Ideas for Machining this profile?

[VTM]

Looking for Ideas on ways to machine this profile. The material is 303SS. Qty. could be anywhere from 4 - 100. Much larger down the road. The part is .400 Thick and It is a thru hole. We have some Ideas of our own. But would like to hear how others might do this.

Your Input Is appreciated.

 

[rklopp]

Wire EDM a cylindrical slug as long as possible and part off in a lathe.

 

[crossthread82]

Burn job all day long. Either like above wire a long piece and part in lathe. Or mill a plate to 0.400" thick and run them in batches in the wire.

 

[Ox]

If you have a C axis, you might want to ping the Schwang (?) folks.
I think that they make custom broach tooling?


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Think Snow Eh!
Ox

 

[VTM]

I'll elaborate a bit. There is more to the part. But I can't post the whole thing. Basicly It doesn't lend to burning the profile In a long cylinder and parting off. The part is only partially round. But the profile could still be wired, you would just have to do them Individually.


If you have a C axis, you might want to ping the Schwang (?) folks.
I think that they make custom broach tooling?

Unfortunately, No C axis here.

 

[RJT]

Not much other option than wire EDM or broach. Can you stack them up and wire several at a time?

 

[DouglasJRizzo]

Looking for Ideas on ways to machine this profile. The material is 303SS. Qty. could be anywhere from 4 - 100. Much larger down the road. The part is .400 Thick and It is a thru hole. We have some Ideas of our own. But would like to hear how others might do this.

Your Input Is appreciated.

Dad used to use a Fellowes Gear Shaper to generate forms like that.

 

[VTM]

Not much other option than wire EDM or broach. Can you stack them up and wire several at a time?

They could probably be stacked. At least that would be more productive than burning one at a time.

 

[VTM]

Dad used to use a Fellowes Gear Shaper to generate forms like that.

What about tooling? You'd have to have something made I assume. I have had a static broach quoted that would allow us to broach it In a mill with a rotary. About $700 by the time you buy the broach and the holder.

 

[SeymourDumore]

They could probably be stacked. At least that would be more productive than burning one at a time.

Well then, @ .4 thickness and approx 100 pc lots, there is not much debate as far as I am concerned.
Stack 6 pcs at a clip and wire it.
Did not run the numbers, but guessing a sub 1 hour burn @ 2.4" thickness .... so 10-12 minutes/part?
Need tolerance and a single skim cut ... 15 minutes/part?

 

[sfriedberg]

If your numbers get bigger, a push/pull broach rather than a rotary rotary may be more cost effective, even if you have to acquire a broaching machine. That would also eliminate any issues like profile twisting (helix) that you might encounter with a rotary broach.

As for burning the internal profile and parting off, you should be able to make a dedicated lathe fixture that will properly locate your arbitrary external profile. Dealing with asymmetric parts with overhanging features, etc, was bread-and-butter in the days of production chuckers like the Warner&Swasey manual turret lathes.

 

[Ox]

For "much larger down the road" then a pull broach might work/be worth the investment?
That .400" thickness is pretty thin for a broach I would think...
If the parts are stackable, then that would solve that problem...

Check with Ohio Broach for a quote on that.
They can actually doo the broaching as an outside service, not just supply a tool.
Maybe worth starting with if you are sure that you are going to use that same profile in production...


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Think Snow Eh!
Ox

 

[VTM]

If your numbers get bigger, a push/pull broach rather than a rotary rotary may be more cost effective, even if you have to acquire a broaching machine. That would also eliminate any issues like profile twisting (helix) that you might encounter with a rotary broach.

As for burning the internal profile and parting off, you should be able to make a dedicated lathe fixture that will properly locate your arbitrary external profile. Dealing with asymmetric parts with overhanging features, etc, was bread-and-butter in the days of production chuckers like the Warner&Swasey manual turret lathes.

I agree with the push/pull broach for larger qty. I'm still steering away from the parting off Idea though.

Our first Inquiry was a Rotary Broach.This is what I was told.

"The form looks good for Rotary Broaching! However due to the material and size form, the pressure required to create it could be too excessive for the Rotary Broaching process."

 

[VTM]

For "much larger down the road" then a pull broach might work/be worth the investment?
That .400" thickness is pretty thin for a broach I would think...
If the parts are stackable, then that would solve that problem...

Check with Ohio Broach for a quote on that.
They can actually doo the broaching as an outside service, not just supply a tool.
Maybe worth starting with if you are sure that you are going to use that same profile in production...


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Think Snow Eh!
Ox

The profile has been proved out. So I'm as sure as I can be about that. However, we all know, nothing Is set In stone.

 

[SeymourDumore]

I'm still steering away from the parting off Idea though.

Nah, no need for the parting off on this part.
That has benefits if you cut an outside profile, but for this you can conventional machine everything but the "spline", and then easy fixture to stack+wirecut.

 

[crossthread82]

I'd cut the spline feature in the wire first. Stack 12x12 plates about 6 high and burn the inside and then the outside rough profile, dropping 6 out at a time. Then fixture as necessary to finish. (miteebite expanding id clamp machined to the spline profile?)

 

[DouglasJRizzo]

What about tooling? You'd have to have something made I assume. I have had a static broach quoted that would allow us to broach it In a mill with a rotary. About $700 by the time you buy the broach and the holder.

There may be something close in the ASH gear catalog, or have it made. Either way, it's a short process - about 6 minutes total - to generate in the shaper.

 

[VTM]

There may be something close in the ASH gear catalog, or have it made. Either way, it's a short process - about 6 minutes total - to generate in the shaper.

So I'm looking around at these machines a little. Might be a worthwhile way to go for production. Looks like a #3 would be plenty big enough for this part? What do you think?

 

[DouglasJRizzo]

So I'm looking around at these machines a little. Might be a worthwhile way to go for production. Looks like a #3 would be plenty big enough for this part? What do you think?

Worth a close inspection. Dad had 7 of them, varying sizes. Money makers, they were.

 

[EmanuelGoldstein]

So I'm looking around at these machines a little. Might be a worthwhile way to go for production. Looks like a #3 would be plenty big enough for this part? What do you think?

I don't remember the 3's doing internal and they are less common. Probably go with a 7 but it doesn't need to be the heaviest-dutiest one, just needs the hollow cutter spindle.

A cutter is going to run you at least $500 if you get from any US supplier tho. Maybe half that from China. The worst thing about that is, it will be fragile as hell. Not for cutting, that's no problem but so easy to snap when doing setup or you forget to raise it all the way before backing out to remove the part

If you plan to do a lot, then an internal broach would be the ticket. Screw all this wire edm stuff, unless you just need to make a few.