Thinniing A Head Knife Blade

[goertzen77]

I BOUGHT AN OLD C.S OSBORNE ROUND KNIFE MADE IN NEWARK NJ . I WAS TOLD THOSE KNIVES ARE MADE OUT OF A BETTER QUALITY STEEL THAN THE NEW ONES. THIS KNIFE BLADE IS ALOT THICKER THAN THE NEW CS OSBORNE ROUND KNIFE AND I WOULD LIKE THIN BACK THE CUTTING EDGE SO I WOULD LIKE TO KNOW HOW TO DO THIS PROPERLY WITHOUT LOOSING ITS TEMPER. THE STEEL ON THIS KNIFE SEEMS TO BE ALOT HARDER THAN THE NEW ONES AND ALSO ALOT HARDER TO SHARPEN.I WOULD ALSO LIKE TO KNOW HOW FAR BACK TO THIN THE BLADE?? THANKS

Edited July 9, 2010 by goertzen77

[dirtclod]

I have used a table mounted belt sander a couple of times to thin a blade down. When do it start with a 150 grit belt and go down to a 400 then buff it. So far i haven't had any problems loseing temper. main thing is take slow and don't get the blade to hot. That's the way i did mine but if you do yours do it at your own risk because i'm not a knife maker. I may of just got lucky.

John

[bruce johnson]

I have had the best luck with thinning them down with wet/dry on a small wood block and laying the blade flat on a bench. I just follow the arc of the blade around. I did that on the last few and it worked the best for me. Going down through the grits made it go fairly fast and then I did the final edge work with a slack belt 1" belt sander that was mentioned a while back. I am going back through some other knives and redoing them this way too to thin a little more and get the final edge.

[JLSleather]

Depends on how precise you want it done, actually. Got a machine shop close to you? Ask 'em to stick it in a lathe with a tool-post grinder. Probably run about $30-$50 around here, but you'll have a precision edge like ... oh .... forever. Find a guy who knows what he's doing and you'll only lose about 1/64" on the radius of the blade.

[Tannin]

I invested in a small, cheap old American WEN Wet Wheel off ebay some years ago - it has proven invaluable. Cost just over half the price of a mediocre Japanese wetstone. I don't think they make them any more - which is a shame - but happily there are quite a lot of used ones around. I use it mainly to (re-)establish a sharp edge on very blunt tools & knives - free-hand. Then I move onto stones - I have several options but currently favour oil stones (simple, inexpensive & effective).

Something like this:

Edited August 29, 2014 by Tannin