How to get the most out of salvaged and recycled steels

Keith_H said:
For the record, My favourite part of files are the teeth :D
Click to expand...

LOL

From a bladesmithing standpoint, my least favorite part is the teeth,... Unless, I want the look of the teeth and the texture of the file to show in the finished blade…. In that case, nothing but a file will do.

From the standpoint of the file as a cutting tool in and of itself,... I love the teeth! :)
 
I've had good luck making knives out of mid 60's to late 80's GM leafsprings. And even the coil springs too. Bringing it to a bright red (in full sun) to forge to shape and normalize 3x after, then quenching in ATF tempering to 400F 2x for 2 hours, seems to make a great blade that really takes a lickin with out too much edge damage. But I cant hardly get it to forge weld for nuthin! Also had good luck forging hawks and hopefully soon a hammer or 2 out Dodge Cummins deisel steering linkages which I believe is 4140. maybe someone else can chime in on definants


Jason
 
If I were to make the more modern style knives and hawks I would maybe use new steel,but I don't. Most of you know I mainly make axes and tomahawks. The customers that I have will most of the time request salvaged steel. Just so they can say "Man this use to be a so and so. Can you believe it". I occasionally make a knife just to get out of a funk I'm in at the time. I do sometimes use new steel. My main supply is salvage (plow parts,steering linkages,farrier rasps,leaf and coil spring,axle and ballpeen hammers). The ball peen hammers I do buy new by the case,but it would be considered recycled because it is reforged. The reason I use so much recycled is because it just cheaper and easier to find than larger sizes of new steel. On my pipe hawks do use a lot of new steel.There again I will forge weld in a piece is recycled steel for the cutting each. It is really nice when your done to be able to see the teeth of the old rasp showing. I heat treat all my hawks and axes for use. I quench in ATF and Temper with a torch. All without any compliants. If you have ever been to a camp you would see they do get abused.
I am not going to dispute that new steel is not better. I am just saying for the style of what I do. The salvage steel is better. Or least my customers do.
Just my ramblings and 2 cents worth.
 
Tai,This looks like it can be the start of a really good and informative thread....

I would like to see all the guys that say they like to use scrap post up some recipies for the begginer smith..Say how they test and heat treat a certain item,like a saw blade or file or what ever they like to use...
Here is my basic starting reciepe for a unknown steel (posted in the other thread once already,but felt this was a good place to say it again)


Lets start out with,do you know if it is a stainless steel or carbon,Stainless will barely pull a magnet...If the magnet does not stick to it then you have rel stainless and it wont work for a knife only a guard,yes stainless will stain if it is around rusty steel and you wont know it isnt the rusty steel unless you check...If the magnet barely pulls to it you will have a series of stainless and unless you have a way of getting it analized I would use it for guards...Now on to the next step if it isnt stainless.

Have you tried a simple quick oil quench after heating to non magnetic,then doing a bend test in the vice,if so did it break or bend?

Ok It broke,now your on your way to making a knife that will cut....First lets do about 3 normalizing heats on this piece of steel then one more heat and put it in your vermiculite or closed gas forge(with the forge full hot and gas and air off)and closed door.Let the steel cool till it is completely at room temp or 24 hours later....

Now forge the blade to your desired shape...lets normalize the bar 3 more times and let cool to room temp to relive any stress caused by forging....

take the blade to the grinder and shape it then do about half your grind on the blade and polish out to about 400 grit...

now back to the forge and normalize 3 more times ..while you are doing this heat your quench oil to around 120 deg. (or heat a 1/2 inch rod of mild steel to a quenching heat and put it in tour quench tank,of a gallon or a little less) now after the third normalizing heat is cooled down bring the blade up to non magnetic and quench...check the edge with a new file,it slid across the edge ,great, now put it in the oven at 350 for 2 hours,if the edge is to hard for the file to just grab in bump the temp up to 400 and try it again,if this is still not soft enough bump it up again at 25 degree intervals untill you get the edge were you want it....now go finish the knife and do some cutting see if it works good or great or doesnt hold a edge ....Now find some known steel and try it and compare the 2 and see if you want to keep using found mystery steel or known...Good luck in your project and if you hve anymore questions just holler and I will see if I can help out any more...

