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View Full Version : KNIFE Question: What is the best way to cut the tip on a finished blade...???



Sourdough
09-05-2010, 06:28 PM
So as to do the least amount of damage to the temper, what would be the best way to remove 3/" to 1" from the tip of a finished "New" knife blade. I have an abrasive cut-off saw, I could give it a very quick groove then cool it and try to break it off. Or I can grind it a little at a time to keep the heat down. Or open to ideas. I have a 4" beltsander also, The steel is 1095 and Rockwell is 57-58

http://www.chestnutridgeknifeshop.com/catalog/product_info.php?cPath=72&products_id=630

panch0
09-05-2010, 06:31 PM
Make sure you use a fresh belt on the grinder. Make a pass or two then dip and swirl around in the water. It will take a while, but you will save the temper. If it is too hot to touch cool it off quickly. If it turns blue or broun there could be damage to the temper.

Sourdough
09-05-2010, 06:34 PM
Thanks, Frank

p moore
09-07-2010, 01:21 PM
Your fingers will tell you when you need to cool the blade. If you smell hide cooking, quench the blade. :innocent:

Paul

canid
09-07-2010, 10:47 PM
Your fingers will tell you when you need to cool the blade. If you smell hide cooking, quench the blade. :innocent:

Paul

that's it right there. if you keep your finger backing the immediate area being ground, you'll know it's getting too hot well before it's a problem. for most blade materials, the point at which the structure starts changing is when you approach 400f.

you can really see it when the color begins to change, but this is the point when the damage has begun. just let your finger be your thermometer, and be ready to move quickly, because grinding with a worn abrasive, and with some steels, the temperature can climb from uncomfortable to the tough to 300f or more pretty quickly.

if you do notice only a little color change, you'll see that it starts where the steel is thinner [the very tip and the blade edge]. if this area is tiny, it will be temporary, as successive sharpenings will eventually grind back down to harder steel.

unless it's a carving knife, i like to have the tip a bit softer than the edge of the blade anywya, so that if damaged it will ding/bend rather than chip.

Sourdough
09-08-2010, 12:02 AM
I just have never been a fan of sharp points on any knife, I just never stab anything. And for me a sharp point can nick the cape when caping or fleshing. I like about a 1/4" to 3/8" Radius on the tip.

Alaskan Survivalist
09-08-2010, 12:56 AM
I would use a dremel with a cutoff wheel. It would take patience and many passes but could be done so as not to affect temper.

Rick
09-08-2010, 06:58 AM
If the point is the problem, can you just use a hand file and dull it or round the tip off?

kyratshooter
09-08-2010, 01:56 PM
In my experience, you are not going to be able to snap off 1095 at the 1/4" thick level with just a slight guide groove.

I would use the abrasive wheel, touch and dip, touch and dip. then smooth it with the grinder and sander.

Like the others have said, keep your fingers right against the area you are working. When it is uncomfortable you are at the point of drawing temper.

The normal point of discomfort is 160 degrees against human skin. Above that one can not tolerate long term comtact.

I really think it is great that when you buy a big knife to look at from Becker they give you a small one to actually use.

Camp10
09-11-2010, 09:00 PM
So, did you cut it off?

Sourdough
09-11-2010, 09:30 PM
So, did you cut it off?

Have not received it as yet.

Camp10
09-11-2010, 09:46 PM
Keep in mind that when you cut it you will have to reshape the new point so that you will be able to sharpen it. It will be quite thick where the two edges come together and you need to cut this down in order to form the new edge.

As far as over heating it, others have covered this pretty well so far. 1095 with an Rc of 57-58 was tempered (or would be if I did it) at 425-450° so you have a little bit to work with. Use a light touch with your sander, a new belt around 60 grit (then clean it up with a 220)and dip it in water between each pass.