Plow knife

Rey

Well-Known Member
I have some plows I picked up at a salvage yard. This are the V shaped plows and would like to know how to heat treat @ temper after I shape them into knives. Would it be the same as using farrier files and leaf springs as to heat to non-magnetic, quench in mineral oil, clean the black stuff off from it and put in oven for 1.5-2 hrs. to temper twice if need to, formula needed? Rey in Texas
 
There is a reason that mystery metal is called mystery metal. You are just going to have to experiment to find out how to heat treat them.

From what I remember they are most likely be made of a simple steel so I don't think a long soak at temperature will be needed to prior to hardening. Normalization is pretty much normalization. I would start tempering at 400° and see test the blade, even to destruction, to see how that works and adjust accordingly.

Doug
 
plow steel ( old stuff ) is generally made from 1055 a lot of good blades have been made with it . I f you go to rail yard maintenance ask them for some rail straps or crossovers ,, They are made from 1095 a known. 1055 will make a decent sword and will take a good hamon
because its pretty low on Manganese ..... I would not go over 350 -375 on temper. I like to experiment . Or try some bush hog blades
which usually 5160 H which means it is guaranteed to reach a certain hardness. Contrary to most beliefs 5160 will take a hamon .
It responds well to a torch and edge quench...... Bubba
 
If it is something more one the order of 1060 then you might want to keep a brine quench in the back of your mind if you are having problems getting a good edge on it. I would try something like peanut oil or one of the commercial fast quench oils first but if that won't give you a good edge you just might have to grit your teeth and cross your fingers and go to water or brine.

My person guess would have been something more on the order of 1080 for maximum hardness from carbon content and there is more than one grade of plow steel.

Doug
 
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The old plow steel was almost always 1050 or less .
the newer stuff is usually something better . I just bought some high grade plow steel that is 1095 . A brine quench is always good , I use that on W-2 it makes the Hamon nice and whitish color . the ways to make your steel perform better are endless ....... Bubba-san
 
It still boils down to how old is old and who made the plow knives. Nothing to do one way or the other but give it a try and see how it comes out and adjust from there if necessary. Mystery metal is mystery metal.

Doug
 
Doug is so right about mystery steel, but it can be fun to play with. Non-magnetic is not enough. Take it up about another 50F. Quench in fast oil. If that doesn't harden it redo it with a brine or water quench.

If it actually does harden, try tempering at about 325 to take the stress of and then increase if necessary to prevent chipping.

I get the impression you have a supply of these. Keep notes to remind you what worked - and just as importantly, what didn't work and how it failed.
 
I can see how being salvaged or recycled could make a difference in the application of metallurgy, approach to heat treating and/or methodology etc.,… but am a bit confused on how whether it’s for himself or someone else could, objectively.?.

For something like this, for starters,… maybe try 1500 for just a few minutes, quench in a fast oil and temper at 400 for an hour once, (on a wedged shaped sample piece similar to the cross section of a knife) and see what it does. If you don’t like it and it doesn’t respond well, either try tweaking your temps., and times a little,… or find another piece of steel that likes it like that... :)
 
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I can see how being salvaged or recycled could make a difference in the application of metallurgy, approach to heat treating and/or methodology etc.,… but am a bit confused on how whether it’s for himself or someone else could, objectively.?.

Relax, all I did was ask the question, I made no statements at all about any differences, metallurgically or otherwise. Your assumptions reveal a defensiveness that confuses me as well, well not really. Not that I owe you any explanation, but the fact is that I am currently working on my lecture on cost strategies in knifemaking for Ashokan and part of it includes steel source choices for the hobbyist and professional, it was simple curiosity for my demographics. Thus all I had was the question.
 
I had a very interesting time very early on in my knifemaking. I was using steels ranging from very old large chainsaw bar, to some 1" round sections that had areas of splines left even though they'd been cut into 8" or so sections with a chop saw. I assumed those were axles. Plus some spring looking things that might have been ends of forklift forks. All these steels passed the spark test and made fine knives after I experimented with the heat treatment some. I couldn't tell you right now if they were better, or worse, than the Admiral sourced 1095 I use a lot. They were "good enough".

I was beating the rounds and larger spring sections into flatter billets and cutting a preform at the tip for the larger bowies. I learned a lot and I suppose that's what mattered.

I also sold every one of those early knives and it was a very awkward statement to have to tell the buyer, sometimes over eBay or a forum or the phone "Well, it's some pretty much junk I ended up with." "It's a chunk of chainsaw bar." "It might possibly be an axle." Some of the buyers liked that I'd made a hair-shaving sharp and durable knife out of the stuff, but a lot of the others were confused, and my explanations of "Hey, it's got enough carbon to harden, I had it Rockwell tested and it's a heck of a lot better than your Buck knife." oftentimes were misunderstood. Some of the clients were suspicious of my abilities when I outright told them "Well, I used a real trial and error method to figure out to get these done 'cus I have no idea of the actual makeup of the steel - but believe me, it's a good knife."

