All About Pocket Knives

If you had to narrow it down to JUST ONE blade material, what would you consider the best to go with? Also, has...or does anyone make a blade of titanium? And if not....why?

Dewman

I know Mission makes some Titanium knives, particularly for diving and work with explosives. They are sort of expensive, but seem to serve a purpose. I have also seen a couple of Titanium credit card knives as well.

All around, inexpensive, go to steel for me, assuming proper heat treating, is probably 440C.

Bill

EDITED

Hey Dewman,


What is your intended use of the knife or blade? That's normally a factor when choosing a material.

Gary

gmusic wrote:Hey Dewman,


What is your intended use of the knife or blade? That's normally a factor when choosing a material.

Gary

....just a general question seeking the thoughts and preferences of the "experts".

Titanium does not make a good blade material except for dive knives. Titanium has a natural oxide layer that developes when exposed to the oxygen in air (Ti02), about 1/2 to 1 micron thick (.0000005 to .000001 of a meter thick). It can only be hardened up to about 46 to 48 Rc, but in it's natural state makes a good backspring as is. The oxide layer is what makes titanium corrosion resistant, so it is good for saltwater use. Some titanium dive knives are available for as little as $60 (don't know the alloy) at my local dive shop, useless for a knifemaker to compete with.

There is one company that sells Timascus. http://www.alphaknifesupply.com This is a titanium that they've developed titanium into a damascus material, they are the sole source of this. I don't know how they do this because the oxide layer would have to be etched off. Seems like they still use it for handles, rather than blades.

Titanium must be mig or tig welded, silver solder, oxy acetylene, or glue will not hold, that's why knives with titanium liners always have the scales held in place by screws. Titanium is a specialty material, expensive for what knife maker use, Ti-6Al-4V is a common knifemaker alloy (Alpha-Beta alloy). Easy to color by, annodize by chemical electrolosis or by a propane torch even (heat).

Here is a reference for 6-4 titanium alloys http://www.espimetals.com/msds's/titanium64.pdf (Cut and paste the green into your browser, for some reason the ' is not recognized as being part of the url and is breaking the link). As it says here, do not use water to put out fires, this can and will happen when cutting. I am just beggining to experiment with titanium and already have seen a couple very small flare-ups, I keep my chips cleaned up very well from the bandsaw table (anyone notice the pictures of my shop, may see that I have 2 medium sized fire extinguishers on hand).

Didn't mean to make this a titanuim tutorial I hope it shows why titanium ($60.00 per LB) is really not a good blade material for every day use. I does make great backsprings, liners, and bolsters using the Ti-6Al-4V alloy.

I like D2 tool steel for a blade, more expensive than 440C. But it can be hardened to Rc60 using a regular temper and a cryo temper using dry ice (-112) or liduid nitrogen (-305) and not be brittle. It is a tool steel, just barely not enough chromium to make it qualify as stainless.

I also like an expensive steel from Crucible Particle but it is real pricey (powdered metallurgy technology). That would be CPM S30V http://www.crucibleservice.com/datash/d ... N=18478548

I also like the looks of M4 that they make as well as some of the Sandvick speacialty steels That D'Holder has been working with on a couple of Canal Street Cutlery knives.

Last but not least, I like 440C and some of it's variants (8A) and good old 1095 because I can buy that fairly cheaply.

It all depends on you standpoint, new to knife making, well I like 0-1, because you can heat treat more than once, scew it up and you can just redo it.

AFTER ALL THAT:

It all depends on your needs, I cannot pick just one, I can narrow it to 3 and that would be D2, CPM S30V, and 1095. There are far too many good steels to even narrow it to just 2 for me.

