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Old November 1st 03, 05:27 PM
Ted Edwards
 
Posts: n/a
Default Info on how to make a chipper knife

Roy wrote:

Being that one of my knives on my chipper broke and I am a cheap son
of a bi%#@ i need to make one. Its approximately 1.25" x 3.75" x .250"
thick, with two 5/16" countersunk holes in it and a bevel of 37 deg
ground on one long edge.


I like the idea of milling a step and brazing in some carbide........


I don't like the carbide idea as carbides are brittle and chip easily.

I too am a cheap SOB


Not as cheap as me! ;-)

I would try the following: Cut the blade out of a piece of old (free)
leaf spring (plasma or O/A). Anneal, flatten, drill the holes and
roughly shape the edge. Build up the edge with Stellite #6 (TIG or
O/A). Grind the edge to finished shape and sharpen. You can then
harden and temper to purple for additional strength if you wish. The
heat won't affect the Stellite. You may have to sharpen it once after
some use as the Stellite work hardens.

BTW, I picked up a box of Stellite #6 TIG rods at a blow out sale at the
local welding shop. Stuff is expensive but that knife wouldn't take
even half a rod. I've made center punches for hot work out of tipped
re-bar scrap and even used it for some heat resistant electrical
contacts. Well worth having a few rods around.

I loaned a friend a cold chisel I made from a piece of 1" re-bar. I
forged it to shape with a very blunt square edge. I built up a bead of
#6 Stellite on the edge and ground to shape and sharpness. He wanted it
to clean off lumps of concrete left from knot holes in the forms. I
fully expected it to come back in pretty bad shape but I was curious to
see what would happen. Well, I found out! The edge was a little dulled
- not worth bothering to sharpen yet. No chips.

Ted