Dick Hanscom provided this update on his coin striking experiments:
I did another experiment with the drop hammer, pushing it down the runners. Almost got a full strike. I need to make arrangements to really throw it down. I am sure that will do the trick. Sledge hammer did even better, but I wimped out and didn't hit it as hard as I could have for fear of missing!
I played with the new screw press. It punches out blanks (so far up to 32mm, 2.4mm thick for my trial strikes with the drop hammer) and will strike a 14mm token. I'll progress up to see how large it will go with one twirl of the swing arm (I am sure there is a technical name).
Jim Duncan writes:
I'm a collector, not an engineer, but I once watched a man using a drop hammer. Every time, just before he dropped the hammer, he painted the top of the upper die with something. I asked what it was, and the answer was "kerosene". He reckoned he got an extra bit of 'push' as the kerosene exploded under the impact. I can't answer for the efficacy of it, just that he did do it, and reckoned it worked.
Dick Hanscom adds:
Kerosene....hmmmm.... I think my wife thinks I am enough of a danger to myself without adding an explosive. May have to try it.
Dick Johnson writes:
I am waiting for Dick Hanscom to get so frustrated with his home minting kit that he is going to throw something against the wall.
Dick, take your die to a professional private mint and have them strike it for you. They will know what to do and have the proper equipment to do it.
I just hope you haven't received your mail order home heart surgery kit yet.
Now how much fun would THAT be? Dick's been working on a revised edition of his book on his coining experiences. Thanks to The E-Sylum, Dick's been in touch with Eric Holcomb.
Eric Holcomb writes:
I've already been in communication with Dick, and we've worked out a simpler version of the calculation for his book that uses English units from the outset.
This is actually a very interesting and complex problem. As it turns out, Dick has some good hydraulic press data that show why it's difficult to get a good single strike for a coin or token of this size (1 oz. gold), due to work hardening of the metal. As I pointed out, that's what the U.S. Mint discovered in 1907 for the high-relief double eagles. Would a “hot strike” be more successful? – that would be interesting to know.
To read the earlier E-Sylum article, see:
MORE ON COIN STRIKING PRESSURE CALCULATIONS
Wayne Homren, Editor
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