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#1 horgad

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Posted 06 September 2007 - 12:39 PM

I am interested in coining using copper, silver, gold, and maybe some other "soft" metals and I am having trouble figuring out how big of press is required to get good results. From what I can tell most modern coining is being done with at least 50 tons of pressure and lots of it is being done with 200 tons of pressure or more, but if you look at some old coin presses they were hand cranked. So the question is do I really need a 50+ ton motorized press or can I get away with a hand cranked press operating at a much lower pressures?

Oh and I guess that I really need a screw press and not a fly press, but I hope this post is ok here. From what I read the screw presses get you more pressure, but don't have as big of range of motion. Is that correct?

Be nice to the noob [Peace}

#2 PTsideshow

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Posted 06 September 2007 - 01:02 PM

To start with [Beer][Peace}[Peace}[Beer] now thats over with we will jump on ya with both feet and then some[hysterical]. Depending on the type of impression you what to leave. Most gold and collectors coins are double struck to make a crisp clean bright impression. On both sides, you are aware that the higher the pressure of the die stamping the harder the dies need to be. And the longer the die run the harder the dies with in reason.
You didn't say if you want an imprint design or a raised design. And if you have any idea on how the dies are created for coinage. They start out with a original about 12"dia and it is reduced twice some times more till it cuts the finished sized medallion. The edges of the blanks are rolled with the lines or imprints before the two faces are struck.
I have seen a guy at the North American Model Engines Show use a 12 ton bottle jack and making collector copper medallions for the kids.
He was doing only one side.
If you are only doing a limited number of strikes you could get a way with a small air/hydraulic jack and a H frame.
Jewelers used the fly presses for blanking medals and charms copper and annealed silver/gold. The copper or other base metal were then plated. The fly press was a faster way than a screw press for limited number runs of things.
Others can address the fine points of the fly press. As I have only limited exposure along time ago in a galaxy far away. Making tool crib tags by the hundreds[hysterical].
hope this will give you some help if not try another question[rockon]
[Laugh]
glen

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#3 horgad

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Posted 06 September 2007 - 01:33 PM

Thanks for the reply.

Well I am thinking more along the lines of selling these items for their metal value and less as collectables. As such, I have no problem with a one sided design nor do the designs have to be elaborate. If needed, I can even live with just lettering and no design if it means that I don't have to start out with a mondo press.

As far as imprint vs. raised, same thing if imprint takes a smaller press, than that is big plus for going in that direction at least to start.

What I don't want to do is buy a press and then find out I need a bigger one , but at the same time space and money are an issue so I can't just go for a monster press the first time around.

As for the die, I have no means to make one myself and will be using some type of custom die place such as this one:

http://www.osborneco.../customdies.htm

By the way, if anybody want to talk about or recommend custom die makers, I am all ears.

As for the bottle jack, the thought crossed my mind as I was looking at automotive related presses that were make using a bottle jack. Maybe I just need to go out in the garage and start experimenting and just what damage I can do with a jacks to various metals. Or maybe I can find a place that will let me experiment with the fly/screw presses before buying one.

#4 Alexander Metal

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Posted 06 September 2007 - 01:42 PM

Oh and I guess that I really need a screw press and not a fly press, but I hope this post is ok here. From what I read the screw presses get you more pressure, but don't have as big of range of motion. Is that correct?

Be nice to the noob [Peace}


According to John Crouchet's flypress video, screw press is just the American term for a flypress. Only blacksmiths and Englishmen call them flypresses. Don't know if that helps you at all.

#5 PTsideshow

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Posted 06 September 2007 - 01:57 PM

The screw jack you have read about is a motorized press operated screw the following book will answer the questions you have from a two part hammered die set up to other related questions that will come up.
oppi cover.jpg
You might what to check out your local library as the current cost is around $120.00 US. It is worth three times that amount in the knowledge it contains. But I got lucky and got it at garage sale.
The ISBN 0-385-04185-3 Double day is the publisher.
the following site is a forum about jewelry stamping and forming. There is a book out on using a bottle jacks in a press frame for blanking and stamping jewelry parts. It isn't a real active site but there are a number of experts on it.
Hydraulic die forming forum
Since you have contacted a die company you might what to ask them their recommendations as to the equipment to make their dies preform.
Since you seem to be leaning in the area of the noble metals. The pressures you will need will be less then stamping out a nickel or some other alloy other than say sterling silver.
Hydraulic Die Forming For Jewelers & Metalsmiths By Susan Kinglseyhere is the book
Hydraulic Die Forming for Jewelers. By Susan Kingsley. "One of the best new books on jewelry making techniques" says Jo Reveka, in a book review published by the Lapidary Journal. This long awaited book by noted artist and metalsmith Susan Kingsley is the how to do it textbook on hydraulic die forming, the technique that employs a heavy duty hydraulic press to shape metal. Clear, step-by-step instructions on everything from equipment, non conforming dies, conforming dies, blanking dies, and design inspiration. Find out how to make your Jewelry by blanking and forming with the assistance of a hydraulic press. 95 Pages, softbound.
[Peace}
glen

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#6 PTsideshow

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Posted 06 September 2007 - 02:34 PM



Oh and I guess that I really need a screw press and not a fly press, but I hope this post is ok here. From what I read the screw presses get you more pressure, but don't have as big of range of motion. Is that correct?

