I posted a porpoise themed necklace I made a steel die for here some time ago. Today,my wife asked me to press out 4 more of them for her,so I got her to make some pictures as the process went along. I can't recall if I've ever made a photo essay of making an object.
The first picture shows the sawn out silver blanks being annealed for the first pressing. The camera refuses to show low red heat,somehow. It takes 3 pressings in all to form the coined necklace. The 2nd. picture shows the partially coined pieces being re annealed for the final pressing. I only have 50 tons of pressure,and that isn't a lot in the realm of coining. The image takes 2 pressings to come out complete.
The 3rd picture(sorry,they're out of order),shows the steel die and a blank,annealed,and pickled clean piece of silver ready to be assembled into the home made press. The silver is 16 gauge. At today's prices,that's about $20.00 worth.
The 4th. Picture shows a brass sheet that will be used to press the "fingerprint" pattern onto the back of the necklace. You can see the back of a piece pressed into the steel die. The brass sheet will be laid over it,and the fingerprint design squeezed on. We always have a pattern embossed on the back of our jewelry. It makes the piece more interesting on the back side,and makes a nice surprise when it is turned over.
The 5th. photo shows a porpoise that has been blacked after pressing,so the details show up better. It is difficult to see the school of playful little fishes in front of the dolphin,and the other details if the piece is not blacked a bit.
The 6th. Photo shows 4 coined dolphins. The die behind it is a heart shaped necklace or brooch die I made also.
The last image is me,bearing down on the jack handle as hard as I can with 242 pounds of weight. Red faced from the effort. You can see two fully hardened steel blocks over 1" thick each inside the press. The die and the silver are between them. The hardened steel surfaces are a must,as the die and the silver would sink into soft steel and damage,probably shatter the die. The die is pretty hard itself,being drawn to a medium brown color. So far it has not gone PING!! and shattered.My wife could not begin to press out this necklace. She weighs only 112 pounds. I have to strain to get the porpoise fully coined. It takes 75 tons of pressure to coin a quarter at the U.S. Mint,I believe.
I have a 100 ton Enerpac jack and its hydraulic cylinder and plan to make a more powerful press someday. This involves very heavy metal,though,much heavier than this press is. And,this shop is upstairs from mine. All press parts will have to be lugged up the stairs with my spinal stenosis. The 50 ton jack can warp the 3" thick top of the press here. I lay a piece of steel across its top. You can see the 3/8" square piece of precision ground stock laying there. When the top shows 1/32" of curve,I stop pumping,lest the top take a permanent warp.
The porpoise is still far from finished: My wife has to file down the margin and file in a deckled edge. She has to fine sand and polish the margin also. I left plenty of metal for her to do so. She has to make,and solder on 2 loops,and make up the chain and its clasp to suit the customer in length.
We tried casting the dolphin,as this process takes a good deal of time and effort. But,the casting just doesn't have the perfect crispness of a real coining. So,I guess we keep on coining them. I'm retired anyway,so she gets my labor for free.(Not really,it's part of our living).
The wooden "tree" is a holder I made to hold several different sets of needle files and die sinker's files. It's on a small lazy Susan for easy access. There is a thick sheet of urethane about the hardness of a rubber shoe heel (Shore 80 hardness). It is useful for putting behind objects I want to form,like the heart pendant. The brass thing seen there is the forming die to place behind the heart. Then,the heart is forced,face first into the urethane,"inflating" it. The urethane does not damage the delicate engraving and embossing on the heart. Sometimes I use a block of nylon to press into.
I don;'t know how those "Bonny Doon" 50 ton presses made out of square steel tubing hold together. My guess is the jewelers who use them,especially the women,can't really bear down on them hard enough to ruin the press. This solid steel one barely makes it. The threads in those large,hardened nuts shift sideways a bit!!