Which blade steel can be hardened the MOST?

Folderguy said:
If the teeth are ground away, and the good steel is gone, what is left is the softer steel, right? So how deep into the blade does the good steel go? Does it stop immediately at the top edge of the teeth, or is there perhaps another 1/16" that is good?
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There would have to be some steel below the bottom of the teeth for it to be welded on as a single strip. Otherwise the mfg. would have to individually attach each tooth. If you're thinking of trying this yourself then don't try to mess with a bimetal blade. Get one described as "all hard" or " high speed steel" so you won't need to worry about it. A bimetal or welded edge blade would only be useful for making a santoku or sheepsfoot blade anyway.

I bought a box of 10 all hard M2 power hacksaw blades on eBay 4-5 years ago and ground a very crude Loveless-style blade from one. Talk about tough to grind! M2 at 64-65 hRC really eats through belts.

I used this knife to dress a deer a couple of years ago. The edge retention is amazing! I am careful not to stress the blade laterally, but you know it can't be TOO fragile or the blades would never survive. I imagine the machines that use blades this big aren't exactly used for dainty tasks!
 
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elkins45 said:
There would have to be some steel below the bottom of the teeth for it to be welded on as a single strip. Otherwise the mfg. would have to individually attach each tooth. If you're thinking of trying this yourself then don't try to mess with a bimetal blade. Get one described as "all hard" or " high speed steel" so you won't need to worry about it. A bimetal or welded edge blade would only be useful for making a santoku or sheepsfoot blade anyway.

I bought a box of 10 all hard M2 power hacksaw blades on eBay 4-5 years ago and ground a very crude Loveless-style blade from one. Talk about tough to grind! M2 at 64-65 hRC really eats through belts.

I used this knife to dress a deer a couple of years ago. The edge retention is amazing! I am careful not to stress the blade laterally, but you know it can't be TOO fragile or the blades would never survive. I imagine the machines that use blades this big aren't exactly used for dainty tasks!
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Very helpful info, thank you :thumbup:

Have you ever tried/considered using planer blades for this?
 
Does anybody have an online source for the power hacksaw blades that come in the .1" thickness, without having to order ten of them?
 
Folderguy said:
Very helpful info, thank you :thumbup:

Have you ever tried/considered using planer blades for this?
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I have never seen one outside of the planer. My guess would be that the dimensions aren't suitable for knife making? Besides, why not just start with traditional blade making stock? Planer blades are made from good tool steels, but they are probably only mid-50's in hardness.

The reason for using the power hacksaw blades is because they are already ground thin, are conveniently shaped and (most important) are so darned hard. I don't know that planer blades would meet any of these criteria.
 
elkins45 said:
I have never seen one outside of the planer. My guess would be that the dimensions aren't suitable for knife making? Besides, why not just start with traditional blade making stock? Planer blades are made from good tool steels, but they are probably only mid-50's in hardness.

The reason for using the power hacksaw blades is because they are already ground thin, are conveniently shaped and (most important) are so darned hard. I don't know that planer blades would meet any of these criteria.
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My understanding is that planer blades are very hard too, although I don't know how hard. They are probably a bit thicker, which would be alright by me. Actually, the thinness of most of the hacksaw blades is maybe too thin, which is why I asked about those with a .1" thickness.

Do you know the thickness of the hacksaw blade you made your knife from?
 
elkins45 said:
I bought a box of 10 all hard M2 power hacksaw blades on eBay 4-5 years ago and ground a very crude Loveless-style blade from one. Talk about tough to grind! M2 at 64-65 hRC really eats through belts.
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I'm guessing that diamond hones would be a good idea, maybe grind a V edge with diamond hones and then convex it with a belt sander for the final step.

Looking on Ebay - the thicker power hacksaw blades sure aren't cheap! There is 2 blades for $38 + shipping (from Aus, shipping listed as $40 to US), but it is 2.75-3.00mm thick (2.5mm = 0.1") and would work pretty well I would think. For .075" thick blades the price isn't as bad and they aren't as hard to find.

Is this M2?
"fully hardened molybdenum high speed steel"
 
It could be M2. It could also be M42 or a couple of others. There are several molybdenum based high speed steels, any of which would likely make good light use knives. M2 is sort of the standard alloy. The others will be made to do things M2 won't do, such as higher heat, easier formability, better toughness, etc.

The teeth on the saw blades I've seen are the same as or slightly deeper than the edge wire. Grinding off the teeth would remove all the good steel. The edge wire is electron beam or lazer beam welded to the backing steel before the teeth are cut. To know for sure, polish one of the blades to a 220 or 320 grit shine, then etch in acid of some sort. The line will be very clear.

For what its worth, edge wire is a molybdenum based high speed steel. It just happens to be one that welds ok, and can be cold drawn (like copper) through 4 dies without need for annealing.
 
If you can find Starrett Redstripe from an industrial supplier you might be able to pick up a blade for less. They are full hardness HSS.

The blades I bought are 21" Atkins Borg-Warner Silver Streak. They are 0.088" (2.23mm) thick. Thinner blades make better cutters.
 
elkins45 said:
If you can find Starrett Redstripe from an industrial supplier you might be able to pick up a blade for less. They are full hardness HSS.

