Reciprocating saw blade steel

[BillinOregon]

I am sitting here looking at the nice grain in a used DeWalt bi-metal saw blade and thinking it might make a dandy little knife blade. The thought would be to anneal to soft, grind and file a blade shape then try to quench and temper the thing. But of course not knowing what steel it is, this is likely a waste of time. Oh well.

 

[ohio ramrod]

I have made several knifes from them. The steel works nicely once annealed. I anneal mine by putting them in a bed of red hot coals in the wood stove, cover with more red hot coals and let the fire burn out over night. Remember to mark which side is which when you start to work it since most are "bi-metal". That is they have a harder alloy on the cutting edge and a softer alloy for the remainder of the blade.Once worked, reharden and temper.Almost all steels reach "critical temperature" when a magnet will no longer stick. :hmm:

 

[Grizzly Adams]

I have made knives from Bi-Metal blades, and they work pretty well. Only concern would be how far up the "hard" steel goes up on the blade.

 

[LRB]

What Mountain Dewd said. The hard sections are usually quite narrow, but should already have a good enough heat treat. I see little to no reason to anneal it. Just work within the limitations of the hard section.
Bill, unless you broke a piece, you are not looking at grain. You are looking at machine markings. Critical heat/temperature is not when a magnet stops sticking. When the magnet loses attraction, the steel is at 1414°. The steel needs another 60° to 65° to harden properly when quenched. Some steels even more, but none at much less. If you put acid on the bi-metal blade, you might see the joint. Even vinegar may allow you to see it. With todays bi-metal blades, the edge is usually a high cobalt steel. Tough even when annealed.

 

[BillinOregon]

Thanks fellas. I didn't even realize what "bimetal" meant.

 

[BillinOregon]

Guessing it is that diagonal shadow ...

 

[Obi-Wan Cannoli]

I have an old sunflower brand file that was made in India. Its' face is 14" long and tapers down to 1" at the tip, it also has a very generous rat tail tang, and I have no idea why I bought it. I could mail it to you free of charge, no strings attached to make a knife out of for yourself as long as you promise to post pictures of your progress on the forum. The offer is open to the first response I receive.

 

[LRB]

Put it in a vise with one corner well exposed, and see if you can break it from the main body with a hammer blow. There is a good chance that file is only case hardened. If so, it will bend rather than snap off.
Yep Bill. That's the weld joint.

 

[BillinOregon]

Obi-Wan, thank you for the offer, but I have a box of files and a few leaves of decent, identified knife steel on hand. I guess I just hate to throw out something that might have a use.

:youcrazy:

Wick, thanks for the advice, as always.

 

[hoochiepapa]

Brings back memories! I had a friend in Viet Nam that made a boot knife from a power hacksaw blade. He had apprenticed under Ron Lake before the military, and did a fantastic job.
We went downtown Saigon for a few beers, and as we were riding in a taxi, a native on the back of a motor scooter reached in the window to grab my friends boom box. My friend slit his wrist so fast I never saw him move. Blood flew everywhere, and lots of screaming from the taxi driver and the guy on the back of the scooter.

 

[Obi-Wan Cannoli]

well, that is one way to "get your point across" I suppose

 

[BillinOregon]

Mike, that must have been one very sharp blade!

 

[hoochiepapa]

Hi, Bill!
All I heard was a ripping sound and then the screaming started. They were called "cowboys" and would steal you blind. The "white mice" (police) wouldn't help you at all.

 

[mooman76]

I heard years ago that the big hacksaw blades used in shops make a fine fillet knife.

 

[omarick1948]

Year's ago they did! Today, you never know what you get for metal.

 

[hoochiepapa]

This was 1970.

 

[pondoro]

The pointy knife was recently made from a power hacksaw blade that my dad fished out of a scrap bin in 1970 or so. I suspect it is M1 or something close. It will not temper at low temperatures as it was developed to stay strong even when hot. It was a bear to shape and sharpen.

The other utensils are actually old.

I'd like to see some smaller knives made from modern recip blades, as they are plentiful.

 

[F.G. Ford]

Not fool proof, but if the steel rings like a bell, chances are you can do something with it.
If it is a dead "thunk" chances are it is lead or lead alloy. Aluminium, zink, nickel, or some other alloy.
I made a patch knife out of an ugly old ( really old ) butter knife.
UNBELIEVABLE edge! And really keeps it.
Who would have thought that a butter knife, would hold an edge.
And it rings like a bell.
Fred