Removing pitting question *LINK*

Close up pic  *LINK*

Jonathan Peck -N.Y.

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A tip for the tip

Jonathan Ronnow, Sweden

>If you first grind back the bevel making it thicker at the tip, "dull it", you have far less chance to burn it. If its sharp its also thin, which will make it heat up much faster.

That said, I dont think you are ruining it. Since the thinnest part heats up first, thats where you should feel for heat. If you can comfortably touch it, its probably safe. If you see any annealing colors youve gone too far.. Look at the corners of the edge.

Try resting the warm chisel back against some cold steel/iron surface(jointer bed, dp table, bs table) between grindings. The cold surface will absorb heat and cool the chisel much faster than air alone will. Good tip from Lee�s sharpening book....

Jr

forgot one thing...

Jonathan Ronnow, Sweden

>... I rescued a pitted chisel the other day. I hollow ground the back slightly to make it much faster to flatten. Kinda like a japanese chisel. No point in grinding deeper that the pits. I used the side of a gringing wheel, after coloring the blade with a felt tip marker. The same caution about heat has to be taken....

The beltsander as I experience it will leave a convex shape, I think its because the belt is flexible. Flattening that is easier after hollowing, since the blade rests at the edges when the middle is relieved.

It doesnt look pretty efterwards, but it speeds up the flattening a lot. If you dont grind too deep, the hollow will be easy to flatten out later on.

Re: Removing pitting question

Todd Hughes

>Keep a container of water next to the grinder and when the chisel gets to hot to hold dip it in it to cool it off and then continue to grind it.The temper of the tool is ruined by overheating and not by cooling it in water as long as it was not over heated. Of course on an laminated chisel you only have to worry about over heating the small amount of steel in the last inch or two at the edge as the rest is iron and is not tempered anyway.....Todd