Brass

[dlane]

Milling 50 bmg brass shell casings for bottle openers , getting a bad finish at end of cut.
Using 9/32 2 flute mill ,holding them in 5c collet holder with thin leather wrapping shell
clamped in the vice at 45deg. Milled in one pass , seems to work ok except the mark left behind when comming out , any suggestions ?.

The mark is on the exit side
Thanks
Derrick
Ps. The avatar is 29 dodge going to show

 

[Tony Wells]

If you can stand to widen the slot a few thousandths, move over and run back through.

 

[Terrywerm]

Might have to go to a smaller end mill and make multiple passes if you cannot stand to widen the slot a bit. Looks to me like the casing is moving a bit in your setup, so it is possible that the problem may occur even with multiple passes, but I doubt it.

 

[T Bredehoft]

Ps. The avatar is 29 dodge going to show

What, not driving it? (It appears to be on a trailer)

 

[brino]

Nice close-up shots, it's like being there!
That will definitely help getting useful answers.

What RPM and feed?

-brino

 

[PatMiles]

Sharp 4 flute endmill, faster speed, slower feed?

 

[ELHEAD]

What, not driving it? (It appears to be on a trailer)

Trailer queen?

 

[dlane]

Next time I'll try a smaller end mill and two passes , or a four flute at higher speed . These casings have a taper to them so the collet try's to hold on the front , I might try to taper a e collet for them also
These were kind of a rush job I cleaned them up with a file.
Thanks
Derrick
The car isn't registered or finished yet
It dose run

 

[T Bredehoft]

The car isn't registered or finished yet
It does run

So long as you plan to drive it , Trailer Queens are the domain of the idle rich. Nobody here qualifies. We're not idle.

 

[royesses]

So long as you plan to drive it , Trailer Queens are the domain of the idle rich. Nobody here qualifies. We're not idle.

And not rich, speaking for me only.