Inexpensive/easily found tool steel.

Here's an example of 1045 heat treated to the maximum and tempered just enough so it doesn't break like glass. ... Kinda... One of the pieces did chip as you can see.

I just made these about an hour ago and would estimate their hardness at RC 56-58 which is about as hard as 1045 can go. These pieces are too small to test with a Rockwell impactor or Leeb tester. I know they're hard because not much happens to them when you drag a file over them. They were turned about 1.5 thou oversize, heat treated then, used emery cloth wrapped around small pieces of metal flatstock to "grind" the surface to final dimensions. These pieces are for an experimental side-project of mine and are very tight tolerance.


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This one didn't survive the heat treating and it cracked/chipped. -Happens when I don't pay attention.
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The point is, you can do a lot of fine work on small pieces like this, using common metals like 1045 and/or 4140. Tool steel has specific applications and I believe there are 4 basic types -and each has a specific purpose (hot working, cold working, impact resistance, temperature resistance). Then, there are super-alloys which have combined features of the 4 basic types.... You just don't need all that for home hobby work.

Ray
 
Can you get enough material for a 1-2-3 block from an earlier cast iron V-8 Cylinder Head? Shouldn't be too expensive.
 
If you have the means to provide enought heat long enough (forge or foundry furnace) you could just use mild steel and surface harden it. Machine it to near finished state, put it in a vessel with some carburizing compound (charcoaled leather works) and heat for a while. The Clickspring guy did it to make some files on a recent YouTube video, I thought his method was something I might try. You should be able to use aquarium charcoal if you have some Cherry Red to mix with it. Then you can grind to final size. As stated above, 1-2-3 blocks are pretty cheap, but 2-4-6 blocks are not so this might be a cheap way to make some of those, as well.
 
When I took machine tool in vo tech, we surface hardened parallels made out of cold roll, we took charcoal briquettes, crushed them to a powder, if memory serves me correct the powdered charcoal was put in a metal box and lid put in heat treat oven for about an hour with parallels “soaking” absorbing carbon on the surface then quenched. That would harden them up a bit to where a file would skate across them.
 
I made 1-2-3 blocks back when I was an apprentice back in the '60s, out of 0-1 leftovers from a die job, I heat treated them in the shop's Johnson furnace packed in peach pit charcoal to avoid decarburization, and tempered them in a molten nitrate salt bath (50/50 mixture of sodium nitrate and potassium nitrate), which will stay liquid down to a bit over 300 deg. F. (and also is used for nitrate bluing) I then ground them to size, or a bit over, and reground them to nominal size many years later when I had my own surface grinder. Junk steel is cheap, but tool steel is fine grained and with proper heat treatment is dimensionally stable over time, this may not be true with junk steel. I have two other sets of blocks, imports, but the ones that I made myself are "special" to me. I also made two sets of parallels back then too, these drilled for lightness, as are the 1-2-3 blocks.
 
A good source of chunks is buying SOLID 123 blocks. Shars has like 5sets for 30 bucks if I remember correctly. Large chunks are harder to come buy as scrap. Unless you find a honey hole machine shop and get the drops.
 
Cadillac said:
A good source of chunks is buying SOLID 123 blocks. Shars has like 5sets for 30 bucks if I remember correctly. Large chunks are harder to come buy as scrap. Unless you find a honey hole machine shop and get the drops.
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Likely they would be hardened and require annealing before they could be machined, not real convenient.
 
What kind of steel are the bars from a weight set? I see them at yard sales and on Craigslist/FB marketplace for cheap/free.
 
Mark Fogleman said:
What kind of steel are the bars from a weight set? I see them at yard sales and on Craigslist/FB marketplace for cheap/free.
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They are often nearly impossible to machine because of hard spots from being chilled in the mold, and also sometimes have voids in them. They are made as weights, not machining metal. Sometimes they cut great, sometimes not at all. Same with bed frames. Sometimes the tooling burned up and broken messing around with that stuff can cost more than good and known metal would have cost.
 
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