How to get the most out of salvaged and recycled steels

Steve,

I think you are right. I was finding steel that was supposedly known but had been laying in the back of warehouses for a long time. I quickly got into having the steel tested.

The reason I couldn't just go with the "supposedly" and work though the steel to a high level of function is due mostly to my nature... I've got "needs to know".

I really do think there are a lot of folks who are very happy working on and discovering how to deal with an unknown steel, though. It's a really neat idea in a lot of ways.

Mike
 
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I think the whole purpose of this thread is to demonstrate ways to determine the type of steel a mystery steel is. Not just the carbon content. I think a lot could be learned here. The road to #2 "Maker has put in the time to know or determine optimum heat treat for a given steel." would be shorter if run thru some of the tests in this thread. If I came across a quantity of possible quality steel I would get it analyzed, but, I believe that there is a method by which one could successfully narrow the steel type down so that one could have a excellent start point to begin HT experiments and work your way to a quality treatment. There is no reason one could not become very good at this. It is not the simple way and would take some work and knowledge. Hardly a newbie task. If I was going to go into found steel knife making one of the first things I think I would collect is a bunch of well marked pieces of known steel for comparison purposes. I imagine that in the past that even many foundries analyzed their product in such a manner. Plus I am sure the HT of known tool steels was arrived at with some testing. Learning about a steel and its properties and how to HT it is interesting no mater if I pick up the spec sheet or learn it the "hard way". Either way it becomes a known material. I like it.
 
JasonSCarter said:
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
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Just wondering what kind of brine solution your using? I don't realy have much luck with w1 and keeping an edge, it gets hard but seems to wear quickly.
 
Steve Hayden said:
Actually the best way to determine chemistry is to send a piece out for mass spec.

I have nothing against recycling steel given one or both of two conditions:
1. Steel type is known,
2. Maker has put in the time to know or determine optimum heat treat for a given steel.

Just knowing you have a high Carbon steel will not help if you try to get the most out of 1095 with slow oil, or if you try to maximise the heat treatment of an alloy with V or W that needs a soak by just heating to non-magnetic and quenching.

If you do these things you may get a knife that works OK, but maybe you will never know what the steel is really capable of doing.
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If you think you might have something like 1095, you can always water quench a sample, leave it dead hard and keep it for comparison hardness testing as a reference.

If it’s a high carbon deep hardening alloy you will be looking at longer soak times, higher temps etc, with an air or oil quench, in which case for sampling or hardness testing purposes, you would be better off over shooting than under shooting.
 
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For the newbies,... I think you are best off sticking with a couple items like files and leaf springs, until you get some experience and confidence with them, then move on.
 
do all of the common steels we use become non magnetic at the same temp ,or is there enough of a difference to use this as another test.
 
just trying to throw some ideas out there.if you had a range of tests surely you could have a bit of a flow chart type thing going on...
 
caseynz said:
do all of the common steels we use become non magnetic at the same temp ,or is there enough of a difference to use this as another test.
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The steels below the eutectoid point of 0.84% C (approx.) become non-magnetic at the same temperature. The steels above eutectoid differ.

All reach fully austnitized at different temperatures, dependent on carbon amount (primarily) and alloy type and amount.

Mike
 
I am doing a bit of an experiment myself. I have sent a piece of a sawmill bandsaw blade off to have analyzed. I have another piece from right beside that piece that I am going to have shot with a PMI gun. These work by a small radioactive source and use a type of Xray to tell most of the alloys in a sample. Their biggest fault for knife steel ID is they do not ID the carbon content. But, in an application like a saw blade there are a limited number of steels used. If one knows the Cr, NI, Mo etc. One should be able to match it to one of the steels used a for an application. Like a big spring set. If the PMI says the chrome is around 1% and the Mn is also around 1% I would know it is in the parameters for 5160 and have a very good stat point for my HT. I am interested to see how close the PMI gun does in comparison the a true analyzor. Most scrap yards have a PMI gun aa do many metal shops. I see them as a fast, easy way to get close on many of the alloy components.
 
If I was going to go into found steel knife making one of the first things I think I would collect is a bunch of well marked pieces of known steel for comparison purposes.
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Great point! I think that's an important key to the whole thing,... "comparison"!

I usually use what ever is laying around the shop but,.... I think putting together a couple good kits with lots a samples for comparison spark testing and hardness testing with a file would be most helpful... samples of different "known" steels, and of known alloys with different known numerical Rockwell hardness values, for comparison.

I wish I had been more diligent and aware of that, from the very beginning...
 
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Mike Krall said:
The steels below the eutectoid point of 0.84% C (approx.) become non-magnetic at the same temperature. The steels above eutectoid differ.

All reach fully austnitized at different temperatures, dependent on carbon amount (primarily) and alloy type and amount.

Mike
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I've got to correct myself on this. Should be steels below about 0.55% carbon turn non-magnetic at the same temp... not steels below eutectoid point of 0.84% carbon. Non-magnetic temp. then follows AC1 temp. for the carbon/alloy amounts to eutectoid point.

Yeah, I know, more than you wanted to know and not the way you want to deal with it anyhow...

Mike
 
Question: Does steel temperature affect the spark test? For example I have two pieces of antique steel: one wagon seat spring from an old Springfield wagon, and an old Amish buggy leaf spring. When I tested the wagon seat spring I got some complex sparks, but when it was heated I really got complex sparks.
 
I just got a email back from the tech dept at nicholson file ..... and he said to heat treat it with best results as W1 steel..

so save up the nicholsons and give it a go !


Greg;):thumbup:
 
Greg Obach said:
I just got a email back from the tech dept at nicholson file ..... and he said to heat treat it with best results as W1 steel..

so save up the nicholsons and give it a go !


Greg;):thumbup:
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I have a boat load of old worn out ones. They all spark test to real close to the same amount of carbon,... on the high end.
 
The things I worry about with files in general are stress risers and micro fractures due to the teeth... and being left in a more or less dead hard state,... although I've never had one snap on me...

I wonder what they quench them in?

The carbon content does seem much more constant and consistent than some of the new bought W1.
 
I have just been told I can have the leaf springs from a '53 Chevy truck (leaf on both front and back, no coils). I haven't seen the springs yet to see it there is any marking and a quick search on the net has not come up with any information about the composition of the springs. Does any one have any suggestions on how I might find out the make of these springs? I figured if anything they would make good hawks or hatchets.

Thanks,

Mark
 
another test is heat it and bash it.some steels are real hot hard and others just flow nicely.
 
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