Author Topic: knife grinding question  (Read 22949 times)

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Offline osage outlaw

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knife grinding question
« on: August 01, 2015, 10:38:26 pm »
I'm trying to finish up this knife I started a few months ago.  I made a simple grinding jig and got one side looking good.  I can't figure out how to get the other side.  Do I need to bolt a block of wood to the table to get the blade above the wheel gard?





I started out with nothin' and I still got most of it left

Offline JoJoDapyro

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Re: knife grinding question
« Reply #1 on: August 01, 2015, 10:45:28 pm »
We took a dremel to tykes sander to get the edge. We ran into the same issue.
If you always do what you always did you'll always get what you always got.
27 inch draw, right handed. Bow building and Knapping.

Offline Pat B

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Re: knife grinding question
« Reply #2 on: August 01, 2015, 10:58:10 pm »
Clint, what grit belt is that?
Make the most of all that comes and the least of all that goes!    Pat Brennan  Brevard, NC

Offline Loope

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Re: knife grinding question
« Reply #3 on: August 01, 2015, 10:58:25 pm »
Flip your jig over to put the "top" side of the jig down on the table and then grind the knife with blade edge facing down.  Or... grind freehand.  I'm no expert, but have ground all mine by hand with no support... hard to get a flat edge, I wind up with more of a convex edge.

Michael

Offline osage outlaw

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Re: knife grinding question
« Reply #4 on: August 01, 2015, 11:43:57 pm »
Pat, I'm not sure what grit it is.  It's the belt that was left on there from when I used it on a bow.  I can check it tomorrow.

Loope, I tried that and the grind was to much toward the edge.  I would screw it up if I tried to do it free hand.
I started out with nothin' and I still got most of it left

Offline JoJoDapyro

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Re: knife grinding question
« Reply #5 on: August 01, 2015, 11:47:03 pm »
Duh on my part. Clamp your knife a bit higher on the wood. I was using a piece of angle and vice grips. I see the issue now.
If you always do what you always did you'll always get what you always got.
27 inch draw, right handed. Bow building and Knapping.

Offline E. Jensen

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Re: knife grinding question
« Reply #6 on: August 02, 2015, 12:32:16 am »
Just learn freehand.  Its not that hard.  You won't regret it.

Offline KHalverson

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Re: knife grinding question
« Reply #7 on: August 02, 2015, 09:51:43 am »
Just learn freehand.  Its not that hard.  You won't regret it.


x2
go slow and check often.

Offline osage outlaw

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Re: knife grinding question
« Reply #8 on: August 02, 2015, 10:45:42 am »
I'll give free hand a try on the next one. 
I started out with nothin' and I still got most of it left

Offline E. Jensen

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Re: knife grinding question
« Reply #9 on: August 02, 2015, 10:47:57 am »
Also a lot tougher to burn your edge with bare hands.  Still can happen in the blink of an eye, but you have one more sense to detect and prevent.

Offline burchett.donald

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Re: knife grinding question
« Reply #10 on: August 02, 2015, 11:18:44 am »
   Clint,
           I do both ways...Jig and free hand on some applications...The jig will give you a true flat grind...With your set up you could use a very square block or object to get yourself above the wheel guard so you can reverse everything...Heavy grit will reduce heat some also...Was the file annealed?
                                                                                                                                           Don
Genesis 27:3 Now therefore take, I pray thee, thy weapons, thy quiver and thy bow, and go out to the field, and take me some venison;

Offline osage outlaw

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Re: knife grinding question
« Reply #11 on: August 02, 2015, 12:00:21 pm »
The file was annealed.  I free handed the other side this morning.  It turned out better than I thought it would.  How fine do you get the edge before hardening and tempering the blade?  I'd like to get this one ready for scales today.

E. Jensen, I got just a small discolored spot on the blade from grinding it.  It wasn't burnt, just a slight discoloration.  Will that ruin the edge?
I started out with nothin' and I still got most of it left

Offline E. Jensen

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Re: knife grinding question
« Reply #12 on: August 02, 2015, 12:12:30 pm »
Anything more than straw color is ruined, if its after heat treatment.  Before it is negligable

Offline burchett.donald

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Re: knife grinding question
« Reply #13 on: August 02, 2015, 01:09:41 pm »
  Clint like Jenson said, you don't want to get it hot after heat treatment or tempering...It's a matter of preference for some but I will take it almost finished before heat treating...That way all I have is some light work to remove. The knife in the pic is just out of 1900 degree kiln, heat treated and very close to finished as far as stock removal goes...The edge is almost ready for a stone at this point...Like I said matter of preference...
                                                                                                                                               Don
Genesis 27:3 Now therefore take, I pray thee, thy weapons, thy quiver and thy bow, and go out to the field, and take me some venison;

Offline osage outlaw

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Re: knife grinding question
« Reply #14 on: August 02, 2015, 01:34:34 pm »
Thanks for the help guys.  I haven't heat treated it yet.  I've been reading about normalizing the metal.  It said to bring it up to a non magnetic temperature and then let it cool off to room temperature 3 times before quenching it in oil.  Does that sound about right?  I have a toaster oven to temper it in.
I started out with nothin' and I still got most of it left