turning down dies... the do'd and don'ts.

[maxreloader]

If this is in the wrong area I do apologize...

I would like some advice from anybody that has lathe-turned a commercial die. I have a Star Universal press and I need to take the upper hex off of the sizing die so it can fit into the press. I can add a pic later (its at the shop now) iff needed. Also wanted to turn about 5 thou off of the bottom outside diameter so the dies can get all the way down into the shell plate. I have heard lots of different things about dies being hardened etc etc... but I have only played with a RCBS die and had OK results... The dies in question are Dillon carbide 223 dies. Not cheap so I dont want to booger them if I can help it. Educate me!

[country gent]

It can be done a carbide lathe tool works better than HSS for this. Most dies are tough not truly hard and on the carbide dies I suspect they may be even softer in the body as the carbide is doing the real work. I see no problem with .005 of the outside below the threads. As to the hex its going to start as an interrupted cut as most hobby machines. This will be hard on tools chiping points.

[Walter Laich]

Maxreloader

You in southern Missouri?

[maxreloader]

Southern Maine Walter...

[ulav8r]

Never turn down any dies offered to you for free.

[jmorris]

I have turned a few different brands in the past. If I were going to try and remove a hex on a Dillon die, I would use a tool post grinder and not "cut" it. The hardness and fact that it will be intermittent will not help tooling have a long life.

That said I don't think I would completely remove the hex from a Dillon rifle die. What is it interfering with?

[maxreloader]

It worked just fine jmorris on my humble atlas

[jmorris]

Excellent, my first lathe was an atlas, sold by Sears. Still have it down at the farm.

[1hole]

Every sizer die I've worked with was case hardened so hard it can't be cut with a file or hacksaw. It has been easy enough to work on dies by cutting with a carbide cutter BUT trying to skim cut that glass hard case a few thou has not been successful, the hard case just chips off the softer inner layer of steel. To smoothly take a few thou off the length I have to grind it off.

I've had very good results by lathe spinning a long die body at high rpm and lightly touching the bottom with a high speed grinder spinning a fine grit wheel or even fine (slow cutting) sandpaper. If you try this method, work slowly, it's easy to take off more than you planned.

[M-Tecs]

On the Dillon 223 carbide dies no need to harden the die body. This die uses a full length carbide insert and the body is soft.

For standard dies only wear surface tend to be hardened. Heat Treating cost money so if not need it's generally not done.

[NoAngel]

Before turning down the hex, gently use a bench grinder to remove the bulk it. This will keep the interrupted cut to a minimum.

[1hole]

Every sizer die I've worked with was case hardened. It has been easy enough to cut dies by cutting with a carbide cutter so taking off the hex should be easy. BUT trying to skim cut that hard case has not been successful, the case just chips off the softer inner layer of steel; to shave a few thou off the length I have to grind it off.

For skimming to length I've had very good results by lathe spinning a long die body at high rpm and lightly touching the die bottom with a high speed grinder spinning a fine grit wheel or even fine (slow cutting) sandpaper. If you try this method, work slowly, it's easy to take off more than you planned.

[M-Tecs]

It worked just fine jmorris on my humble atlas

Per the OP this is done without issues. Why would the manufacture harden a die body that uses a full length carbide insert?