Est. 1998 — 27 years of woodworking knowledge
A2 Steel
Mike MacDonald
>My Father in-law recently got me several pieces of A2 steel that I was going to make some replacement plane blades with. The machine shop that gave them too him even went so far as cutting them to shape and cutting the slot for the chip breaker screw.
My question is what type of RC hardness will these pieces be, do they need to be hardened and tempered?
They don't appear to have been annealed, and are still bright silver.
Re: A2 Steel
ken c
>Mike,
Most tool steels come unhardened. You will have to harden and temper the steel yourself to make a useful plane blade. There should be plenty of data on the web regarding the hardening and tempering requirements of A2 to RC anywhere from 50ish to 65.
Probably 58-60 would be a good target for a plane blade.
Ken
Re: A2 Steel
Frank D. in Montreal
>Hi Mike,
Just to add to what ken said, you're probably not equipped to harden and temper A2 yourself. Find a heat treater in your area, or call a metal shop and they'll give you a number. Some treaters only take batches (for example, minimum 20 pieces), but many take individual pieces (but some make you wait until they have a whole batch to do). I'd say RC 60-62 is what to aim for, most blade makers seem to harden to that degree.
Re: A2 Steel
Kudzu
>If you have an oven thats all you need for A2. Its an air hardening tool steel. If I remember correctly the shop that used to build for me wrapped it in aluminum foil and put it in their oven. Then took it out and let it cool.
Re: A2 Steel
Ben Knebel
>I don't think you can harden A2 in a standard oven as the temp required is well north of 1000 degrees if I remember correctly--it as an air hardened steel but to get good results the temp drop is a controlled process--again if I remember correctly. We harden our A2 blades to RC58 on the reccomendation of our mettalurgist. Above that chip out of the edge can be a problem. We also cryo our blades.
A2 is definitely not a home hardening steel unless you happen to have a backyard blacksmithing operation.
As I say--I'm working from memory here as I haven't really looked at the process in 3 years---we just send them out to the heattreaters and they come back the way we want them.
Best regards
Ben
www.shepherdtool.com
Re: A2 Steel
Kudzu
>Well I am going from memory too and I think you memory is better than mine. I know the shop we used did their own A-2 and nothing else. But I think your right!
Re: A2 Steel
Ernie Miller Topeka
>Are thoes nail or screw holes? Nails might work out as stress is put on the bench. it is a fun looking bench I like the board jack. can't wait for the top to be finished.
Foil
Jack Ervin
>That foil would be stainless steel heat treating foil. A2 hardens at 1800F and at that temp. tends to burn off the surface in a furnace that is not vacuum sealed or purged with inert gas. A bag folded and crimped forms a small sealed chamber in which the oxygen is burned out before hardning temp. is reached. When the hardning temp is reached the bag is ripped off (foil is .002" thick and easy to tear with pliers and/or tongs) and the tool steel is placed on a fire brick or sutable surface with good air flow. A fan will help the air circulation.
The process in general
Jim Reed @Tallahassee
>Heat treating has several steps:
1. Heat evenly until the steel is non magnetic (probably around 2000 degrees), 2. quench--for A2, quinching is via compressed air, 3. Temper by raising the temp to proper temp for your required hardness(probably around 500 degrees), 4. slowly cool for several hours. I would go for RC58-60 or RC60-62. Depends on the steel; you need to experiment. Too hard and it will crumble during use. Also--most heat treaters have a minimum charge ($75-150). Good luck.
Re: A2 Steel
Kudzu
>I didn't mean to put this photo in there. Must have pasted it in by misteake. :-)
But those are screws that will be plugged once I am convinced I like it.