Need Help!- Rotary Broaching

[inertialabs]

I have a job I am doing and the part needs to be internally broached T60 I am interested in rotary broaching the parts in my machine I found a company that makes torx rotary broaches and when I was speaking to the salesman he thought that I might have trouble overloading my servos I found this unlikely but I have no experience with this at all so here it is

Haas VF3SS
T60 rotary broach
303 Stainless Steel part

Thanks in advance

[omy005]

Max thrust for Z axis is 3923 lb, maybe compare that to a Lathe z axis thrust that is known to work with the broach.

Andrew.

[inertialabs]

That is a good call I will look into it for sure
The guy that makes the broaches was more concerned with the X & Y holding force
I guess is because it creates a huge side load on the part as it works

[Donkey Hotey]

I guess I don't see how rotary broaching would cause any side loads. I thought you were asking about Z axis loads as well.

[florida]

I agree, side loads are a minor issue compared to factors like depth, material and pre-drill size.

[widetrack]

There is some side loading that goes on, but I dont think it will be a problem to you. the z-axis load is easily controlled by feed rate. How hard is the stainless? high speed steel is usually used for rotary broaches, and is about 47C. There are some carbide tipped broaches, but chipping is the real problem there. Your stainless will like to see a 3 degree hook min, and make the bore is as large as possible. If you are going to a shoulder or blind hole, do the broach in steps, for deeper holes, with chip clearing in between. and make sure you follow with an e.m to remove the last burrs. I have broached alot of aerospace parts for rosan ports. usually in 15-5 stainless. Currently working on Hy-Tuff which is the same hardness as the broach. thinking we may have to edm our own broach out of 300 m and take it to about 60C.
good luck.

[Ydna]

How big is the broach being used?

[inertialabs]

The broach is a through hole .5 deep and it is called out at Torx T60 in 303 SS
I have not found anyone that actually makes the broach yet does anyone know of a company that makes an off the shelf cutter for this ?

[widetrack]

Well the thru hole makes it alot easier, and it's a torx shape, so there isn't a big load on the broach either.
a search on the net will turn up different sources, Polygon solutions would be a good place to start. They have off the shelf broaches, and can do customs if necessary.

[KenFoulks]

Originally Posted by inertialabs The broach is a through hole .5 deep and it is called out at Torx T60 in 303 SS I have not found anyone that actually makes the broach yet does anyone know of a company that makes an off the shelf cutter for this ?

Slater Tools Internal and External Rotary Broaches

Slater Tools is the company I use for this type of work. They have a tool-holding system that reduces the load.

Another solution is two broaches (rough/finish).

[inertialabs]

Thank you for the tip I will get in touch with them

Have you done any projects similar to this ?

If so can you give me an idea of how many parts I could get out of a setup like this I know that there are a ton of variables but a rough guess would be appreciated

[kroush]

You could also try Polygon Solutions. Their holder is better built than Slater's Holder and it is grease-free!