Guillotine style coin press

[UncleBenBen]

Hello all you great folks of GRF.

I wanted to share something we came across over the weekend at a Renaissance festival. I think many of our resident fabricators and builders may get a kick out of it.

I know the idea of turning our recovered metals into coins and stamped bars gets kicked around from time to time, and I really like the thought of it. This guy had quite an interesting way of doing it!



He was actually stamping pendants, but it's the same idea. He had what were essentially pre-made coin blanks of copper and Sterling with hoops already attached to hang the pendants.

I don't know if you can see it in the photo but the blank is sitting between the bottom and top die in the open 'mouth' part at the base. The bottom die sits in its hole, the top slides down the top hole and rests on the blank, and the part that is struck by the falling 'hammer' slides in the hole to rest on the top die.

Once the hammer was cranked to the top he centers the blank between the dies, pulls a brass pin from the swivel on the hammer and BAM! One strike was all it took, and got some pretty impressive detail.

A few more pics...



I wish would have asked what the brass bar in the welded on cup was for.





I'd love to build something like this one day. The dies would be pricey, but I'd like to have some with Au or Ag with atomic number and all like they appear on the periodic table. I don't know the back sides. Maybe just "Fine Gold" and room to hand stamp the true weight and/or purity.

I hope y'all get as big a kick out of this as I did!

Ben

 

[FrugalRefiner]

I like it! I don't suppose you got any pictures of the finished coins/pendants did you?

I like the Ye Old WD-40 in the first picture. Truly renaissance period. :lol:

Dave

 

[Refining Rick]

HA! I spotted the Vans foot bindings. I used to love going to those things. Middle ages and Civil War reenacting. Talk about authenticity differences. Ren fairs, so wrong, but great imaginary fun.
I have a few of the silver coins they stamped with these things at the SCA wars. Pretty nice with good detail. But alas, that was long before I got into reclaiming.
I did not see a "stop" to keep the hammer from bouncing and double striking. Maybe the rope does that too?

 

[UncleBenBen]

I like it! I don't suppose you got any pictures of the finished coins/pendants did you?

I like the Ye Old WD-40 in the first picture. Truly renaissance period. :lol:

Dave

We bought one so I could watch his rig work. I'll get it from the wife when we get home and post a picture. Did you see Ye Old rubber chicken on the table also!?! The guy was quite a character, he had actually done a bit of silver refining recently.

I did not see a "stop" to keep the hammer from bouncing and double striking. Maybe the rope does that too?

I wondered about that also. The rope stayed up at the pulley when he pulled the pin to release the hammer. Maybe there was something in the posts the hammer slide in, or that is what the brass had to do with somehow.

I wish I would have found him first instead of as we were leaving. I probably would have paid more attention since I hadn't put my beer goggles on yet!

 

[Justincase]

I did not see a "stop" to keep the hammer from bouncing and double striking. Maybe the rope does that too?

I think the brass cylinder off center look like a sprung buffer stop.
It would allow high energy impact's to penetrate for a strike but stop low power bounces from making a second impression.

 

[Refining Rick]

AH. Yes, I see. That looks to be the case. Maybe there is like a valve spring type thing under the brass? Anyhoo, pretty cool. Now I'm dreaming of making something similar just to stamp gold buttons.

 

[UncleBenBen]

I think the brass cylinder off center look like a sprung buffer stop.
It would allow high energy impact's to penetrate for a strike but stop low power bounces from making a second impression.

I was looking at the pictures in my phone again as they are a bit more clear(a very small bit!) and I think you may be right. Even though it looks like the brass bar is too low for the hammer to hit, I think it may just be the angles making it appear that way. On the bottom of the hammer I can just make out what looks like light brass colored marks off center that line up with the brass bar.

It looks like four marks that would match up with the four positions that the base could be placed when setting up the rig.

Edit to add..
I chatted with the guy about refining a bit and told him to check out the forum. Maybe he will stop in and let us know!

 

[4metals]

Any idea what kind of force the thing generates?

