What kind of knife would you make from a 24" power hacksaw blade?

T. Erdelyi · Apr 20, 2003

I bought a 26" power hacksaw blade for 25 cents at a yardsale, the markings on it indicate Sandflex HSS BI-METAL MM 650-50-2,50 IN 26-2-.100 6 KA

I take it to mean that it's 26" long, 2" wide by .100 thick, which is good because those were the dimensions I came up with when I measured.

It also says SANDVIK SWEDEN on it.

Now my question is, what kind of steel is this, and what kind of knife would you make? Small Machete, Fillet knife, Chefs knife?

Also would I be better off slow grind to shape or take the temper out shape the blade and than reheat treat?

Also are these blades differentially tempered, is the back of the blade softer than the cutting edge, or is it uniform?

Is this even something I can do with out an oven for heat treating?

Help me guys, this is a nice piece of steel, it's gotta be good for something.

John Andrews · Apr 21, 2003

T, I made some decent knives using the yellow painted Sterrat power hacksaw blades, thickness .088 and .100 . They were not the bi-metal, but I did make a couple of large kitchen knives using the bi-metal blades. I don't know what brand they were, but they were factory painted gray. I used the tooth side for the cutting edge, and they made really good knives. I didn't polish the kitchen blades, but put a mirror polish on the others using diamond compound from the tube, and polished with homemade 3/4" dia., 1/4' thickness hard feld pads cut from ink pads and then hot glued onto a Dremel brush. The homemade small buffer wheel I used in my tabletop drillpress. Worked great! Really put an absolute mirror polish on the damn hard blades. The first knives I sold were made from this stuff, and brought good money, and the customers are still happy with them.P.S.. the pads are used flat side down, and you polish a circle with not too much pressure, then move the blade over about half a circle or little more, and repeat. Then do a light move around polish. Add just a little oil to make your diamond compound stretch further, otherwise you will use a lot more compound. And be sure to have some paper taped onto your drill press table, or the underneath side will get scratched up while you are polishing the other side.

T. Erdelyi · Apr 21, 2003

John what did you profile the blade with?

Also, did you have to heat treat the blade?

I see alot of these saw blades, around here,(I'm not to far from what used to be Bethlehem Steel) and they're usually pretty cheap,(under $2), so if they make a nice source of blade steel. I think we'll buy a few more.

R. Lemmen · Apr 22, 2003

OK, I am not the most qualified to give a response but here goes...

Bi-Metal hacksaw blades are just that, two pieces of metal that have been welded together. The HSS tells me that there is a strip of High Speed Steel (usually 1/4 to 1/2 the width of the blade) used for the teeth. Most likely just the tips of the teeth are hardened. I dont know what the backing steel would be but it is supposed to be more springy/elastic than the HSS.

Hopefully this helps some.

Cheers,

John Andrews · Apr 22, 2003

T, From what I found out, you can't "soften" the blades because of their makeup, and what I did with the bi-metal blades was grind the profile on a grinding wheel after using Dremel cut off wheels for rough cutoff. I also heard the tooth portion was the hardened part, so this is why I used the tooth portion for the cutting edge. The upward sweep to the point holds and edge just as good as the tooth part, so I would suggest profiling your blades the same. One of the knives I made for our HQ at work, as a test blade. It is the only knife that stays sharp! It is about a 6" utility kitchen blade that is used to cut food on regular plates, which as we know, really normally dulls an edge pretty quick.That knife is the first one grabbed for serious work at our weekend feeds. Now, they want a set, and our fire dept. wants a couple, also. I just put a maple handle on it and coated the handle a few times with poly, which has held up very well, too.

Reg ELLERY · Apr 22, 2003

If you intend forging in the future. They make a good componant for your first damascus blades. The 1 inch wide even better easier to forge if you are still learning.

I have even used 3 ordinary hack saw blades then 1 layer of 1/8 mild steel flat bar same width and so on until about 1/2 inch thick, nice contrast. good fun for the beginner.

T. Erdelyi · Apr 22, 2003

I was talking with someone else who suggested making a Wharncliff blade, I think that might be the route to go, also anyone have any idea of how far up the HSS goes on a bimetal?

I do have a forge, the old kind that looks like a heavy duty grill with tall sides, I working on getting a blower motor for it.

Thanks for the info I'll let you know how I make out.

John Andrews · Apr 23, 2003

T, you have anyone in your neighborhood that has a Rockwell tester? Just an idea, if you want to check the blade for hardness beyond the tooth range. That is, if you are going to do stock removal for the blade. I like the idea of forging with some mild steel and the hacksaw blade combined,too. Pretty cool!The large kitchen blade I made for my fellow officers seems to have pretty hard steel beyond the tooth range, because it also seems to hold an edge really good. What I am referring to is the upswept part to the blade point.

Sweany · Apr 23, 2003

clean the hacksaw blade and etch it. That should show the weld line. Ferric chloride from radio shack. Vinegar might work to show the line.