Bruce

On a side not...I am just thinking that since you have a way to forge and grind then you probably have some old motor oil around to quench in or at least a jug of olive oil,and a water bucket...This is the problem with found steel,you dont know what to quench in and unless you have plenty of steel to do some testing on your better off to use that piece of steel for a guard or buttcap.....we can only guess at the steel ourselves and give ou ideas to try but all the experimenting has to be done on your end as we cannot do it for youand we cannot guarantee that it will work at all....If you want known results for your knife then use known steel to get them..Now if your curious-want to play-or experiment- have fun and heart ach-or just dont have anything else for steel,go for it,but we cannot give you a exact recipe for it and sorry to say but you will have to be the scientist,or send the piece of steel out to have it analized....
 
I started forging with leaf springs from a 1962 Ford Galaxie, treated it as if it were 5160 and it worked fine.

This week I acquired 75 lbs of known 5160 and forged a couple of blades with it this weekend; I treated it exactly like I did the springs and it responded exactly the same.

After forging and the blade is straight and looks pretty much like you want, I do some rough grinding, straighten up all the edges, get the majority of forging marks out then normalize 3 times; I like to remove the scale between every heat cycle because if a scale bubble occurs, it could insulate and cause a cold spot.

After the final normalize I quench. I've been doing 2-3 quenching, just because I read that edge holding ability of triple quenched blades is significantly better. I have not verified this for myself and there are many that will argue that there is no benefit. One day I will make a couple of identical blades and test the difference in single or triple quenched blades.

After quenching it's time to temper. I like to temper at least twice, once in the oven at 325 - 350 F (gives an actual 365 - 410 measured on the blade with a IR thermometer) and once with a torch for a differential temper on the spine, taking the spine to a nice deep purple for impact resistance. I have a dish of water or a wet cloth near just in case the edge starts to get too hot I can cool it. I'm going to shoot for no higher than 360 actual in the oven and light straw on my next blades and see how they do.
 
Wellllll. I don't generally go for a really unknown steel. That hasn't been really heavily addressed- You may not know exactly what steel soemthing IS, but you can generally tell what gteneral chracteristics the steel will probably have if it's used for a given PURPOSE. Of course, anything made in China this doesn't apply to. I'm not being prejudiced against the chinese products, this is experience talking.

At the least, the steels I recycle are known to be used for a given type of task- such as hay rake, plowing discs, springs, bandsaw blades, HC rebar (spark test, quench test. Spark test, quench test.)

Having access to the forum, the internet, and a lot of blacksmiths, I can often spend several fun hours figuring out the most common steels for a given era and proveneance (example, not all Deere harrow discs are the same. the good ones are good, the crap ones are EXACTLY as useless as trying to forge down a modern chinese lawnmower blade.)

Saw blades, as I've mentioned before, I pretty much uniformly treat as 15N20 if I don't know any better- it's a fairly simple steel to HT right and won't really screw up a 10xx steel anyhow. If I KNOW it's a different type of steel, or suspect it from testing after a HT, I change things up. There's not a whole lot of variation out there- UHB-15 (15n20 minus the nickel), M2, I imagine I'll find some 8670m saw blades some day. The majority of the recycled bandsaw steel i've used SAYS what it is anyhow. (and what it says is that it's UHB-15N20 or UHB-15) - I will note that some of the thinner stock variants have major grain issues and sometimes don't anneal very well. The .060 UHB-15 is HARDER to make a stock removal knife out of than anything else I've worked with.

I have been practicing and using for production the interrupted quenching technique Kevin described to me, works great for the lower 10xx (I can't say about 1095) and 15N20.