Be nice to the noob [Peace}


According to John Crouchet's flypress video, screw press is just the American term for a flypress. Only blacksmiths and Englishmen call them flypresses. Don't know if that helps you at all.


A number of trades that require a constant pressure to achieve results use terms to describe equipment that gets thrown about willy nilly.
Bookbinding, leather work food/juice making and art print making Use a type of screw press of a yoke style.
The screw press of jewelry, medallion and coinage making since the steam age generally refers to a motorized press that operates a screw shaft drive to punch or stamp dies.
The fly press that metal smiths use, be them jewelry,gold, silver,black or white smiths. Are hand operated for control and finesse. that can be as somebody posted the picture awhile back of a 50 tonner desk top to large. These have been called screw presses, they were also called blanking presses, medal presses ect.
in the ornament trades.
And it is true about American's,Englishman ect nomenclature for some items. Sort of like the same church different pew.
the fly press comes in two main styles the H frame and a C frame or goose neck type.
Then we can get into the hammers which also can be used to stamp or impress coinage.
No that i have made you a hopeless confused mass on the floor in a semi fetal position [Laugh]
I will let you ponder the question that comes to mind? Why me![Beer]
[Beer]
glen

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Cicero

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All the usual and standard disclaimers apply. Do not try this at home, use only as directed, No warranties express or implied, for the intended use or suggested uses, Wear safety glasses, closed course, professionals only

#7 horgad

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Posted 07 September 2007 - 06:02 AM

Excellent information. I went ahead and put a hold on Jewelry Concepts and Technology at my library and will work my way through the others if I can find them.

After doing some further research, I think that I will hold off on coining for now and the higher pressures that it implies. Instead I will start with stamping which should be good enough to start with.

Now I just need to decide on which press or power hammer to get which is as you said a bit overwhelming. But at least with stamping I have less worries about wasting money on something that will be underpowered for the job.

Anybody got a favorite plave for custom steel stamps such as these:

http://www.steel-stamps.com/Stamps.htm ?

Thanks

#8 PTsideshow

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Posted 07 September 2007 - 07:39 AM

If you are talking about shapes or linear forms, repeatedly stamped into silver, copper or gold. you don't need any kind of power hammer other than an Armstrong powered hammer and home/studio/shop made tool steel stamps.
This is if what you want to do is along the lines of the southwest Indian style belts and bracelets with the stamped pictograf's on the various elements.
All of the stamps,punches other than the hallmark stamps I have used I have made. the sterling, carat gold stamps are purchased for my local supply house.
Using Silver,Copper and or alloys of gold when annealed for the noble metals they are soft enough that you can wack the stamp with a good hammer and get a nice Itaglio imprint, or depending on the stamp a cameo type raised surface.
Tool steel from the local industrial supplier oil hardening O1 type or water hardening W1 Preference for either one generally by use or instructor.
Again I will say you will find the answers you seek in Oppi's Tome.
wholesale tool
McMasters-Carr
J&L industrial
And I believe that Production Tool & Supply has a location in your area any of the above carries the tool steel for punches, of course you can use punches,chisels and hardened cement nails that you retemper after marking the stamps
[Worthy]
glen

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All the usual and standard disclaimers apply. Do not try this at home, use only as directed, No warranties express or implied, for the intended use or suggested uses, Wear safety glasses, closed course, professionals only

#9 erikgem

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Posted 07 September 2007 - 10:41 AM

[quote=horgad]
Thanks for the reply.


What I don't want to do is buy a press and then find out I need a bigger one , but at the same time space and money are an issue so I can't just go for a monster press the first time around.

As for the die, I have no means to make one myself and will be using some type of custom die place such as this one:

http://www.osborneco.../customdies.htm


I have done considerable coining using my Z&H 50 ton screw press similar to the grey one in this link. http://www.shirepost.com/ShopTour.html It will strike coins up to about 50 cent size depending on the metal.. Coining takes a lot of pressure. I once struck up a solid 10K gold medal 3 3/4" in diameter. I had to find a plastics mold company that had a 700 ton hydraulic press. After several anneals we finally got it struck. Before I got my screw press, I used a 50 ton hand operated hydraulic arbor press. It works, but you get very tired after pumping it up 100 times. I have also struck up small items with a hand operated screw press.
As for the dies. You can buy equipment to make them for less than having the dies made. A Gorton 3U pantograph can now be bought on Ebay for 200 to 400 dollars. You can hand make a template fron cellulose acetate and cut it into O1 steel. I will give further instructions if you want.
If you get to Buffalo,NY you are welcome to look at my equipment.
Dave Anderson

#10 Whitehair

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Posted 09 September 2007 - 06:30 PM

horgad,

I"m in central Illinois and have 4 flypresses. You are welcome to drive over and get some experience on them. Email me, if you are interested.