I find all the info you posted very interesting. Thanks a bunch. Metalurgy is a very complicated subject of which I know very little. I will say though, not long ago....at our local dump here in Garden Valley, Id., I picked up two sections of a sawmill blade. It was of the sort where the blade moves up and down....not a band saw nor a circular saw. It had carbide teeth brazed on it. It was slightly over 1/8" thick and about 7" wide. I completly wore out three sawzall blades cutting into three pieces (two cuts!). I sent the pieces to a friend of mine in California who's somewhat of a knife maker. He ended up with a very unique looking knife from it after first taking the temper out of it, then rehardening it and tempering it. It was extremely hard when he finished and "scary sharp". I sent along some beautiful Brazilian Tiger Wood for the scales....and he sent it to me so I could see his handiwork. I have no idea what kind of steel it was, but it "flaked" off somewhat when he quenched it after heating it for the hardening process. It actually added what I considered an attractive finish to the blade.

Dewman

That may be L6, another fine steel for knife makers. When I hear of saw blades, I think of L6. That is a fine steel for a knife.
Metallurgy is a very involved science of ferrous and non ferrous metals and the huge number of alloys.

When someone is learning about steels, I have found this page (borrowed from A. G. Russell's site) to be a good primer.....

http://www.agrussell.com/knife_informat ... index.html

Hukk has done a nice job explaining many points, and his experience is evident. I've found that sometimes it's helpful to see them compared to one another.

Charlie Davis, at ANZA knives, specializes in making blades from old files, saws, and trucksprings. Good working knives.

JMO.

Bill

Thanks Bill. Bill always has some great resorces to reference to. I have some old Nicholson files that are 1095. Some older auto spring steels are quite good, 5160, I think, newer autos may be different. 52100 (usually bearing races) is another good one. All are just excellent high carbon steels. Charlie Davis, at ANZA knives I hear is quite good I hear but I have not seen his work. I'm going to have to look him up to look at his knives.

I will anneal the files before I do any work with them. Heat them to non-magnetic, then quickly put them in a container full of vermiculite (from most any nursery) and let it slowly cool overnight. WEAR a respirator for this! (NOT A DUST MASK!) Some vermiculite has been found near asbestos deposits and there is some vermiculite on the market that is cotaminated with asbestos. I got this info from another site and regard it as being VERY important!

The point is that you must know what steel you are working with for a proper heat treatment and if you are ordering a knife to made. I believe most of the steels above can be made with a distinctive hamon line that comes from differentially quenching. Clay may also be used. I like a hamon, they are only available on some high carbon steels made by custom knifemakers. It can be done on Damascus (pattern weld) and is done by some, but in most cases I think it detracts from the pattern in the steel.
I took a picture off the internet that had an easy to see hamon, some are quite faint but enhance the blade anyway.

Learning about the steels a knifemaker uses will help you decide which maker to use for your perfect hunting knife. One that will last the rest of your life and can be handed down for generations.

Differential heat treating is when the blade has soaked in the kiln or furnace in a non-magnetic state (each metal has a different recipe or temperature and amount of soak time) and then taken out and usually oil quencehed on what will be the cutting edge (blade about 1/2 way in the oil) (water can be used for some metals). At the point where the steel is around 1/2 the soak temperature the entire blade is put into the quenchant. The result after tempering is that the spine of the blade is around 48-50 Rc and the cutting edge could be 58-60 Rc or whatever the knifemaker was shootng for determined by tempering temperature. This is how a knifemaker can pass one of his Journeyman Knifesmith (JS) tests. This is the test where they bend a blade to 90 degrees without having it break.

Well you can tell I had a Starbucks with 2 extra shots yesterday AND today, habit forming.

....what type of steel are files usually made of? This past winter, I threw a couple of old, worn out files into my wood burning stove in my shop and they stayed there all winter. When I cleaned the stove out this spring, I recovered them. They're now soft enough to be worked easily with another file or a bench grinder or belt sander. I've began to shape them, but the rehardening and tempering process is going to be a totally new experience for me that I'm kinda' looking forward to.....and will be my very first. I gave one of the blades a slight curve by putting it in the mitre gauge slot on my table saw and giving it a few whacks with a three pound hammer. Just enough to give it what I'd guess you'd call a semi-skinner shape. I always did love an adventure!


Dewman

Here are two of Charlie's pieces, one from a file, and one from a truck spring.