 

[Barren Realms 007]

I'm also wondering if the wooden boxes to the right are all of the dies he has had made.

 

[UncleBenBen]

Any idea what kind of force the thing generates?

I couldn't begin to quote you any numbers, but it hit hard enough to shake the ground. I thought I had been hearing blasting on a newer nearby highway. I'll tell you he was a big ole boy and still looked like he was struggling to crank the hammer up the pulley.

The pendant might say more about the force, as it did this to a copper blank in one hit...





I think it looked better before the chemical aging treatment, but that's what the wife wanted.

 

[UncleBenBen]

I'm also wondering if the wooden boxes to the right are all of the dies he has had made.

Those are indeed his dies. Although he didnt make them.

I had pulled my little gold button out of the folded paper towel in my wallet and let him look at it and had just mentioned maybe trying to stamp it when I heard his wife say the dies cost about $200 each. I promptly put the button back in my pocket!

I could just see the dies hitting together because the gold was too soft, shattering, and me having to hand over my gold in payment!

 

[Barren Realms 007]

I'm also wondering if the wooden boxes to the right are all of the dies he has had made.

Those are indeed his dies. Although he didnt make them.

I had pulled my little gold button out of the folded paper towel in my wallet and let him look at it and had just mentioned maybe trying to stamp it when I heard his wife say the dies cost about $200 each. I promptly put the button back in my pocket!

I could just see the dies hitting together because the gold was too soft, shattering, and me having to hand over my gold in payment!

ROFL

 

[Topher_osAUrus]

Couldn't the force be "ballparked"

With the ye-ol wd40 and ye-ol monster-mead he has in the background, one may be able to "guesstimate" the side of the cylinder. And, if it is made of iron, the density could be calculated. Freefall speed is given, due to gravity.

So, could we not just use net Force=Mass x Acceleration

Mass we can just guess (for simplicity sake) say the cylinder is 50cm tall, and 25 cm wide which would give around 24,543 cm3
take that by the density of iron (around) 8.0g/cm3
gives about 196 kilo's
say it freefalls about 1 meter (again, just a guess)
gravity accelerates at 9.8 m/s/s

*math*

I could only remember this bit of it, I know there are alot of other things that get taken into account for the sum of force, like stopping force, which could not be more than 1mm or 2, I would assume, otherwise the coinage would be obliterated into nothingness.

I'm no "math scientist" and I haven't taken physical science in 15 years, so I am a little fuzzy on the precise formula's and what not, but, I think it could be a *ROUGH* estimate of force that is achieved by the "known" variables.


I was planning on going along and figuring the rest, but had to go pick up my kiddo's from my mother's house, and now I don't have the time. -my estimation is probably way off anyways.
Maybe Ben could give us some closer dimentions?
-topher

 

[g_axelsson]

The problem is that the force is depending on the material that sits below the lower die. How fast is the deceleration?

Easiest way would be to measure how far the top die is pressed down when it is hit by the weight until it bounces. That number also includes how far the wooden blocks below compresses. From that you could calculate the force needed for constant deceleration. Multiply with a factor 1.4 to get a top force estimate.

Compare it to a crash bag, longer time and distance means less force compared to hitting the steering wheel with your head, same initial speed but spread over time makes a big difference.

Or you could so some googling and find out which force is needed to mint a copper coin of comparable size. The flow of the metal looks good so the forces is probably in the same range.

Göran

 

[UncleBenBen]

Topher, I'll grab a tape measure and try some guessing if you want to do the math. It would just be guesses though. The way he had it roped off, I never got closer than about 10 feet to it.

I was thinking more about the way the hammer hit. It was like dropping a big ball of wet clay. It dropped and it stayed dropped. I was expecting it to bounce halfway back up the slides, but it didn't bounce at all.

That makes me wonder if it might have a bunch of lead shot in it that would give the same effect as a 'dead blow' mallet. If it did it wouldn't matter much if I guessed the dimensions of the steel spot on, the actual weight could be anywhere.

I think Göran's right, Google may give a better answer than I can!

