Thread: Knifemaking - what material?

In a job in another life we used to make knives from power hacksaw blades. We used them primarily for cutting rubber mouldings. used to hold their edge pretty good as long as you didn't try and cut the steel bench top.
Fast to grind up.

hope this helps

bollie7

Thanks, Bollie. Only problem that I see is that the power hacksaw blades are fairly thin.

I tried to recycle some kitchen stainless steel knives but they were useless, hard to sharpen and will not hold an edge. Should have better luck with the above-mentioned materials.

I made a knife out of a power hacksaw blade about 25 years ago, it was/is a good knife, holds its edge well. I've still got it somewhere.
I think most of the newer blades are bi-metal, so probably not so good.

I made a plane blade out of a piece of brand new leaf spring a couple of years ago, it was a huge disappointment, it sharpened up nicely, but wouldnt hold it's edge for long. Ended up replacing it with one of Thumbsuckers D2 blades, much much better.
I know a guy who made a machete out of an old spring out of a wreck, back in the early '80's, it was successful from memory.

You can get 01 blade steel in small sections from Allsteel in Dandenong.
Shape it first, then harden/temper as required.
Peter

In a job in another life we used to make knives from power hacksaw blades. We used them primarily for cutting rubber mouldings.

Sounds awfully familiar. Yeah mine was a mill knife in a past life. Wrap a bit of hot, freshly extruded rubber around one end for a handle


All I can say is make friends with someone with a large power hacksaw. The blade will probably be thicker. Ideal for what bollie7 says, as in cutting rubber. Good for carpet too. Cant say I have tried it on wood.

Is there any way to identify a bi-metal blade, as these seem unsuitable to knife making?

Go for the planer blade, or the leaf spring the planer blade will require a lot more effot grinding wise but wil hold the edge a bit longer than the leaf spring

Originally Posted by Tiger

Is there any way to identify a bi-metal blade, as these seem unsuitable to knife making?

They usually have Bimetal printed on them .Some times you can see the joint between the blade back and the teeth
Big down side to HSS knife blades is they break easily is you put any sideways pressure on them.

Kev.

Is Precision Ground Flat Stock suitable for what you want to make,its made by Sanderson Brothers and Newbould,its "PITHO" alloy Tool Steel Oil Hardening Non-Distorting about 1 1/4" wide and around .060"/.080" thick.

Originally Posted by jatt

Sounds awfully familiar. Yeah mine was a mill knife in a past life. Wrap a bit of hot, freshly extruded rubber around one end for a handle

Nothing so flash for us, we had to make do with making a handle out of wood and blowing a couple of holes through the blade with a stick welder to put screws through.
The old power saw blades also make real good flat scrapers. I still have a couple I use regularly.

Originally Posted by jatt

All I can say is make friends with someone with a large power hacksaw. The blade will probably be thicker. Ideal for what bollie7 says, as in cutting rubber. Good for carpet too. Cant say I have tried it on wood.

Yeah I didn't think about the size in my other post. The ones we used were from a 24" saw.

bollie7

A thin hacksaw blade sounds best, just be carefull not to get it too hot when grinding to shape, otherwise you'll have to harden and re-temper again: difficult on thin blades.

Car leaf springs make excellent knives; however they are very thick, not sure if the work involved making a knife would be worth while.

I made a number of knives from leaf and coil springs 20 odd years ago, sold all but one. Also made spanners, wood chisels etc. Diff axles make excellent hammer heads and cold chisels also.

Leaf springs have just the right amount of carbon to make them ideal for knife making. When using leaf springs the trick is in running the colours through the blade after hardening. You can make it easy to sharpen, which doesn't hold an edge for long, or, hard to sharpen, which will hold an edge for a very long time and anywhere in between.

When hardening (quenching) never use straight water: leaf springs and the like will crack. Use either salt water or sump oil, then run the colours through the blade to get the correct temper.

get a hold of an old cold saw blade 300mm+ dia 2.5ish mm thick, and some cutting and grinding disks, patience and time..... rough out your shape with the cutting disks, clamp the blade to the edge of a bench to minimise chattering. try to include a bit of handle length into the shape of it if you can. Then mark a line about 10mm bach (not beethoven) from the leading edge and clamp the knife so the edge is just off the edge of the bench and grind the edge holding the disk as flat as you can, you'll go through a few disks...cool the blade now and then....grind until you are nearly at the 10mm line but not half way to the thickness of the blade and turn it over and do the same. Chuck it in battery acid overnight to thin it out a bit, rinse well ( it will be black ) and go grinding again. when you're happy with the finish and the angle of the primary edge, get a handle on it.....old comet 3 handles work well or wood or strip back some old hemp rope and wind the stings around and around till you get the right feel and then areldite it or fibreglass resin.....then get a good edge up on a diamond stone.....be patient you won't have to do it often....keep it oily.:2tsup

get a hold of an old cold saw blade 300mm+ dia 2.5ish mm thick, and some cutting and grinding disks, patience and time..... rough out your shape with the cutting disks, clamp the blade to the edge of a bench to minimise chattering. try to include a bit of handle length into the shape of it if you can. Then mark a line about 10mm bach (not beethoven) from the leading edge and clamp the knife so the edge is just off the edge of the bench and grind the edge holding the disk as flat as you can, you'll go through a few disks...cool the blade now and then....grind until you are nearly at the 10mm line but not half way to the thickness of the blade and turn it over and do the same. Chuck it in battery acid overnight to thin it out a bit, rinse well ( it will be black ) and go grinding again. when you're happy with the finish and the angle of the primary edge, get a handle on it.....old comet 3 handles work well or wood or strip back some old hemp rope and wind the stings around and around till you get the right feel and then areldite it or fibreglass resin.....then get a good edge up on a diamond stone.....be patient you won't have to do it often....keep it oily.:2tsup

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This is probably the best choice of all.It will produce a knife edge that you can shave with, although some what brittle.

Carbon steels such as spring steel will take a lot of work due to the thickness and will not necessarily give a good knife as compared to the above.

Large hacksaw blades are good. The bigs one can be 2.5-3.00mm thick and HSS, much the same as cold saw blades but in a much more manageable size and shape.

There are plenty of steel grades around that you can make a knife from. But most if not all will involve heat treating and some serious shaping.

I would go with the simple option of cold saw blades or hacksaw blades. Cheap, effective and you can make several out of one old saw blade