The blades I bought are 21" Atkins Borg-Warner Silver Streak. They are 0.088" (2.23mm) thick. Thinner blades make better cutters.
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How are those 0.088 blades? Do they feel strong enough, or have you any concerns about putting more than slight pressure sideways on them? Would you recommend going thinner than 0.088?
 
I think it will do normal 'knife stuff' just fine, but I wouldn't try to twist it and split the pelvis on a big buck or something like that. I started making a second knife from the leftover section the first blade came from and I C-clamped it to the deck railing to rough shape it with a disk grinder. There is a slight cup to the top board and the blade snapped under the clamp when I put a lot of pressure on the overhanging blade to grind it. So if I went thinner it would only be for dedicated slicers or skinners.

I wouldn't recommend thinner for a general purpose knife...if would be a shame to put that much work into it only for it to snap off at the handle the first time you bear down on it.

Are you in the USA? I would be happy to send you one if you wanted to try your hand at grinding one. It's an interesting experience to make your own knives, and with the hacksaw blades you don't have to worry about getting them heat treated. They're plenty hard already!
 
I found a Starrett Red Stripe blade on Amazon, 18 inches X 1.25" wide X 0.062 inches thick, ordered it, including shipping for about $20.

Thus, I should be able to make two knives from it easily.

If nothing else, it will be a learning experience for me.

Thanks for all the advice!
 
elkins45 said:
I think it will do normal 'knife stuff' just fine, but I wouldn't try to twist it and split the pelvis on a big buck or something like that. I started making a second knife from the leftover section the first blade came from and I C-clamped it to the deck railing to rough shape it with a disk grinder. There is a slight cup to the top board and the blade snapped under the clamp when I put a lot of pressure on the overhanging blade to grind it. So if I went thinner it would only be for dedicated slicers or skinners.

I wouldn't recommend thinner for a general purpose knife...if would be a shame to put that much work into it only for it to snap off at the handle the first time you bear down on it.

Are you in the USA? I would be happy to send you one if you wanted to try your hand at grinding one. It's an interesting experience to make your own knives, and with the hacksaw blades you don't have to worry about getting them heat treated. They're plenty hard already!
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Thank you, sir!

Just now I read your last paragraph, but have already ordered a blade from Amazon. It should work out alright. Thanks for the offer, in any case :D And yes, I am in the US.

Years ago I made a knife from an old file. Wasn't that great, but it did work. Most of what I do to knives now lies in the area of modifications, also some improvements, convexing the edges, stuff like that. Although I have made a few sets of scales that turned out alright. One from buffalo horn, the other two sets from tortoise shell celluloid. All look alright/fine.

Hopefully, the blades I make from the hacksaw blade will do alright in the kitchen, and opening boxes etc... not planning on cranking some moose's antlers loose with it!! LOL
 
Here's some free advice: you won't be able to touch it with a normal drill bit. When you decided where the holes for your handle pins will go, get one of those cheap disk grinders and hog out a big hole in the general vicinity. Make it bigger than the pin so some of the epoxy can squish it's way through and bond one scale to the other.
 
Folderguy said:
Thank you, sir!

Just now I read your last paragraph, but have already ordered a blade from Amazon. It should work out alright. Thanks for the offer, in any case :D And yes, I am in the US.
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I think I was editing my post to add that offer while you were typing your post about buying a blade.

If you decide you're addicted but want a thicker blade for your next project just let me know.
 
elkins45 said:
Here's some free advice: you won't be able to touch it with a normal drill bit. When you decided where the holes for your handle pins will go, get one of those cheap disk grinders and hog out a big hole in the general vicinity. Make it bigger than the pin so some of the epoxy can squish it's way through and bond one scale to the other.
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I have a bunch of stuff for my dremel, including diamond cutting discs that might work alright. One way or the other, I'll figure out how to make holes.

Will a tungsten carbide bit work? Are there any drill bits that will work?
 
elkins45 said:
I think I was editing my post to add that offer while you were typing your post about buying a blade.

If you decide you're addicted but want a thicker blade for your next project just let me know.
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You betcha! Thank you sir!
 
The HSS blade I used for my knife is only 0.055" thick, and I put enough lateral pressure on it to dig through a 1x6 with the point. I was very careful though. This is also the only knife that I've done the paper cutting test and left the bottom half still sitting on the table. Fold a piece of paper in half lengthwise 2 times and stand it on a table, then cut it with the knife. It's a pretty good knife if it even makes the cut.

I think WC (tungsten carbide) bits will cut it, but haven't tried it myself. All my knives from these things are stick/hidden tang.
 
me2 said:
The HSS blade I used for my knife is only 0.055" thick, and I put enough lateral pressure on it to dig through a 1x6 with the point. I was very careful though. This is also the only knife that I've done the paper cutting test and left the bottom half still sitting on the table. Fold a piece of paper in half lengthwise 2 times and stand it on a table, then cut it with the knife. It's a pretty good knife if it even makes the cut.

I think WC (tungsten carbide) bits will cut it, but haven't tried it myself. All my knives from these things are stick/hidden tang.
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How long is the blade on yours?
 
hitachi's claims that HAP72 can get to 70 HRC, but i've never seen it used for a knife before.

cowry-x is very close to ZDP-189, both should be able to get in the 66-67HRC range.

i don't know how it will work, but if you are really set on hardness, try to find a company that makes tungsten carbide blades for industrial machining. buy a knife design you like and send them the blade to be used as a model. it will probably be very expensive.
 
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