Question: Question about tool steel

[AndrosCreations]

I have some dies that I want to engrave (for striking) and the background has to be a high polished mirror finish.

Mild steel has worked decently but the perfect mirror plane gets a little warbly/distorted after not many impressions.

I'd heat treat a die but heat treating would pretty much ruin the finish and it has to be done post-engraving obviously. ...and I can't rebuff the top with the engraving in place.

Is there a tool steel that (in its annealed state) is tougher than mild steel is?

Thanks for any help.

 

[Ron Spokovich]

I'm not exactly sure of what you want to accomplish here. Although you get some discoloration after heat treatment, that can be polished out by hand, but it's tedious. If already hardened, you're not going to cut it with any success, with hand tools. There are grades of steel that are in the Machinery's Handbook, and other publications, that are tougher than mild steel. The term 'tough' and 'hard' are not interchangeable. You need to do some research on the steels out there, and be a little more detailed in what you want to accomplish.

 

[tsterling]

There are anti-scale compounds that reduce scaling when heat treating. Brownells maybe, if I'm not having a senior moment? If it's a relatively thin piece (short hot time), I've had luck with the old jeweler's trick - 50/50 boric acid and alcohol - dip or drip onto the metal, then burn off the alcohol, repeat until you get a nice thick white crust. Will melt forming a glassy surface while heating to critical temp before the quench, keeping oxygen away from the steel. Also, if I'm lazy, occasionally I just coat with silver soldering flux. Will at least reduce the cleanup.

Good luck!

Tom

 

[monk]

i'd suggest contacting a supplier, describe your needs, and go from there. i'm not up to speed on particular alloys, but i'd bet money there's a few in the annealed state that can be hand cut-- while also being more durable in the striking process.

 

[Brian Marshall]

There are small shops that specialize in hardening die steels (after engraving) - who will, if you contact them in advance and explain your needs - do the work in a way that results in very little scale. Ask about inert atmosphere treatment.

You need to talk to the coin carver who make dies for a living. Sorry, his name escapes me at the moment. One of the hobo carvers will know exactly who I mean... He's posted incredible work on this forum!


Brian


Ron Landis or Steve Adams?

 

[atexascowboy2011]

High temp Handi Flux will prevent scaling.
Don't forget to temper your pieces.

PRACTICE WITH SCRAP PIECES !

 

[Marrinan]

Brain, I think you are referring to Ron Landis. He creates the dies for many of the private mints. He did great presentations at Scott's engrave-in. Showed us the whole process and used to operate a heritage coining firm using all the old hand methods. Heck of a nice guy. Any information I wanted on coining He is the first person I'd go to.- Fred

Goes by Scratchmo on the forum-do a search to find lots of info-FM

 

[scott99]

Hi, you may want to try the A grade steels. They are heat treated wrapped in stainless foil and the scaling is reduced.

scott99

 

[Dave London]

Steve Adams , is a die makers also don't know his screen name

 

[AndrosCreations]

Thanks so much, everyone... Scott99.. Ive been considering that. Because if I use flux /boric acid, I'll have to throw it in the pickel after it comes out of the kiln which would etch the surface and corrupt it in a different way.

I was thinking of using an air hardening steel wrapped in stainless foil.

But, the untreated O1 die I finished tonight hasn't distorted at all after several impressions (like the mild steel would have)... So thats very good! It was just much harder to engrave; I kept break my point.

 

[jeness]

Good advice you have gotten here. If you make a die from air hardening steel, than you can have it heat treated in vacuum, no scale whatsoever, a few minutes clean-up and it is mirror again. A2 steel is relatively cheap, and will last for many many uses. D2 is good too, but will be really hard to engrave, but after hardening it is super durable. I have a knifemaker friend who used to press his makers mark made of D2, and he reached about 50 thousand knives with it before making a new one.

 

[bartelfitzneel]

I really like using 8620 for coin dies.

And, uh, Hi Andros.

 

[Ron Spokovich]

A couple of friends of mine are knifemakers, and have their own Paragon furnaces. They use stainless steel foil, which I understand is in a couple of different grades, and expensive. They place a wood chip, or cigarette butt, IN SIDE THE WRAP, with the blade or object, as the oxygen remaining is consumed with the combustible material. I've seen the blades, and there's no scale and they're clean. You might opt for someone who has an atmosphere furnace, or vacuum furnace, but schedule your work when their doing a batch to your specs as it'd be cheaper. . .you don't want to pay exclusively for the energy used by the furnace! If you're doing a certain volume of work, you may want to consider a Paragon type of electric furnace, and a roll of stainless steel foil. . .not cheap, but you could do your own heat treatment whenever you want. I'm unsure if the molten salts baths would work for your application, or not, but the Paragon may be the way to go, unless you get lucky with a commercial heat treater near you.

 

[AndrosCreations]

Thanks again everyone! I'm slowly working this out.

I wasn't very clear in the original post but was trying to avoid heat treat altogether.

The other day I tried some annealed O1 tool steel (instead of mild steel) that I have for knife making. It was much harder to engrave. Everytime I turned around my graver point chipped... But, after finishing the die and making several impressions, there was absolutely no distortion in the mirror polished field.

Yesterday I ordered some 8620 like bartelfitzneel suggested. It was very cheap in 7/8" and also 1" rod... (and they're cutting it into one inch pieces for me. I'll try to machine down both ends so everythings plumb. I have a digitally controlled Evenheat that I do a ton of stuff in (enamel, heat treat, soufflé)... So I'll get a pail of water and quench the dies.

If this doesnt work, I'll have to buy the stainless foil. I know the paper scrap is a knifemakers trick to burn out any remaining oxygen in the foil.... Hopefully I wont need to spend more on that but we'll see. My bandsaw just died on me today.

 

[LVVP]

Andy,

I never use water for this job, try oil and you will see the difference. The stainless foil trick also help a lot, as you mentioned before.

 

[bartelfitzneel]

8620 is a water quench steel, it doesn't harden well in oil. I use charcoal instead of paper. It sucks up the oxygen very well and has fewer surprise ingredients than paper or fresh wood. But then again I make my own charcoal as well.