I treat coil springs as 1075ish. I've worked with a couple pieces of leaf spring assumed to be 5160 and they worked out into good knives, but the leaf springs are a bit too variable for my taste to actually go BUY at a junkyard, and anyhow, I have 100 odd pounds of new 5160 and about as much 1084 now, so what's the point?

For heat treating most of what I work in, and most recycled unknowns that respond to a "bit above magnetic, hold for 5-10 minutes, quench in canola or safflower" pattern, I temper once for 1 hour, vinegar soak, temper 2x more for 1 hour, and THEN do my differential with the edge in water. Today I read about deker's experience going to blue 3 times and I might just see if the differential done multiple times does anything for me.

Tempering temperature? depends on what the blade is doing. I'll accept a bit softer for a heavy chopper in convex than i will a bird and trout in scandi grind.
 
koyote said:
I temper once for 1 hour, vinegar soak, temper 2x more for 1 hour, and THEN do my differential with the edge in water. Today I read about deker's experience going to blue 3 times and I might just see if the differential done multiple times does anything for me.
Click to expand...

Diffential tempering was described to me the same... with edge in shallow water, three times, very soft and small flame to heat as slowly as possible. Spring temper is a temperature, yes, but it takes a time to actually get it, was the explanation I got.

Mike
 
Last edited:
Mike Krall said:
Diffential tempering was described to me the same... three times, very soft and small flame to heat as slowly as possible. Spring temper is a temperature, yes, but it takes a time to actually get it, was the explanation I got.

Mike
Click to expand...

I use a soft and small flame, and it takes a fair amount of time to do it, so maybe I'm just reaching a high enough temperature for long enough. This could be one of those cases as with the triple quenching- not REALLY needed, or more like oven tempering, where a single long soak sometimes will do what 3 shorter soaks will do.

I'm definitely gonna see.

Of course, then there's (cue evil music and big fat reverb) ZONE tempering.
 
Guys I got some crazy hamon recently out of forged W1 with a $3.00 tube of ZAP furnace caulk I picked up @ Lowes. After I put it on, I brought it to critical and quenched in brine.
I will edit this post later to post a pic of it.

Jason
 
Off the top of my head, I believe "manganese steel" is also non magnetic at room temperature, but is non stainless. It is hard and tough. but I don't think it has enough carbon for a good blade steel.

When ever you can, I think you are best off salvaging "known" steel, in the form of marked "drops" etc... Check with steel suppliers, spring shops, saw shops etc...

Next to that do like Koyote and salvage tools or parts that have been known to make good knives in the past and run a few tests on them.

If you have a truly unknown piece of steel, try to get at least a general idea of what it is and how to heat treat it before you try making a blade from it. This will involve some testing as Bruce suggested.

The first thing I do is hardness test the piece with a file to see what state it's in. If it is already in a hard state, then it is a good indication that it may be suitable for a knife blade. Also, check it for obvious fractures and flaws.

Here's a thread on hardness testing with files:
http://www.bladeforums.com/forums/showthread.php?t=609040&highlight=File+Test

Next try spark comparison testing. You will need some samples of known steel to compare sparks with, so start saving some now.
http://en.wikipedia.org/wiki/Spark_testing_metals
http://www.capeforge.com/Spark testing.html
http://www.alexdenouden.nl/04/midden.htm

With quench/hardness testing it is important to first determine what the quenching medium is, air, oil, or water, which should also give you some clues into the chemistry and heat treating temperatures, soak times etc...

A hot torque or "twist test" can help you determine the level of hot malleability and "quality" (or purity) of the steel. Do the twist test from a forging heat on a square section about 1/2 to 3/4 wide and about one inch long. Count the number of rotations you can make before it starts to shear and also look to see if the high spots or corners are smooth or rough.
 
Yes Tai you are correct,Manganese is non magnetic and will rust and look just like a piece of cast iron,so I would hope someone wanting to make that first knife would at least know that a piece of cast iron wont work anyway.Most Manganese I have run across at the yard has come from RXR equipment.Big pieces may work for a anvil but not a blade.We have to be very careful and not get any in our cast iron as it get a whole load rejected for just 1 piece found in the load...