 

[Refining Rick]

http://quicksilvermint.com/

 

[g_axelsson]

http://quicksilvermint.com/

The mint is operated using controlled amounts of accelerated gravity by raising a 150 lb. hammer to a height of 9 feet. The coins set between the two dies are struck with an incredible 40 tons of force!

That was easy! :mrgreen:

... but I'm not sure about the "accelerated gravity", last time I checked the gravity is by all practical means constant all over the world. :lol:

Göran

 

[Topher_osAUrus]

http://quicksilvermint.com/

The mint is operated using controlled amounts of accelerated gravity by raising a 150 lb. hammer to a height of 9 feet. The coins set between the two dies are struck with an incredible 40 tons of force!

That was easy! :mrgreen:

... but I'm not sure about the "accelerated gravity", last time I checked the gravity is by all practical means constant all over the world. :lol:

Göran

Maybe there is a rift between parallel universes, causes spatial distortions in certain "soft spots"... Or maybe ive been binge watching too much fringe lately :mrgreen:

 

[Justincase]

http://quicksilvermint.com/

The mint is operated using controlled amounts of accelerated gravity by raising a 150 lb. hammer to a height of 9 feet. The coins set between the two dies are struck with an incredible 40 tons of force!

That was easy! :mrgreen:

... but I'm not sure about the "accelerated gravity", last time I checked the gravity is by all practical means constant all over the world. :lol:

Göran

Maybe there is a rift between parallel universes, causes spatial distortions in certain "soft spots"... Or maybe ive been binge watching too much fringe lately :mrgreen:

I understand that to a practical working understanding the slight variation experienced on earth are almost undetectable. but Gravity is not a constant in the sense that it is the same every where only that is exit's where ever there is mass, it's attributable force is dependent on the mass of the body.
The acceleration of gravity(as it was called in early papers) can be defined by measuring the change of velocity related to change of time for a free falling object:


g = dv / dt (2)

where

dv = change in velocity (m/s, ft/s)


dt = change in time (s)


A dropped object accelerates to a speed of 9.81 m/s (32.174 ft/s) in one - 1 - second.
•heavy and light bodies near the earth falls to the earth with the same acceleration but you would have to alter the value of "g" for other planetary body's.
It would be interesting to observe the difference in acceleration you can find when the moon is excreting a counter force such as when it is high tide locally, if only mass was not a factor in the relevant effect as well. I doubt you could find a test subject as large as an ocean. the amount of influence on a smaller test sample would be correspondently hard to detect.
Yet again the Maestro incorporates a principle in his invention that officially was not observed by anyone for several century's .

 

[Topher_osAUrus]

Yea, gravity is not constant everywhere...if it were, I think the universe would have seen the *big crunch* long ago.

In the show "Fringe"-(great, GREAT show by JJ Abrams)
Their world, overlaps a world from a parallel universe, in the same plane of space/time. Where they do not encounter one another until Walter opens a portal to go to the other side and rescue his-"Walternate"'s dying son.
In the show they go over a lot of "science fiction" things that are based upon science and technology that is *very* much close to a reality, if not already a reality.

One episode, a irate man lost his child due to a form of DNA mutation, where the child had no bones, and was lost at 3rd trimester. The man then used the chemical weapon (which he was working on previously, which lead him to his mutation-passed on to his offspring).

It just made me think of HF acid.

The blue mist was loaded into a childs pullstring toy, when the bossman pulled the string, a big cloud of mist came and moments later, his body lay on the ground, in nothing but a pile of everything but the bones.

It is an excellent show, very well thought through, and one of the few shows I actually watch.

Nerdy as it may sound/seem, both of my boys are named from JJ Abrams shows
Desmond- from Lost (as he is the one who gives up his life, to save the world-and he can see the future, and more)
Hendrix- from Fringe (a combo of Walters grandfathers name, a man who devoted his life to science and the pursuit of knowledge; and Peter's kids names....and a little bit from Jimi Hendrix, as me and my wife love music)

Long rant...again...
and way off from a coin press.. but EVERYONE should know these shows! they are great.

-me