Good Morning all.
 
I was luckly enough to have a person with the metal zip gun scann some steel for me. These are old 28" buzz saw blades. The samples are from the hub not the teeth.

I can tell you for a fact that when I have hardened either of them they snap like glass. The  first blade did not like a water quench anyone ever worked with steel like these?

By the way I do plan on getting known steel for anything that matters but I think these will be great fun to work.
 

First Blade
LA-1215 2.8
Iron/CS 3.2
Fe 98.23
Mn .614
Cr .366

 

Second blade

LA-1215 2.9
Invar-36 3.2
Ni 1.08
Fe 92.46
Mn .521
Cr .309

I know a wee bit about blade steels but nothing at all about a metal zip gun. Blade steels must have sufficient carbon, your testing may tell you that they at least contain enough to harden.

Notable absent in the above data is the carbon content, I also wonder about you saying that the sampling was from the hub not the teeth. If that means that the teeth are different I wonder if they are add on teeth. I have used saw mill blade that have had the teeth ground into the outer edge of the whole. They worked wonderful..The steel used was made to hold and edge throughout a word day on the mill and then be resharpened and relused. Add on teeth are hard and have different properties. I worry about the rest of the blade being selected for its ability to stay in shape and provide a base for the teeth and not for edge holding ability.

Most of wot I took the time to type is based on conjecture as you did not really provide a lot of info.

From what the hand held metal analyzers (guns) for portable metal analysis (I like calling them zap guns lol) said it looks like the carbon comes from the steels they were alloyed with LA-1215 and Invar-36. The 1215 has .9% Carbon but the Invar 36 not so much, only about .2% carbon. Thing is these guns have a margin for error so this is a more of an estimate.

The first blade has replaceable teeth and is about 3/16" thick. The second blade has the teeth cut in to the saw and was about 1/8" thick.

On both I have tried and they passed the back yard carbon test. I bet they will pattern weld nice with some 1095 and make some neat patterns.

the second one with the nickel should give a bright layer, the first one maybe not so much contrast to simple steels. 0.9 carbon is fine,   the 0.2 is for color only

The one that may only be .2% is still REALLY HARD for what ever reason. I do not plan on that being more than for letter openers and camp knives.

It's all the chrome and manganese making it hard, the low carbon helps keep it from work hardening and maintains it's flexibility. Big circle saw blades have to have some flex or they just don't work right.

 

Now if you were talking about a good old fashioned misery whip you'd have some really good knife stock in hand. In the 1045-1050 range typically.

 

Frosty The Lucky.

Frosty
I do have one but that is a modified small two man that I (6'8" and lots of mass) can use to a point by my self. I have some rotary drum blades that I got for next to nothing from Tractor supply that are in the 1045 range.


And I used one of the 2 man saws every day for 6 months in the mornings while I was in high school. Still remember the sound.

 

Frosty,

 

Looking at this steel and that it does break like glass when hardened and bend when annealed does it stand to reason that this would be good steel for thicker blade knives or hawks? Should I harden some strips and then heat treat at 350, 400 and 450 to see what they do?

Or do you think I should only use it with high carbon 10XX in a pattern weld?

 I have a bowie that I cut from the second blade and did stock removal to shape. I have not heat treated it at all just what was left from that saw blades HT and what the cutting process did. I put an edge on it and chopped a pine 2x2 in half with no harm to the blade.

 

Remember, you need to multiply .9% by the alloy number (2.9%).  This is a very tiny amount of carbon.  This steel will not harden as you hope.

 

I have tried spark testing several large saw blades with integral (not replaceable teeth).  They have tested as high carbon.  Here, the spark test is an excellent sanity check.  From the observation that the steels did harden, I would expect the carbon to be on the order of .7%.  Spark testing in this range is accurate to .1%.  Way better than the gun.  Where's ciladog when you need him.

Well I think it is time to make some film and let the IFI folks get a look at it.

I have some known 5160 and some suspected 1045 for control samples.

 

Thanks for the info.