question for Yvsa and the other steel men.

F

fausto nasafiaschi

Joined
Aug 6, 2000
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506
Would you guys consider to use the blade of a reciprocating saw (the big ones used in workshops to cut steel stock and piping, about 3 mm thickness)to make a knife out of it?. If yes, once the blade is ground to the desired profile, would you do consider to experiment any heat treatment? Also do you have any advise as to how to grind it (speed, abrasives).
Next year I will be spending several months in a Shipyard and I would like to make my self a small fixed blade 3 1/2" for every day carry. I've seen some ugly ones (usually handled with duct tape)and they cut like razors.
Over there expensive knives have a tendency to walk away from their legitimate owners.
Fausto
 
Does it say "high speed steel" on it? I'm not sure what that's called in Italian; might not be a literal translation.... If it's high speed steel it's not heat-treatable and although it's very hard it's pretty brittle. It'll hold its edge very well and it won't break if you're always careful not to pry with it or do anything at all abusive, but if you have a choice I suggest avoiding high speed steel for most purposes.

If it doesn't say high speed steel or whatever the Italian term for that group of alloys is, it'll probably work very well. Temper it by heating to 400 degrees Fahrenheit in an oven (what's that in Celsius??? It's too late at night here in Remulak to do arithmetic (I have other excuses I use at other times -- too early in the morning, too soon after dinner, etc.)) Degrease first or the oil on it will smoke and your wife will kill you. If it's painted remove the paint for the same reason. Temper it before you grind it; it'll be easier to work. Be careful not to overheat it if you use a power grinder.

Another way is to anneal it so it's really soft, grind it into a knife, then harden and temper when you're done -- but if you're going to go that route you might as well buy steel stock instead of using an old power hacksaw blade; then you'll know exactly what kind of steel you have and how to heat-treat it. You probably don't have any way to heat it red-hot to harden it, though; you can't do that in an oven. If you do decide to do it that way have a look at the Shop Talk forum at this website; some of the best knifemakers in the world hang out there and they'll tell you everything they know; they're a great bunch of guys.

If you don't mind taking your time about grinding it and being careful not to overheat it, an old power hacksaw blade can make a very good knife. I've made several myself.
 
Thanks for input Cougar,
Yes, most of the blades I've seen are marked HSS (in italian "acciao rapido"). The knife would be meant just for cutting jobs(small ropes, rockwool panels, open boxes...)and prying would not be considered in the options. I will have a look at the Shop Talk Forum.
Fausto
 
Thanks for good help, Cougar. And, Fausto, if there's any doubt buy some steel stock of your choice. It's not that expensive and better to be sure than waste a lot of time and effort and end up with something you don't want.
 
Hi Fausto!
I've made knives out of old power hacksaw blades before, and they work well. The problem is that they are harder than woodpecker lips and will eat up your abrasives pretty quick. When doing stock removal I generally start with a 60 or 80 grit belt (I don't know how our grit measuring system compares to european system); this will take of metal and fingertips real quick. I finish with a 220 grit belt and hand sand with progressively finer grits until I have the finish I want. I'm with Cougar on this one though; get yourself a piece of oil hardening tool steel from the guys in the ship or shipyard's machine shop and start from scratch. It is much easier to grind and finish the blade, and you'll know exactly what it is made from. There are alot of heattreating threads on the knife maker and bladesmith forums, especially for 01 toolsteel and 5160. P.S. don't use hacksaw blades marked "Bimetal". They are medium carbon steel with a highspeed steel edge welded on them. Good luck, have fun, be careful! steve miller
 
Fausto if I hadn't of listened way back when I would have been carrying a talonite knife for some 35 years now, but the people I asked, more experienced machinists, said it was too brittle and would never make a good knife.

Since it seems to be HHS you just have to take a bit more
care.
As Steve said it will eat belts faster, but who cares.:D
The main thing is to grind the knife out without burning the steel. If it goes past a straw color you have gotten it too
hot!!!!!
Keep a large container of water nearby and dunk the steel when it begins to feel warm, depends on how hard hard you push and how sharp the belts are as to the amount of dunking the steel
gets.
Finish the knife blade as you want it and then put it in a toaster oven on about 375*. Put the knife in for an hour. If it has turned straw color, perfect!!!!!!! If it hasn't put it back in at 400* for an hour and if necessary keep puttting it in for an hour at 25* intervals until you get the desired straw color.
There are degrees of straw color ranging from a light dead grass straw to a dark straw color. The darker the straw the softer it has became, not necessarily a bad thing.
When I got it to the straw color I wanted it I would go for a multiple draw and put the knife back in after 24 hours twice more for a total of three times.
That may accidently help to toughen the HSS up a bit, may not make any difference at all, but it takes no effort so why not? ;-)

Getting holes in the tang for pins if you want them will be the most difficult thing to do.
Like Steve I have made a few knives outta the power hacksaw blades. Drilling holes in them aren't woth the effort. Just rough sand the tang area and put slabs on using a good epoxy and you're good to go!!!!
Good Luck and let us see pix of the finished deal okay?:)
 
Fausto,
If you are in a shipyard, there will be torches and welding equipment and probably all you need. For a basic knife of band saw, hack saw, or other thin material that may hold an edge, this is what I used to do and it works pretty good. The heavy banding material (1 1/2" to 2" wide) is what I made my mother a paring knife out of in 1964 and it is supposed to be 1095 steel. (She has almost wore it out)
1st. Grind the blade to the shape you want.
2nd. Have a friend or some one to burn, cut, or melt, the holes where you want the pins to go that hold the handle on.
3rd. Drill your holes in the handle through the holes you made in the blades handle after you have smoothed out the handle again.
4th. Attach the handles with pins and epoxy, the epoxy will fill the space in the holes and it will never move. You could also pien the pins a little if you use it real rough.
5th. Make a sheath and sharpen.

A pouch type sheath works good on knives that don't have a guard or finger notch. If you contour the handle to fit your hand, you just made a custom :). Welcome to the world of bladesmithing.
 
Although annealed steel stock isn't very expensive, even if you have a way to harden it or could get somebody to do it for you -- hey, money isn't everything. The whole consumer-society philosophy of throwing things away and getting new isn't just wasteful of money -- it's wasteful of the environment; it isn't a sustainable lifestyle. Making knives out of scrounged scrap steel is socially responsible! (It's also fun.)

If you'll be at a shipyard you'll probably have a wide choice of steel, but power hacksaw blades are great for small knives like you're talking about. I might have exaggerated the brittleness of high speed steel; some people like it. I made several blades out of it, was impressed with the edge-holding, but I broke one of them and then I decided to use tempered tool steel hacksaw blades in the future. It's a matter of personal preference and what you're going to use it for and how you like to use your knives ... I don't care that much about extreme edge-holding and I'd rather not have to be at all careful with a knife. A tool steel power hacksaw blade, even after tempering, will hold its edge very well, better than most knives you can buy (especially those you can buy at a reasonable cost).

It's occurred to me it just might be more cost-effective for HI to buy 5160 stock than to pay somebody to run around scrounging old springs -- but don't tell Bill I said that. Even if it would be cheaper it wouldn't be as socially responsible.
 
Welcome to the Cantina. I've been bragging you up in here.;)

Bro, et al, in case you didn't put it together this is *The* Ray Kirk of Raker Knives. The Bro who makes those wonderful Wirk Knives!!!!!
And the one who I got my prized little 5" Hunter from!!!!

Really good to see you here Ray!!!!!!:)
 
I figured out who Ray was -- is -- and he's most welcome here in the Cantina. I, along with many other non-experts, can use all the professional help we can get.
 
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