Polishing a die neck?

kamlooky

kamlooky

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Just discovered something today on one of my dies.
How does one go about polishing a sizing die neck area?
Pull the decapping pin and rod, then what?
Roll up some 600 grit paper?
Die grinder with a soft bit and metal polish?

Dang...........TFIF........huh?
 
I think scotchbrite works really good for this. I polish my decapper rod to a mirror finish by putting it in a drill and spinning it in the scotchbrite pad
 
I don't know about a die grinder but I have a Milwaukee 12v "Dremel" type tool and some hard felt bobs. I'd use a bullet-shaped bob and some white rouge, and maybe the very fine green oxide if you want to really put a mirror finish on it. There is some info on polishing compounds here as well as on Grizzly Tool's website. Fine wet-and-dry paper (600 and up, used wet) is great but will be difficult to apply evenly to the inside of a die neck.

:) Stuart
 
Scotch-Brite cut in a narrow strip and wound around a nylon bore brush and powered in a drill works great. Polishing compound will remove metal, Scotch-Brite cannot.
 
Chinbullco said:
Scotch-Brite cut in a narrow strip and wound around a nylon bore brush and powered in a drill works great. Polishing compound will remove metal, Scotch-Brite cannot.
Click to expand...

Very good point. I stand (sit) corrected.. :) For some reason I was assuming the problem was some sort of roughness, although Kamlooky didn't say so.
 
The neck portion of the die, not the body.
Just noticed marks on the neck of brass I was sizing and think there
might be a blemish of some sort in there.
Might try and sneak a thin sliver of Scotch Brite as suggested and give it a try.

Thanks folks.
 
Chinbullco said:
Scotch-Brite cut in a narrow strip and wound around a nylon bore brush and powered in a drill works great. Polishing compound will remove metal, Scotch-Brite cannot.
Click to expand...

Huh? Beg to disagree. Abrasive is abrasive. It works by removing material. Wherever you got that idea from, they fed you a line of poo. If you came up with it yourself, maybe reconsider your line of reasoning.

Scotchbrite is abrasive media on a plastic matt. Still abrasive. They make a bunch of different grades. IIRC the white stuff is a simple plastic pad. But that stuff does nothing. Toothpaste is abrasive, so is valve grinding compound. Lots of grades of abrasives to choose from, lots of substrates too.

'Looky, it would depend on how much damage you have, and how much material you can afford to move. And whether you are trying to fix something, or simply trying to smooth it all out and make it better than factory.

I can suggest any number of ways to accomplish either, ranging from the stuff that has been suggested to some things that are less aggressive, like loading up a wood stick with metal polish and spinning it in the throat of the die, or making an expanding lap and charging it with coarse or fine abrasive powder, and using that.

Cheers
Trev
 
trevj said:
...like loading up a wood stick with metal polish and spinning it in the throat of the die...
Click to expand...

Such as Flitz or Solvol Autosol. The very fine green abrasive I was referring to I think I got from Lee Valley and it is something like .5 micron/9000 grit (although I may be thinking of their micro-abrasive sheets) but it is VERY fine and I doubt it would make any dimensional difference to the die.
 
I found some dents on the shoulders of some cartridges I was loading.
There was a burr and some junk right where the vent holes was drilled (badly).
I contacted Lee and the customer rep suggested sandpaper on a wooden dowel.
Didn't say which grit. Said the die was pretty hard and it was unlikely I would damage it.
I suggested that since it was a new die I would return it for replacement, to which he agreed.
 
Yes the material is extremely hard. I bought a 9mm flex hone to try and hone out my Lee FL 338 die to .365 from .340 and it did absolutely nothing after like 5 minutes on the drill. I'm gonna try again for 10 minutes and see what happens.
 
If you can find some Jeweller`s rouge and put it in a felt pad to spin in that throat,
it should do what you need without any real dimension change.

Regards, Dave.
 
swissinn said:
Yes the material is extremely hard. I bought a 9mm flex hone to try and hone out my Lee FL 338 die to .365 from .340 and it did absolutely nothing after like 5 minutes on the drill. I'm gonna try again for 10 minutes and see what happens.
Click to expand...

If it is a Lee Carbide die, you'll need diamond lapping paste on it, I think! I use a carbide scriber to scribe the backs of sheets of sandpaper in order to cut them because it won't be harmed by the abrasive.
 
josquin said:
If it is a Lee Carbide die, you'll need diamond lapping paste on it, I think! I use a carbide scriber to scribe the backs of sheets of sandpaper in order to cut them because it won't be harmed by the abrasive.
Click to expand...

Not a carbide die i don't think. Just the cheap set! But man its hard material.
 
Went through all my die grinder bits and found a round soft one.
Bit big, so when the tool store opens up tomorrow, I'll see if I can find one
a tad smaller.
Looks like it made a wee bit of difference on the bottom side edge.

Couldn't stuff 'nuff of the scotch brite pad in there and I was thinking
it wasn't such a good idea.
 
I had a set of rough made Lee dies that got a bit of rust in them so what I did was apply some steel wool to a bore brush and spun it with a drill. Then for a high polish I took the same brush and covered it with a clean cotton bore patch with a dap of blue magic metal polish and spun with a drill again. Cleaned up the die interior with a shot of bore cleaner.
Shines like a mirror now
 
You might regret using a "soft dremel bit"
I use abrasive rubber bits to remove material from feed ramps. They can be quite agressive. Try the steel wool and polish applied to an old bore brush idea first. They remove very little material and all you want to do is remove what is quite likely a small rust bloom.
You will never get even a soft bit to conform to the case profile. Not to mention that a dremel bit has a very short shank and won't reach very far inside the die
 
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josquin said:
If it is a Lee Carbide die, you'll need diamond lapping paste on it, I think! I use a carbide scriber to scribe the backs of sheets of sandpaper in order to cut them because it won't be harmed by the abrasive.
Click to expand...

Lee carbide dies only have a ring at the bottom of the die. The rest of the die is standard tool steel
 
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