It wasn't a good thing for my professionalism and as soon as I could I grabbed some 1095 from Admiral and off I went. I feel much more confident in being able to tell the customer "It's a batch of 1095 I bought from a supplier in Illinois in March last year." End of story. They know 100% what they're getting and I have some AISI standards to start with for the heat treatment.
 
The “market” is big enough for all kinds. I think it’s true that some collector/users actually prefer recycled steels, for whatever reasons. However, I don’t think it means they are superior from a purely metallurgical or objective standpoint.

Using recycled/salvaged steels means taking the science into your own hands, as has been suggested. For some, and/or in some cases, that approach maybe superior to trusting someone else.

Either way though,… just because you can, doesn’t necessarily mean you should.
 
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hi,
i made a comment on a similar post that working with "unknown steel" might be a good hobby project, it doesn't make sense if you are trying to sell knives. to spend the time to shape, bevel, and finish, then find that your plow steel is not a medium/hi carbon steel but a low carbon high alloy blend like HY80 that is never going to harden. just my toosense.
scott
 
Scott, the idea is to deduce what the steel is and/or is capable of closely enough, before trying to make a knife out of it. It's really not as hard as it sounds. However, it does take some testing and experimentation up front. You have to use some "reverse scientific method". In that way, you can take most of the mystery out of it and with a bit more effort, nail it. But first,... you have to know what it is you are looking for. It's important to weed out the ones that aren't, first.

Whether you should or not, is up to the individual and is more subjective than objective.

Since the end use of a tool dictates the heat treating,... then in reverse, if the tool performs up to standards then we can safely assume that the steel and heat treating must have been at least adequate.

In the final analysis, the name of the steel is not as important as it's actual working properties.

The use of recycled steels in knife making has been around a long time and I doubt it’s going to go away any time soon. So, rather than debate whether anyone should or shouldn’t use it, it seems more productive to try and help those who choose to use it, get the most out of it.

The O.P. asked for a formula or starting point, and some were given. I’m really just trying to clarify the methodology of it, which can be interesting, scientific and educational.
 
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To add a few personal thoughts and observations: learning to use recycled steels, using home made tools and such, is primarily more recreational/educational than professional in my opinion. When we started the original Neo-Tribal Metalsmiths group (which was known for using recycled materials homemade tools and such) here in Tucson,… it was just for fun, and was. Most of us had conventional shops and equipment as well, but we wanted to explore a different methodology and approach to metalsmithing/bladesmithing. At that time no one really expected or wanted it to become a commercial venture, especially me. However, as time went by, we learned new things and gained experience at it. A few of us got pretty good at it and discovered and/or helped create a market and demand for that type of work. I’m still not sure if making that shift was good or bad, but that was the reality of it. It was at that point that all the trouble really began,... power plays, politics, counter reactionism and conceptually irrelevant criticisms etc. We enjoyed it, but moving into commercialism took a lot of the fun out of it. It changed it, like anything else. However, it was never something I expected to do exclusively/indefinitely and also made other types of knives as I still do. At this point in time, I don’t think the “Neo-Tribal” label really fits my work as well as it once did. It’s been close to 20 years since then and my work has gone through numerous changes, but the knowledge and the experience I gained through "The Great Neo-Tribal Experiment“, will always remain a part of my work and still applies to almost every aspect of it,… whether the steel is store bought or salvaged/recycled.
 
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No more "mystery" steel thanks to technology....Kinda takes the fun out of it....

http://www.ebay.com/itm/Thermo-Scie...ay-Fluorescence-Analyzer-w-Case-/231037322227

Not all the mystery, those guns typically can’t read carbon content. I have had to tell more than a couple of sources that they didn’t have the steel they thought they did when they went to one of these for identifying scrap. To be portable and only $16K the gun only reads a band in the heavy metals spectrum, so often people will get a Cr, Mn, or V reading that “looks like” the steel they are wishing for but the rest doesn’t line up.

And there is where human error comes in. I have had people tell me that they know what their steel is because one of these yard sorting guns said it was 1095, 5160 etc… The gun doesn’t go “zap” and then says “O-1” or “L6”, all it does is read elements present, in the end the person running the gun makes the extrapolation and guess as to what is, and may even program the gun to give that answer but it is still human error. It would also be awful tough to tell any of the 10XX if it doesn’t read carbon. There is an awful lot of misconceptions floating around our business about spectrometers and what they do.

Now of you want to really nail it, for more like $50,000, you can get a bench top laboratory spectrometer that will read the wider spectrum, but it will also run you around $5,000 a year just to keep it calibrating and running. Don’t ask me how I know all this:2:
 
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