Hukk, here is a special page Charlie has up on the web...

http://www.msnusers.com/anzaknives/shoebox.msnw?Page=1

Here is his website...

http://www.anzaknives.com/

Thanks for sharing your experiences, and I hope dewman doesn't mind a small hijack...

Bill

dewman wrote:....what type of steel are files usually made of? This past winter, I threw a couple of old, worn out files into my wood burning stove in my shop and they stayed there all winter. When I cleaned the stove out this spring, I recovered them. They're now soft enough to be worked easily with another file or a bench grinder or belt sander. I've began to shape them, but the rehardening and tempering process is going to be a totally new experience for me that I'm kinda' looking forward to.....and will be my very first. I gave one of the blades a slight curve by putting it in the mitre gauge slot on my table saw and giving it a few whacks with a three pound hammer. Just enough to give it what I'd guess you'd call a semi-skinner shape. I always did love an adventure!


Dewman

Usually 1095, especially if they were Nicholson. If they were Chinese made, I wouldn't know what they were.
There are companies that do heat trearting, tempering and cryotempering for fairly decent prices. 1095 is a good steel to use an anti scaling compound available at Brownells as well as many others. Scale is tough on files, belts, you name it. As quenched, 1095 can be as high as 66 Rc, very brittle and tempering needs to be done to bring it down to 58 or 59 Rc. I think somewhere around 550 F will get 59 Rc, 600 would be about 58 Rc, but you need to get a recipe for that steel and use the correct temperatures and times. Some triple temper this steel and cryo temper before the last heat temper. Cryo will add .5 to 1 Rc and make the blade tougher. If that is the case, I would temper for 58 Rc. Good Luck!

0-1 is great to train on heat treating, if it gets screwed up you can redo it. You can't do that with 1095. With 1095, you'd probably have to anneal them and start over. 0-1, you can just redo the heat treat.

Old files have been used to make some really great knives.
That blade looks good. In the wood stove you actually annealed them. They heated up, and cooled slowly in wood ash, which is also used to anneal metal (cover heated steel into a container of wood ash). The slow cooling is the key and in a wood stove that retains heat, I imagine they cooled off right fine!

Thanks for the links Bill, I will certainly look at them. You made it easy for me.

....they were indeed Nicholson files. So, it's 1095 steel, eh?

Dewman

dewman wrote:....they were indeed Nicholson files. So, it's 1095 steel, eh?

Dewman

You bet and it's a steel that you will like because when it is properly heat treat and tempered, you can get it scary sharp and it will hold the edge very well. I like a cryo temper in the next to last heat temper (a heat temper should always be your last step). The liquid nitrogen cryo (-305 F) can raise the Rc by 1 point. Even dry ice can raise it .5 Rc at about 112 below. Both are supposed to make the blade tougher.
It is a high carbon steel, can develope a nice patina over the years and must be cared for like any carbon steel. It can and will rust if mistreated. But you will have one heck of a good blade. I have a few Nicholson files and they will be knives at some point in the future.

Hukk, I had no idea you knew so much about blades!! I hope that knife I sent you wasn't too boring

upnorth wrote:Hukk, I had no idea you knew so much about blades!! I hope that knife I sent you wasn't too boring

A free knife, are you kidding? It does give me ideas as this knife was designed for absolute efficiency. Nothing is wasted space, everything on it has a purpose. Even the metal inlay acts like a reinforcing for the lockbar. I find the blade interesting also, looks like a chisel grind on a folder, one side flat and the other flat ground, very efficient. I may try my hand at making one. It is a great knife for a newbie knifemaker to look at, as it is one that a newbie is likely to have more sucess with.

I did learn a lot about metallurgy working for Hewlett Packard and Agilent Technologies. A little about ferrous and a lot about non-ferrous metals.

Thanks for the Okapi knife, it has elements that are interesting and it MOST certainly gives me ideas on making folders. In that sense it was actually a perfect knife for me at this time.

Thanks once again and I hope to actually meet you next year instead of searching around. I left around 1:00 PM, I started to feel like a sardine.