how thin do I make the blade edge before sharpening?

ginshun

ginshun

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Apr 6, 2004
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I am making my first blade right now, just with drill, hack saw, files sand paper, etceteras. I am basically to the point where the blade just needs to be sanded down smooth, but I am not sure if I should thin the edge more or not.

Should I take it right down to where it is sharp, or should I leave it with a little bit of flat on the edge before I harden it?
 
Leave about 1/16 of an inch on the edge. If you have too little the edge can warp and crack. Also you need to remove the decarb from the edge so taking it thinner is a waste. If you water quench a steel you need a thicker edge than if you oil quench it; so the thickness you need will also depend on your quenching method.
 
I grind or sand to almost 0.08" to 0.1" edge thickness. If you sand down sharper you may face wrapping. I had a knife beyond recover as it was ground to 0 edge, after quench edge was wavy like a cloth...

Emre
 
You can learn it from your favorite knife.
Maybe you have some knives around you.
Better the sample and your building one belong to the same type of edge.
 
That thick eh? I only started with a 1/8" thick piece of steel. I might have it to thin already. I might have to take it back a little.
 
You haven't said what steel you are using....that is important.
The rule of thumb for carbon steels (1095,5160,O-1,etc.) is from .020 to .040 thick. For stainless blades about .005-.010 will be fine. If the entire blade is very thin,as in your
.125 max blade, don't make the final edge bevels until after the HT.
Good luck, and keep us posted.
Stacy
 
Befoer Sharpening or Heat Treating? Big difference!

Before HTing, I go to .040" +/-

Before sharpening, I take em down to almost sharp, .005 to .010"
 
Steel is 1095, and before heat treat is what I am wondering about.

Since I don't have a grider or anything, I'd just assume get as much done before I heat treat as possible, but I don't want to make it too thin and have it get all warpy either.
 
take it to about a Millimeter or .040-.050 American, Then harden, and temper, then do your clean up. then your final edge grind, :thumbup: post pics soon!:D
 
thanks guys.

Its at about .03 right now and ready for heat treat. Consensus seems that maybe I should take it back a little bit.

I will be sure to post pics after I heat treat and put the handle on.
 
Nah, no need to take it back any. Tim Lively (Tai Goo's Contemporary)regularly forges his edges down to about 1/32" .03125) and quenches from there you may want to normalize a few times first then quench to help avoid quenching stress fractures :thumbup: :D
 
cool.

And ya, I had planned on heating and cooling a few times before I quenched it. I had read a few other threads about 1095 and it seemed a common recommendation.

Heat treat is going to be done either in the fire pit or the old school wood stove in the garage.

Wish me luck.
 
ginshun said:
Steel is 1095, and before heat treat is what I am wondering about.

Since I don't have a grider or anything, I'd just assume get as much done before I heat treat as possible, but I don't want to make it too thin and have it get all warpy either.
Click to expand...

I use 1095 for my knives and I find it works well if you take the edge down so it's about the thickness of a dime. I've done the same thing and have taken the blade down too far. Just run over the edge with a file until it gets to the right thickness. Make sure when quenching you dip the blade point first and don't swish it side to side, but rather up and down is ok.
 
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