Silver Press Size

When she retires, my wife wants to set up a jewelery making business. One of the items she hopes to offer is custom tie chains. She would
like to be able to make the bar that sits over the shirt button and supports the end of the chain. We were thinking we could make it by bending some hard-drawn silver wire over pin mandrels and then flattening the shaped wire to work harden it and give it additional stiffness by changing it to a rectangular cross section.
Because of the shape of the piece and the button loop, I don't think a roller would work. So the question is: how big of a hydraulic press can I justify to enable her to flatten silver? The finished piece would have a surface area of about 0.6 square inches, and a thickness of 0.315 inches (more or lesss depending on the stiffness of the finished product). For small runs, I realize I could probably have better control over the thickness with a screw press, but I was planning on milling out a recess in a block of steel to control the thickness using a hydraulic press. (Besides, I have more uses in my shop for a good hydraulic press.) HF has a 20-ton press on sale at the store for $170. overkil?l - yes, justifiable? - ??!
Thanks, Ed Bailen
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One shop I worked in had an electric driven hydralic 100 tom press. It did a real nice job of flattening out pennies to twice their original size. :-)
Ed Bailen wrote:

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James P Crombie
Slemon Park, PEI
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On Mon, 03 May 2004 22:45:46 -0300, Machineman

How about matched plates, the lower one with a cavity of the desired shape, the upper being flat; and the traditional BFH. Gerry :-)} London, Canada
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wrote:

That's a good idea. 20 tons isn't all that much when it comes to making metal flow , which is what flattening basically is. The idea of a hydraulic press for something that can easily be done with a hammer may seem like overkill, but may not actually be. It's hard to say what tonnage would be required for that operation without seeing it and experimenting. 50 tons would do it (^:# I bet . 20 would likely be enough . But I was surprised at how less effective a 20 or 25 ton press was for this sort of thing than I thought it would be. These days I mostly limit my press flattening to cute demonstrations for friends and visitors , and show what 50 tons does to a soda can , or cigarette, or pine board.... whatever's handy !. Dar www.sheltech.net
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What about a drop hammer or where you looking for something small. As you are probably using small wire the hammer weight and guide frame would not need to be very big and the force exerted is controlled by the drop height. If you can get a small flypress they are quite versatile and you get good feel but although these are common in the UK I understand they are not in the US.
Gerald Miller wrote:

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If I understand correctly you need to press a wire about 3 or 4 inches long from round to rectangular. Someone here probably has the right answer. But if you have to make a die anyway, why not make the die first and then try using a vise first to get an idea of what it really takes. I suspect you could use a three ton hydraulic jack. But one test is worth three opinions.
Dan

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1. That's a fairly standard finding, available in gold for sure, but probably in silver also. Have you looked in the catalogs of findings suppliers.
2. Generally speaking, you don't do your own stamping unless you intend to go into the stamping business or unless you a huge manufacturer. If you can't buy a suitable, ready-made, finding, you pay to have a set of dies created and then have the stuff stamped out by a stamping company for you. I don't know how much the dies will cost -- but probably several hundred dollars. Once you have the dies, you pay a modest set-up fee and then stamp out a few hundred or a few thousand pieces. What you describe probably takes about a second or two. Less with an automatic feed system.
3. Die making is a ticklish business -- hence the top machinists are called "tool and die makers." Don't expect to get it right the first time out. Stamping is also not trivial and involves lots of know-how. These are the sort of things you leave to professionals. In my day, in the New York City jewelry district (and also today) all but the largest manufacturers (mostly for costume and low end jewelry) sent their stampings out to shop that did only that sort of work. A handful of stamping companies handled the entire industry.
Boris
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Boris Beizer Ph.D. Seminars and Consulting
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