Whitehair

Oh and I guess that I really need a screw press and not a fly press, but I hope this post is ok here. From what I read the screw presses get you more pressure, but don't have as big of range of motion. Is that correct?

Be nice to the noob [hysterical]



#11 horgad

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Posted 12 September 2007 - 07:38 AM

"A Gorton 3U pantograph can now be bought on Ebay for 200 to 400 dollars. You can hand make a template fron cellulose acetate and cut it into O1 steel. "

I never thought die making equipment would be that cheap, but then again I never heard the word pantograph until just now. [hysterical]

This board has been a great source of information and has helped me fill in some blanks in my knowledge. Currently, I have a ways to go before I get to the point of stamping and coining, but I bet that I will be back here with more questions. And I will definitely be taking people up on their generous offers of field trips especially if they are near Indianapolis.

Stage 0: Learning and Cost Estimation (I am here!)
Stage 1: Refining metal
Stage 2: Casting blanks
Stage 3: Finishing blanks
Stage 4: Stamping or coining

#12 hanscom

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Posted 21 December 2007 - 09:15 PM

I would also like to know how many tons would be needed to strike tokens. I currently make silver tokens up to 1 inch in diameter and gold at 14mm and 19mm with a 3# hammer. I want to do gold up to 25mm and 30mm. The strike on the 1 inch silver is not really good, but I basically am a coward and don't really want to increase my striking pressure for fear of hitting my hand! I have to believe that I am not generating anything near 2000# pressure on the 1 inch blank.

I would prefer a screw press to hydraullic because it is closer in technology to a hammer. I hate admit it but I am thinking of trying to build my own drop hammer.

As for the dies, they ain't pretty, but they are sufficient for my purposes, and I engraved them with a dremel tool in cold rolled steel.

The 19mm, 5DWT gold token can be seen at http://www.mosquiton.../AKGold5DWT.jpg

Dick Hanscom
Fairbanks, AK

#13 PTsideshow

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Posted 22 December 2007 - 03:51 AM

[Beer][Welcome]Since you found this thread won't go over the stuff posted before. Other than to say check out Oppi's book if the library has a copy. You also could try using the die or dies in the jaws of a large vise. Since you are going towards the hand forged look. A vise is just a small sides ways screw press.

As stated before the alloy of the metal, size, annealed well, and clarity of the impression and if it is impressed into or on top of the blank.Would determine the size of the press needed.

Modern Marvels has had two real good programs on minting coins and Also How's it made has down a segment or two. Check out the web sites for the info.

You could always try wacking with the hammer and the die/dies when they blank is hot, but not close to the point of change of state.

The other thing with a large press or drop hammer you have to consider is the foundation to isolate the vibration from the ground around the hammer or press. Others on this site are better to address that part of if.

Have you tried putting a handle rod in to the side edge of the die block or make a set of top and bottom dies blocks like a tong to keep the hands away. And hold the blank in place.

You could always try casting the metal into ingot molds made to the size and shape you want. This would still give a rustic look to the item, But be easier to accomplish with out a press.

Again :)[Peace}
:)
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#14 hanscom

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Posted 22 December 2007 - 12:49 PM

Thanks very much for your comments. I am not going for the rustic look. However, that is all I am capable of artisticly, and I want to do all myself.

I have a guide block for the top die, but my hand is still too close. I missed the other day, the hammer slipped off the die, and I broke one of the guide blocks.

The idea of a handle coming off the guide block is a good one, one that I have thought of but not acted on.

My main material is native gold (unrefined, melted gold dust). This tends to be fairly soft, but not as soft as pure gold.

I am not looking for an exact number. Just a general one. Considering that I am not going for a high quality artistic product with perfect surfaces, etc., is 2 tons enough? Or 6, or 10.

