I have inherited three wood planer blades(15"). Can they be used for a knife?
What might I do to them prior to forging?
Anneal?:confused:
I have only made RR spike knives.

Thanx for the help

2DOGS

Hello,

Yes they can be used for knifes, the high end planer blades are made of some pretty good steel. Before you forge them though make sure that they don't have chrome or nickle in them I have never heard of a good planer blade that has those metals in the steel but with all the junk coming from china it is better to be safe than sorry. Annealing is an ok process for mild steels that you are planing on cold forging, but for higher carbons I just cut my working shape, and heat it up; be careful to keep a good temp in the part you are forging as higher carbon steels can crack very easily when hit at a temp too low. also when you finish the knife make sure to harden and temper the metal, mild steels don't need this process (unless you case harden them in vermiculite) but high carbons steels do, as the crystal structure of the carbon is what enhances the hardness of the steel, by quenching you form max hardness, or close to, and tempering relaxes this super hard metal into a more reasonable hardness for what ever you are planing to make, thus reducing the likely hood of your blade shattering. hope this helps

How old are they? A lot of the recent planer blades are HSS and very hard to forge and heattreat, often being air hardening with very narrow forging ranges and esoteric heat treats that really do need to be followed! Some high alloy steels, like D2, can be forged but would profit from a professional heat treat. W1 or W2 can be forged and heat treated by a smith fairly well.

Many if not almost all modern planer blades will have chrome and or Nickel in them for abrasion resistance!

Spark test them and compare to a chart.

Edited December 2, 200817 yr by ThomasPowers

nothing wrong with additions of Chrome and Nickel, Add 3/4% of chrome to simple 10XX series and ya get 5160, add 2% nickel to that and get L6, both of which are great for blades. While this math is not 100% true, it is a close enough approximation for you to understand my point.

Hello:

Hope no one minds...most of the GOOD brands of old planer blades are usually F-8, with around 130 pts C, 4% Cr, 8% W and 25 pts V..Boy are they a real bugger to hand work..but they do cut when properly heat treated.....And the thermal treatment is a bit tricky...

JPH

I was always told planer blades were usualy D2, you can forge it if you like, but I would just do stock removal and go slow so you dont take the temper out ( planer blades are already hardened). Just grind away everything that doesnt look like a knife, lol

THE THREE BLADES ALL HAVE DISSTON 50 PRINTED ON THEM.
I WILL GOOGLE THIS AND SEE WHAT I GET.

WELL.. DISSTON IS AN OLD TOOL MFG. CO. MOSTLY CUTTING TOOLS. I DID NOT SEE ANY DATA ON THEM AFTER THE '40s.
THEY ARE 1-3/16"W X 3/16"T X 15"LONG
@ 3/16 THICK, WOULDN'T THAT BE A BUNCH OF GRINDING?

Edited December 3, 200817 yr by 2Dogs

Please don't shout. FYI Caps lock is bad neticate and very hard to read.

3/16= not a substantial amount of grinding.

Planer blades have some unique qualities about them. They are designed and used for takeing thin slices off of the full width of a log that has been steamed for 24 hours to soften it and prevent seperations. They must hold an edge for the duration of a crew work shift and then they are changed out at start of new crew. At least the ones I saw at work were done in this manner. From that we know a few things. They hold an edge reallly well while working with a abrasive material. There is no bending expected from them so the steel is not required to be soft enough to flex. The materials listed above add to the qualities expected. The steel make up also makes it extremely difficult to grind from a hardened stated into any other form like a knife. As above also is a need for professional heat treat services. Not all are D2 but you can research D2 and see what is involved in that process for an example. AS for forgeing give it a try, see how it works and what you can do with it. Then anneal it, I use vermiculite,(which does not case harden) it allows the slow cooling from non magnetic that is needed to bring the steel to its softest state. Do you grinding then and send out to heat treat. You may have something you can work well with. If anyone wants to stop by my place I will give you enough of a piece to make a knife. From a piece I have had since the 70s when I made one knife from it. Enjoy

I assumed these were from a surface planer rather than a veneer mill.

Blades that small would be for a surface planer. Logs are turned on a spindle like a big lathe and that is how you get veneer at least thats how they do it at the veneer mill down the road from me. I have boxes full of planer blades from the hardwood flooring plant in town that i do not use because they destroy belts discs whatever you try and grind them with.

Bob

Although I may lack the experience and skill to make a proper knife of this steel,
I do posses enough information to screw it up. So be it, scrap I shall make!

By the way Steve, sorry for yelling I was raised in a suburb of N.Y.