[Greg C]

Thanks for the comments.

I used an angle grinder with a thin cutoff disk to cut out a rectangle piece about 1/2" X 3". Used a bench grinder to shape the blade. I put the initial bevel on the blade using a belt sander. Finished the blade using the scary sharp method stepping through grits from 320 to 2000. Polished on a leather strop.

Planning to start a smaller detail knife soon. I will try to take some pictures of the process. It turned out to be a lot easier than I thought it would be.

Greg

[mark yundt]

Making knives is fun,isn't it Greg? As you found out the industrial band saws is good steel for knives. I have also used circular saw blades ,from 7 1/4 up to 36" ones I found. Other sources include old jointer blades , even new ones from the box stores are fairly cheap for a set of 3. It's tool (A3) steel available in 1/8 th inch,,12" long. As well as just going to the local dollar store ( or rummaging through your old junk drawer or flea markets) for old high carbon kitchen/chef knives. I've made chisels out of old files as well. You really need to kill the temper to work them easily. As well as springs,,but I'm no metallurgist,,but I think the composition of the steel is a bit different than true tool steel.
In several cases I simply used a torch to cut out my blanks. I have also used cut off wheels in my angle grinders.
I am never concerned with taking the temper out of the steel simply because it's easier to work it and not worry about losing it,,if you take it out to start with. It's easy to re anneal and then temper a blade to whatever Rockwell hardness you want.Oil,water and brine solutions will quench at different speeds depending on your steel and harden it right up. Then it's merely a matter of tempering it to take out the brittleness.

Rudimentary hardness testers are quite simple to make. Many times you can also tell the quality of your tempering ( using a piece of scrap) by snapping the steel and seeing the grain structure,,,as well as watching the type of sparks that will fly off the steel when pressed to a grinding wheel. Each type of steel throws off specific sparks. For an example,,touch a hardened file to a wheel and then a piece of cold rolled steel.The variety of sparks can tell you quite a bit about the steel. And that's why cold rolled will never make a knife blade.
Use any source of steel that was originally tool steel and you should be just fine.

[Capt. Bandaid]

I would suggest orienting the blade cutouts parallel to the long axis of the bandsaw blade. The steel is rolled in this direction and will have a bit better strength and toughness if the edge is parallel to the rolling direction. Note that the band saw teeth run this direction.

[Greg C]

Capt.,

I hadn't considered this but it makes a lot of sense. The slight curve didn't seem to have any effect on the final outcome. On a small blade, such as a carving blade, this should be okay. If I were to try to make a longer blade, say 3" or longer the curve would be greater than the thickness so this would be a problem. I suppose I could try straighting a longer blade.

Greg

[Hi_Ho_Sliver]

Where are you getting industrial bandsaw blades? I still have a couple of straight razors left, and doubt anything is going to beat them for a great knife....but what the hay, will try anything once!

[Capt. Bandaid]

Greg, you may be right about the short carving blade. The concern is a bit esoteric. The structure of the steel resembles plywood. Loaded across the grain it is very strong and ductile; loaded parallel to the grain, as in a blade cut from the transverse direction, it is less strong and ductile. Again, I may be making a mountain out of a mole hill for the size of blade we are talking about.

[Greg C]

Hi Ho,

I noticed the piece of bandsaw blade in a metal scrap pile at work and snagged it. One mans trash is another mans treasure.

Capt.,

Appreciate the information. Is there a preferred method to try to straighten the blank before grinding it to shape? Since the bandsaw had to be flexible, was this accomplished by the make up of the steel, low carbon, or lack of hardness? This is the first time I have tried my hand a knife making. I am planning to make six carving blades, three with straight cutting edges and three with curved edges in various lengths. The three curved edges should prove to be a challenge to grind the bevel in the blade.

Greg

[Capt. Bandaid]

Greg, The normal way is to soften the blade by heating it to a dull red and covering it with ashes or vermiculite to allow it to slow cool. You can then hammer it straight and grind it agressively. You will also have to re-harden it. That will involve some trials to see how best to harden it. Heat a small piece to red, and let it air cool. Heat another piece to red and quench it in water. Heat a third piece to red and quench it in oil (vegetable oil is better than motor oil but both will work). Put the pieces in a vise and brush then with a file. A well hardened blade will not let the file bite in; it will just skate over the surface. Do this after you have shaped the blade but do not finish grinding it. Leave a bit of metal to grind off after hardening and tempering. This is because the blade will loose a bit of carbon at the surface from heating it and you will have a thin layer of soft metal on your blade. Finish grinding it and temper for 1/2 hour at 425F, let it air cool, then temper it again at 425F for 1/2 hr. Finish sharpening it a go make chips. Check out www.littleshavers.com for a more complete explanation.