Forging and heat treat questions?

Hey guys;

I was just given 6 planer blades from a local sawmill. (yea) they are
18"x1 5/8"3/8 They had been sitting out in an open shed for quite a while,
with no oil or protection. The exposed sides and ends have some moderate
rust, but no serious pitting, and the insides where they were touching were
not rusted, and had very little staining. From this I'm assuming that they
are d2 or something other than straight carbon steel, otherwise they would
be rusted solid. Since I am just getting ready to forge my first blade
instead of grinding 440c, I figured this would make excellent practice
material, and I can do some destructive testing to verify my heat treat and
such without offending my frugal Scottish ancestors.

Now here's the request. Could some kind soul out there outline for me a
generic forging and heat treat process from start to finish, using a hand
crank coal forge? Also, some ideals on what to look for in quality
control testing, and which way to go to fix problems?

I would like to try for medium size blades, and attempt a differential
hardening to see if I can get a temper line.

If I get enough responses, I'm planning to condense them together, graph out
the heat treat steps and hand it out to my local blacksmith/bladesmith group
(with credit to contributors) and maybe post it on my webpage when I get
enough stuff to make one.

Thanks tons

T. J.


------------------
I love my country! I just don't trust my government!
 
D

Doug W

Joined
Sep 13, 1999
Messages
64
Can I start it out? Unless you are sure of the kind of steel your scrap blades are, I think it is faults economy to use them. ( my ancestors are Scots too!) If this is a first forging effort, I would like you to learn as much as you can from it! My suggestion is to buy some known 5160 (not very expencive and make a good blade!) and start there. If you use a known steel you can predict the result and if you don’t get what you think you should, you have a place to start looking! Just my opinion. I
have a few questions for you so we will all know where to start!

1. Have you ever built a coal fire before?

2. Do you have a forging instructor, or are you on your own?

3. Is you smithy out of direct sunlight?

Before you lite your fire, I am going to suggest a Rob Hudson trick! Forge clay, yeah! Buy some cheap plastilene clay, the kind we used to eat in kindergarten, and using you hammer and anvil, forge it to shape. It’s fast, it’s fun and you will learn about how you smack it to get what. I forge clay to teach and to solve a forging problems.

One more thing, forging is addictive, you may never be the same!! Wait until you have
forge welded, then you are really had!!

Doug
 
Well, the response seems to be running to the "dont frustrate yourself on this for a first project, go ahead and grind it, and find something else to forge" outlook. I may still play with it eventually, but will probably go get some 1086 or 1095 to start on.

I go to a local blacksmith club and have some experience forging tools and fittings and such, and a pretty well equiped forge here at home.

If I knew for sure the planer blades were d2 I wouldn't even consider forging it, I'd grind some blades, do the ht and cryo and sell them, but not knowing for sure what it is, I hate to do that.



------------------
I love my country! I just don't trust my government!
 
Hi TJ

If your scrap blades are indeed D2 then you can grind them if you are careful. Make a pass or two on the grinder then cool the steel. But just go ahead and finish the blades out, D2 can not be re -heat treated very successfully. First you would have to completely anneal the blades then heat treat again. You can not successfully guess at temperatures and soak times on D2. To Harden D2 it must be wrapped in stainless foil(For an oxygen free enviroment)then pre-heated at 1400 to 1500 degrees until equalized then brought up to 1875 degrees for a 25 to 35 minute soak at heat. None of this is practical in a coal forge.

However the planer blades should be at a pretty darn good heat treat value now. Just be careful not to over heat while grinding and you should have a pretty good blade. Probably should settle for a stick tang and really good epoxy for the handle. Drilling pin holes in hardened D2 isn't likely to happen. (Check AT BARR's post on "shafting" epoxy in his tip of the day.

As was already mentioned, 5160 and any of the 10-- series steels will make excellent forged blades.

Hope this helps,
GaryB
 
Who said “don’t frustrate yourself”, not me. I just want to know where you are at so I don’t cover old ground! May the forge be with you!

Doug
 
I thought this topic was going to be a good one, and we would write a book on forging! NO?

Doug
 
You must log in or register to reply here.
Back
Top