Workholding 1/2" x 1/8" brass disc.

[klemchuk]

We have a Haas VF4SS with 6" Kurt single station & 2 Glacern 2 station vises mounted on table.
We need to machine .500 dia x .125 thick brass button.
Button needs a recess machined around perimiter .0625 wide x .022 deep, as well as 2 holes d&t 4 48, and a slot in the centre .032 x .250.
The problem we have is holding consistently. We have tried a milled pocket in vise jaws, worked well on a TM2P but not on current machine and we tried holding it in a .500 collet, which didn't work very well.
Can anyone suggest a way to hold these little buggers?
Thanks in advance.

 

[rklopp]

That seems like a job for an emergency collet or several arrayed on the table.* When you say 0.5" collet, do you mean a normal collet with a through hole and no step to fix Z? How many are you trying to hold in each set of soft jaws at once? I hope no more than two. Otherwise, if the job ran well on a TM-2P then surely it can run well on the VF-4. What changed?

*I assume you will probe each part individually to account for Z changes due to collet pullback changing with varying part diameter.

 

[pcd]

*I assume you will probe each part individually to account for Z changes due to collet pullback changing with varying part diameter.

Or get a dead-length 5C fixture.

 

[Ox]

My first thought was a stepped collet as well.
Just get an "emergency" collet and bore as needed.

You COULD bore a small step in a regular 7/16 collet if need be.
They are hard, but you can cut them.
In this case, put a 7/16 dowel pin in the collet and chuck it up.
Measure the slit widths in the collet.
Take the pin out, and slide 3 number drills down those slots to hold at right spot, and close collet.
Then machine...


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I am Ox and I approve this here post!

 

[klemchuk]

That seems like a job for an emergency collet or several arrayed on the table.* When you say 0.5" collet, do you mean a normal collet with a through hole and no step to fix Z? How many are you trying to hold in each set of soft jaws at once? I hope no more than two. Otherwise, if the job ran well on a TM-2P then surely it can run well on the VF-4. What changed?

*I assume you will probe each part individually to account for Z changes due to collet pullback changing with varying part diameter.

 

[klemchuk]

Horsepower and speed, both spindle and feed.

 

[Eleven71Cutters]

I have used blue painters for 1/8" or thinner material, Blue tape on a flat alum plate then blue painters tape on the part. Superglue between them and let it set up. Easy to machine all the way down the part side.

NYCCNC (John Saunders) has a ton of info on this.

 

[kustomizer]

Is the .500 not .500? I would think the problem lies there, is it barstock, punched blanks, what are they?

 

[klemchuk]

Is the .500 not .500? I would think the problem lies there, is it barstock, punched blanks, what are they?

 

[klemchuk]

They are punched blanks. The Kurt vise held them until we moved to the VF4. I'm thinking the faster spindle and/or faster feeds may have something to do with it.

 

[Donkey Hotey]

Why is this not a lathe part?

 

[Houdini]

You already have punched blanks but as Donkey stated lathe, but that would need to be live tooling lathe.
loading bars vertical in VMC and cutting them off with a slitting saw would have been fast 6 bars in 3 vises,
slicing away.

holding in vise jaws should work. one on each far end, make sure you over torque the jaws slightly before machining pockets(remove draft angle)
and since they are punched larger burr side down.

If your using Aluminum soft jaws they will compress/deform over time, and bell mouth, loosing grip.

face off and recut jaws.

shorter jaws work better but cant be cut down over time as the jaws wear out.

thinking out load

 

[Donkey Hotey]

You already have punched blanks but as Donkey stated lathe, but that would need to be live tooling lathe.

We're all guessing what this part looks like. I'm reading the description as an o-ring groove around the outside edge. That says lathe, right there. Turn the end, and OD. Turn the groove. Part it a little thick (+0.010?). That goes into the VF-4 with the unfinished side up. Face. Drill and tap two holes, cut the slot. Done.

 

[Ox]

Wire wheel / [small] vibratory finisher yet....


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I am Ox and I approve this here post!

 

[david n]

What exactly is the issue? Location issues? Are they coming out of the vise? They worked in the kurt vise but not the glacerns? They ran OK in the TM in a vise? You should be able to go right from the TM to the VF machine with the same set up...............

 

[klemchuk]

What exactly is the issue? Location issues? Are they coming out of the vise? They worked in the kurt vise but not the glacerns? They ran OK in the TM in a vise? You should be able to go right from the TM to the VF machine with the same set up...............

 

[klemchuk]

They worked fine in the Kurt vise on the TM2P but not in the Kurt on the VF4SS.
They keep popping out. It's not an O ring groove it's to locate the part in a sheet metal part & allow rotation.
The two d&t holes hold another part to lock it into the sheet metal.