Steel type for Machinist Gage Blocks

[Latticino]

A friend and I are working on forging some Viking style forging hammers using a wrought iron "core" with forge welded faces for both the large face and cross peen.  I have an old, rusty  1 1/2" x 1/2" x 18" gage block that I plan to sacrifice to use for face material.  I hot cut a section off last night and quenched it in water at a dull orange heat and it hardened up wonderfully, but if anyone has any idea what the typical steel type is for these I'd appreciate more accurate information so I can address proper heat treatment.

Thanks

[Anachronist58]

http://www.google.com/url?q=http://www.nist.gov/calibrations/upload/mono180.pdf&sa=U&ved=0ahUKEwieh-nR_KzNAhVMOFIKHd9SB6sQFggSMAM&sig2=1-BLu0JewkbfVvC2lGacoA&usg=AFQjCNGaSPtIg8eihcynUqRxbH0JLlogTA

Section 3.1 page 12 calls out 52100 as a prolific composition, but there are many variations. If a brand and serial number are still.visible, the exact composition may then be sourced, possibly.

Chromium is touted quite often as an ingredient.

Published 1991

Robert Taylor

[Latticino]

Thanks for the feedback.  The stock did seem to be quite tough, so I wouldn't be surprised at all if it was 52100.  I think one side had a serial number on it, but I may have torched that when I hot cut it...  Seems to work pretty similarly to the tank turret ball bearing I tried hand forging a while back (2.5" diameter bearing, extremely difficult to hand forge).  Will probably make excellent hammer faces though.

[BIGGUNDOCTOR]

I wouldn't think it would be good for a hammer face as it may be prone to chipping. Something more like 4xxx series would be more impact resistant. At one time that would have been a VERY expensive gage block, or was it just a parallel? 

[Latticino]

It might have just been a parallel, I'm not a machinist.  I have no idea what it cost, it was just rusting away in a bucket down in my father's basement.  He probably got it at a garage sale somewhere.

I plan on tempering it down after the quench using my rudimentary heat treat oven.  Found out the other day that it can get up to 1600 deg. F with little trouble, so should be able to use it to both anneal the hammer head before any grinding and eventually temper it there.  If I can temper it down to 58 HRC (per ASTM tempering twice at around 450 deg. F) I would figure it to be OK, but I'm not sure.  I've only made hammers out of solid 4140 and wrought with 1075 faces in the past.  I've read that 52100 makes good tough knives, if heat treated properly, so wasn't initially worried about it being brittle.  What do you think?

Thanks all for the information.  As usual, members on this site are very helpful

[BIGGUNDOCTOR]

If it was a parallel, I doubt it is 52100. All it would need would be a dusting on a surface grinder to be be usable again.

Before I went any further I would take a sample, and heat treat it like you would the hammer. Then cover it with a heavy cloth, and wail on it with a hammer. The cloth will help deflect any fragments that may come off of it.

 

[Latticino]

I did try a hardening test on the material, but you are correct I probably should have checked into tempering it as well.  Jumped the gun, but ran out of time before getting to use a coal forge with my smithing group (my forced air natural gas forge struggles just a bit getting up to the high forge welding heat that is recommended for wrought).

Well, I don't know what kind of steel it is, but I struggled quite a bit today with forge welding it onto the wrought iron body.  Did pretty well with the first face, but when I got to the cross peen I ran into some trouble.  As far as I know from my limited experience with wrought, I needed to heat the wrought up to high yellow heat, at least, to weld. Unfortunately the face material (possibly 52100) would crumble when I hit it at that elevated temperature.  Clearly whatever it is I used has a rather short working range, though it does forge pretty well (but slowly) at orange temperatures.  It was fine when I could heat the wrought from below first, but once I had a face on that side I had trouble.

Right now it appears to be bonded pretty well, though I do have a few cracks in the cross peen face I'll need to attempt to weld back together as I finalize the form.  Still, if it is 52100 I certainly would recommend using a different tool steel for hammer faces.  My buddy was working in tandem with me, also making a hammer, and had much better luck with 5160 and 1084.  The previous wrought Iron/hard face hammer I forged had 1075 faces, and I'll probably stick with one of these easier tool steels in the future.  Just got lazy and used what I had in the thickness I wanted to work with.  Valuable lesson there: 15 minutes of upsetting and resizing the 1084 I had on hand would have saved me a lot of grief.  I have lots more respect for those who can work with the more exotic tool steels after this.