I agree that it is better to find something that you know what the piece is,but I have gotten pieces of steel from a machine shop that was rusty and the guy from the shop says that itis a piece that they used to have hardened but forgets what it was,so it is at the beggining of not knowing tou will have to start.

What I was hoping was that some of the guys would put up their receipes for say a file or plow disk and that way we could get different receipes and different known pieces to start from so the begginer could just look here and say I have that piece and wow a receipe to start at..

Hope that makes sense.

Bruce
 
An important thing to consider with all this is that we need to look for steels that are “suitable“, which may vary depending on our concept, type of blade we are making, shop set up (equipment), skill and experience levels etc., and whether or not we plan to forge or use stock reduction. However, there are some types that we can weed out from the get go, (with the exceptions of possible special applications), stainless steels (with the exception of high carbon stainless for stock reduction), low carbon steels, cast iron, and wrought iron. For sure we can weed out galvanized steels.

Just for starters:

Galvanized steels can be recognized by the bright rough or crystalline silvery looking metallic coating.

Stainless steels, as has been mentioned, are sometimes non-magnetic or barely magnetic, have a smooth bright silvery look. High carbon stainless steels are air hardening.

Low carbon steels are soft and won’t harden significantly.

Cast iron often has evidence of a sand mold on the surface, is brittle, melts at a low temperature, the fractured surface looks dark grey and has a course grain structure. Cast iron is not hot workable.

Wrought iron is soft, won’t harden significantly, and has a bright fibrous look on the fractured surface. Etching will also show a fibrous structure.

Of the steels that may be suitable, we should be able to at least narrow them down with some simple testing into several basic categories based on their chemistries.... #1. Medium or high carbon, #2. Quenching medium, air, oil or water (shallow or deep hardening,... simple or alloy). #3. Stainless or non-stainless. Once we know the general type of steel, then we can look at the manufacturer specs for other steels in that category and start to narrow things down. For example, "high carbon non-stainless shallow hardening".

Simple deduction... Mystery steel detectives! :)
 
Last edited:
I agree Tai..

On that galvanized note,if the bar is a little tusty and yur not sure if it is galvanived dont use it! if you do by chance put it in the forge and t starts smoking andflaming,shut down and get out till the smoke has cleared out,zinc fumes can make you sick and definately will poison you,I was told years ago that drinking some milk will neutralie the poison but it still isnt good for the lungs....

Lets see,Plainer blades was one I used to hear allot about trying,anybody try these..

Bruce
 
What would you guys be hunting for in S. Louisiana? There's commercial fishing and seafood processing, oilfield construction, exploration, production, refining, sugar cane & other ag, lumber in the central and northern parts of the state, shipping with the Intracoastal and the Mississippi, etc.
 
Springs are everywhere. Most will most will make a serviceable knife. Just need to do the testing. My first knives were planer blades and I think they are D2. I tried to anneal with no success and then we wont even talk about drilling. Not all planer knives are D-2 though some are 1095. I would love to find a pile of the 1095. Though I normally use known materials I do like to make some unusual pieces out of found materials. I am working on getting an analysis done on a few do give me a heads up on HT. Even knowing the composition of the material does not guarantee the HT process. It may need to be adjusted a little to get the best performance for the given use.
 
I havent tried the planer blades myself...I was lucky to start with old antique lumber mill circular saw bladesthat were between 2 and 4 foot across,You know the kind without the carbide teeth,that had to b hand filed to sharpen.I always thought they were L6 and heat treated them as such,they made excelent hunting knives...

Years ago we couldget scrap from the Nicholsen plant in Alabama and they sid the scrap files were 1095 at tht time,so I liked using them and heat treated as such,if yu get a off brand file you may just be getting a case harened piece of steel and it isnt anygood for a knife...

Bruce
 
You must log in or register to reply here.
Back
Top