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Information on old tool steel

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Hi everyone,
I have come across a few pieces of what I am told is a tool steel called 'Double Griffin'.
The stock I have is 20mm hex bar in 10 foot lengths.
I was working as a heat treater back in the nineties for eight years and I can remember seeing documentation on it
but never saw it come through the door. I am guessing it is either an O2, A2 or A6 grade but I am only guessing at this stage.
I was wondering whether any of the senior smiths may have heard of it. I believe it may have been made by either Comsteel in Australia or Eagle and Globe in the UK.
There is no reference on the internet that I can find, so if anyone has any information, I would appreciate it.
I will do some tests on it with heating and quenching in air and oil from around 900 celsius and see what hardness is achieved, but solid info would
be very handy.
Many thanks if you can help out.

Rob Kenning
Artist Blacksmiths Association South Australia.

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I've got some old Eagle and globe books at work with double Griffin in them, I'll look it up and post the results.
I seem to remember it was prized as a cold chisel material.


Thanks Phil.
I'd like to know forging temperature and heat treatment data so I can do
it some justice. By the way, the material is actually octagonal bar, so it was probably purchased with punches in mind.

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Yay, finally a reason for my collection of outdated tool steel guides!
Balfour's / Eagle & Globe.
Double Griffin- shock resisting steel. AS1239/ AISI spec: S100A.
C .35
Si .2
Mn .3
Cr 1.75
Ni 3.5
Forging range 850-1100 C
Annealing temp 750 C
approx. annealed hardness (Brinell) 220
hardening temp. 850-950 C
quenching medium: air-salt-oil
tempering temp. range: 0-550 C
working hardness, Rockwell 'C' 40-51
Applications: Ni-Cr shock-resisting steel. Punches, shear blades, chisels, snaps, wedges.

ps can i have some? ;)

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  • 2 years later...

Hi Rob


I remember my father [born 1920] trying to teach us as children about how to properly [and not properly]quench Double Griffin when used as a cold chisel. He'd heat up all of the DG chisel about 1 inch back from the cutting edge until it was all cherry red. He knew from practice exactly what colour it needed to be. He'd then quench it ever-so-briefly in oil to get the colours running towards the cutting edge, and they'd slowly 'run' just like the super-imposed time-line that you see during the finish of an Olympic swimming race. I always used to wonder where these colours came from but I now think it was perhaps in part from the oil acting somewhat like it does as a rainbow on water. I forget the sequence of colours as they 'ran' but I do remember the most crucial colour, which was 'a golden straw colour' [the pot[ential] of gold [cold?] at the end of the rainbow?], and just as this straw colour met the cutting edge was the time to quench the cold chisel out completely. He showed us how, if it was quenched too early, it'd be too brittle, and useless as a cold chisel, or too late, and it'd be too soft. Too prove all of this to us kids, as there's nothing better than the old adage of "seeing is believing", he'd place the cutting edge of the cold chisel on the top of some very old and well-used railway line and then lay into the chisel carving pieces out of the railway line. As you may know, railway line, having manganese in it, is designed to work-harden with the rolling stock's wheels giving it a good gradual pounding over the years and the day's heat. I have seen a few large shearing sheds having roof trusses made completely from old railway line and anyone with any sense should never dare to enter such places simply because old [used] railway line can snap like honeycomb at any moment, seemingly of its own accord, or just in a cold [chisel] snap. :^)


If you wish to get hold of some good old Double Griffin I suggest you speak with some elderly railway fettlers who worked on the "permanent way". Some of their old chisels and tool steel may have, and just on the spur[line] of the mom_ent'erprising, decided to take an early retirement and accompanied their users home in their lunch boxes. As a kid I used to watch these fellows at work with their large 6-inch-wide Double Griffin cold chisels being held in tongs and then belted with big sledgehammers. They were forever having to take pieces out of the line as it stretched in the hot weather and use by traffic. They'd mark the rail all round as best they could before snapping it with a special bending tool if it hadn't already snapped by itself. Sometimes they'd even let you take home a short piece that you could carry to use an an anvil.

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You're welcome Thomas. It looks like not too many posts find their way onto here. Another way of making a good cheap cold chisel is to grind the tip off of an el cheapo cold chisel and then weld a thin bead of Stellite on in its place and then grind it to a chisel point. Stellite is good for lathe cutting tools and keeps its edge even when very hot.

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This is turning into a GREAT thread! thank you for starting it Rob and thank you Mr. Peruser for the descriptions. Now all I need is some Double Griffin so I can give it a try. I do sooooo love a good cold chisel.


Please continue, I'm SURE working DG isn't the only thing you were shown as a kid. <wink>


Frosty The Lucky.

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