. Nothing big, internal shapes to maybe 3/8".
Since it seems that way and I see that the prices for such tools are pretty high, I know I must be missing something.
It could be that the bearing system is quite sophisticated; anyone know more about these tools?

Ozzie

[florida]

Get good quality bearings. Polygon Solutions uses FAG brand sealed bearings.

[xero_xero]

I am interested in an alternative to edm and expensive rotory broaches. We have none of either in a large shop. Can I get specifics as to how they work. Possibly an assembly drawing as well. We have an array of mills and lathes of varying sizes. I personally need a broach for 32 mm and 31 splines.

[florida]

Most rotary broaches will only handle forms up to about 1" dia. If larger, the broaching (tooth) height should only be about .010-.030 per side depending on material. You may be better off looking into EDM with 32mm size.