Thanks again.
Dick

#15 PTsideshow

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Posted 22 December 2007 - 01:54 PM

well its not such an exact science using unknown assay of metal, the trace metals in the gold dust could raise the hardness. Are you melting the dust in to slugs or blanks then you might consider pouring them into ingot slugs. I really don't know how the hammers are classified and since there are a number of different types drop, trip ect. each with their own pluses and draw backs. I do know that they are using 10, and 20 ton jacks in H frames for jewelry work and blanking dies, along with urethane rubber, and Masonite for copper, silver and gold sheet. I'm not passing on the question, But can't be more specific that what already has been posted in the first 12 or so thread responses.
You can check this site out and the question section as they have people doing all kinds of pressing. They may take a day or two to answer.
answers to all your pressing questions
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All the usual and standard disclaimers apply. Do not try this at home, use only as directed, No warranties express or implied, for the intended use or suggested uses, Wear safety glasses, closed course, professionals only

#16 Alexander Metal

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Posted 24 December 2007 - 12:57 PM

A number of trades that require a constant pressure to achieve results use terms to describe equipment that gets thrown about willy nilly.
Bookbinding, leather work food/juice making and art print making Use a type of screw press of a yoke style.
The screw press of jewelry, medallion and coinage making since the steam age generally refers to a motorized press that operates a screw shaft drive to punch or stamp dies.
The fly press that metal smiths use, be them jewelry,gold, silver,black or white smiths. Are hand operated for control and finesse. that can be as somebody posted the picture awhile back of a 50 tonner desk top to large. These have been called screw presses, they were also called blanking presses, medal presses ect.
in the ornament trades.
And it is true about American's,Englishman ect nomenclature for some items. Sort of like the same church different pew.
the fly press comes in two main styles the H frame and a C frame or goose neck type.
Then we can get into the hammers which also can be used to stamp or impress coinage.
No that i have made you a hopeless confused mass on the floor in a semi fetal position [Beer]
I will let you ponder the question that comes to mind? Why me!:)
:)


Thanks for clearing that up, PT. I am always impressed with your knowledge of metalworking tools. [Beer]

#17 bill h

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Posted 18 September 2008 - 12:40 PM

Lets wake this thread back up.

Ok hello all. Nice to see this topic up and at em. Glen, I have these badge dies as you have seen and am looking at starting to make them in house. I will not need to blank the badges, but will just need to emboss the copper. It is (0) hardness 1/8-.145 thick copper. I have 4x4" tool steel (male, female)dies currently they have been pressed with an old coining press approx 65ton. The presses are old mechanicals,and after seeing the three guys at the place were these are from with missing fingers, I am not to possitive this is the direction I would like to go. I can get a 65-100 air clutch press with all the light curtains and such, but would like to stay away from the costs. iven on the 65ton that they where stamping these with they stated they had to hit them 6-7 times to catch all the details. What might be a diverse press/hammer etc. that would fit good in an artist shop to do the same type of thing?

I do have licence plates and other things, that are just embossed thin alloy aluminum,and brass, for machine plates etc,and am currently making a set of die shoes to use my 50 ton iron worker to do them.

Just looking for ideas.

Bill

#18 Lughaid

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Posted 08 December 2009 - 05:57 PM

I ran a manual stamping hammer for 10 years on the rennaissance faire circuits. We used a 125 pound hammer in a 12 foot frame for a drop of 9 feet or so. You had to hand crank the rope to pull up the hammer, lock the crank, then step away from the die to pull the release pin.

We used 1 inch diameter dies in a die holder to stamp the top and bottom. Mostly used 1/10th inch thick bronze slugs, although we also did sterling silver the same size, and 24K gold as well. Some of the heavier designs needed 2 or 3 strikes.

We made our dies in house, sculpting the master at 6 inches in diameter, then cutting the die with a 6 to 1 reduction using a Deckel pantographic mill. Made our dies with D2 steel, hardened and heat treated, then polished with diamond grit. Later technology advances made it easier to replace dies. We'd use the master die from the shop to stamp a couple of copper tools and use them to edm a new die blank.

Had a lot of fun with the setup. Best part was having forearms like Popeye from doing 200 or 300 reps a day at 125 pounds. 
There were other folks on the circuit using a Coining press. Much like a blacksmith's flypress but with a much slower screw for higher pressure.

#19 bartelfitzneel

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Posted 12 March 2010 - 02:11 PM

I make medieval style coins. I've had pretty good succes using a hammer (6#) striking coins up to 1" in diameter. The dies are all hand cut with punches and graver. Out of 1018 or 8620 depending on how long I want the die to last.
I'm not sure how to put pictures in these posts so here's some links:
http://www.bsaxton.c...s/stephaill.jpg
http://www.bsaxton.c...es/coinsobs.jpg
http://www.bsaxton.c...es/coinsrev.jpg

#20 ShawnM

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Posted 12 March 2010 - 03:37 PM

I make medieval style coins. I've had pretty good succes using a hammer (6#) striking coins up to 1" in diameter. The dies are all hand cut with punches and graver. Out of 1018 or 8620 depending on how long I want the die to last.
I'm not sure how to put pictures in these posts so here's some links:
http://www.bsaxton.c...s/stephaill.jpg
http://www.bsaxton.c...es/coinsobs.jpg
http://www.bsaxton.c...es/coinsrev.jpg


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