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View Full Version : Fabrication and Shop Techniques Making a pairing chisel from a planer knife



Cody Cantrell
10-08-2012, 2:09 PM
I read a post the other day that mentioned How they made pairing chisels out of planer blades at Williamsburg. This got me thinking... I have some 18" planer knives that are trashed but could still be useful so I kept them. They are high speed steel, which is very brittle, I would like to anneal the tang but the annealing process is seems very drawn out and I wouldnt be able to do just the tang. My plan is to heat the tang to cherry red and then slowly cool it in a bucket of wood ashes overnight. Is there a problem with this or any dangers involved? Thanks for any help.

Cody

Mel Fulks
10-08-2012, 2:34 PM
True high speed steel was often used just a few years back for home made chisels. Most of the steel now is NOT high speed . The real stuff is a darker greyer color not a whiter silvery color. If is unmarked it may or may not be high speed.I don't know if you can change it with heat or not ,the hardness HS comes mainly from the alloy. If it is not real HS it WILL NOT make a good chisel.

Cody Cantrell
10-08-2012, 2:36 PM
This does not through many sparks when ground, the blades came from a high school and the tube they were in is marked 1983.

Mel Fulks
10-08-2012, 5:02 PM
IMO the easiest way to test it is hone up old cutting edge , wrap a rag around the ends and use it like a draw knife.If you are satisfied with the surface it leaves and it cuts smoothly rather than haltingly ,then you will be happy with it as a chisel. Even if you don't think it's good,you need some inferior tools for dealing with paint and nails.

George Carlson
10-08-2012, 10:55 PM
This does not through many sparks when ground, the blades came from a high school and the tube they were in is marked 1983.

Were you grinding the cutting edge, or the back of the blade? I had a planer that used carbide or stellite brazed into the front edge of a mild steel blade. The edge was hard hard, but the body of the blades was fairly soft. The joint between the two metals was invisable until the blades became old enough for the surface of the two metal to change slightly in color. At Williamsburg, were those planer blades, or plane blades (big difference). I wouldn't think they would use a planer at Williamsburg?

Cody Cantrell
10-10-2012, 1:33 PM
I ground the end of the blade. It was definitely planer blades, it does sound weird for Williamsburg.