A couple of questions from a novice

AF

AF

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Jan 14, 2000
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I am making a knife from a lawnmower blade. Here's what I've done so far:

1. Cut the profile with dremel cut-off wheel.
2. Normalized the blank in one-brick forge.
3. Ground in the bevels using 4'' X 36'' belt sander.
4. Drilled the tang.
5. Annealed.
6. Reheated and quenched.
7. Tempered in toaster.
8. Sanded and sharpened.

No major problems so far. Here are my questions.

How is a belt sander different from a belt grinder?

Is annealing necessary as a preparatory treatment for the quench? In "$50 Knife Shop," Wayne Goddard says that this is the case for some but not all steels.

If the edge rolls and I decide to reharden, I don't have to anneal again? I think it was Buxton on the forums who advertised one of his knives as triple quenched...

All help and suggestions are greatly appreciated!
 
Well, here's a partial answer. A belt sander and belt grinder are really the same thing; I think of a belt sander as used for woodwork, a belt grinder a more industrial sort of tool -- but that's just symantics.

Annealing brings your steel to a "soft" state where you can work it. It sounds like you might be thinking of normalizing, but from here on you'll have to rely on more knowledgeable folks than I.
 
Tempered in toaster...now that sound dangerous! :eek: :D
Look forward to seeing the fruits of all this hard work :)
 
normalizing refines the grain in the steel after forgeing and help relieves stress from forgeing and grinding, annealing softens the steel before grinding, this helps you save on sanding belts and manual labor. When I forge a blade I normalize it 3 Xs, then anneal, if I do a blade by metal removal, I anneal then grind then normalize the blade 1 X before quenching, this helps relieve stress and helps keep the blade from warping during quenching.
If I have to reharden a blade I normalize 1X then heat and quench. We all have are own techniques, this works for me.

Hope this helps
Bill
 
Thanks for the replies!

I'd still like to hear more on the differences between a belt sander and belt grinder.

Bill, if you normalize before you reharden, what do you mean when you say your knives are triple quenched? Are they triple normalized? I'm confused.

Ferret, tempering in the toaster is a little smelly, but not dangerous I don't think. Unfortunately, I don't have a digital camera.
 
I'm having trouble determing whether the blade is hard. Using a butcher's steel, I tried to see if the edge would deflect under pressure and spring back. I couldn't tell. Then I held the edge upwards and hit it with the steel causing it to dent. I produced the same results with a swiss army knife. Tried running a file across the blade and tang to try and hear the difference. Nope, I can't really tell.
 
In order for me to reharden, the knife has to fail the brass rod test, which means when you drag the edge of the knife at about a 60 degree angle across the brass rod the edge rolls over and stays rolled over, that means it was drawn at to high of a heat and softened to much after hardening. So now I would normalize, then reheat and quench. if when triple quenching, after quenching, if a file takes a bite on the blade that means it hasn't hardened, so reheat and quench again, let air cool to the touch and check with a file, if the file slides down the cutting edge without taking a bite the edge is hardened, now reheat to ctitical and quench again, do this 3 Xs.From here it go's into the tempering oven, temper 3Xs, some say 3- 1/2hour peroids, some say 3 -1hour peroids, I temper mine 3 - 2hour peroids letting the blade cool to the touch between peroids.We all have our own techinques and different ideas about what we are doing, others might not agree with my style, but it works for me.
Hope this helps clear up a few things. ;)

Bill
 
Always thought, sanding is what you did to wood or plastic using abrasive sheets, disks or belts.

Grinding was what you did to metal with abrasive wheels, disks, or belts.

Somehow, sanding metal, has never seemed the right term but I guess it doesn't matter if the right finish shows up in the end!
 
Bills about covered it,I don't think there is much that i can add.
If the file doesn't slip after you hardened it and before tempering then you need to re-quench it..If it is to soft after tempering then re-harden and draw back at a lower temp.
Bruce
 
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