Spears Posted May 30, 2012 Share Posted May 30, 2012 The following shows the results of an experiment in making medallions from sheet metal cutouts by hammering red hot metal using the cutouts as a mold. Blanks were cut from 1/4” thick hot rolled steel plate and then soaked in vinegar for scale removal followed by scotch bright clean up. A 5/32" diameter rod was tack welded to the edge of the blanks for holding in place inside the fixture. The fixture was constructed from the same material as the blanks so the sheet metal cut out would make the red hot blank stick up out of the fixture the amount of its thickness and could be hammered flush on the flat die of my power hammer. Clearance was allowed for thermal expansion of the heated blank for fitting into the fixture. Hammered flush the blank packed out nicely and with using the rod and thumb screws the fixture could be lifted off and the medallion tapped out while hot. This turned out to be a beautiful process made efficient only by CNC laser cutting the blanks and sheet metal. Otherwise this process would have been quite a time taker. The sheet metal cutouts of high detail were destroyed in 1-3 medallions and the more simple shapes like the Alabama “A” could go 4-6 before discard. Sports emblems aren’t my specialty, but for this multiple part production experiment became highly desired giveaways. Medallions with my logo may take the place of a touch mark for some of my sculptures and forged items. Enjoy, Spears. Quote Link to comment Share on other sites More sharing options...
ironwolfforgeca Posted May 30, 2012 Share Posted May 30, 2012 NICE JOB !! Spears ? Would a thicker cut out pattern stand up longer ? also have you tried this in a press set up ? I really like the Idea ! Thanks for posting Quote Link to comment Share on other sites More sharing options...
bigfootnampa Posted May 30, 2012 Share Posted May 30, 2012 1/4" seems pretty heavy for medallions... what if you used 1/8" plate? Your patterns might last longer being exposed to less heat that way. Quote Link to comment Share on other sites More sharing options...
Spears Posted May 30, 2012 Author Share Posted May 30, 2012 Big foot, I more or less end up playing around with materials I can readily get my hands on. I wouldn’t have minded using material a little thinner. Then again, with my luck someone would probably try to jam it in a vending machine. LOL. Ironwolf, those are extremely good questions. I’m not an expert in press forging but I would tend to think a press would work better on thick bars that can retain heat a bit longer than a small disk of material. Unless one quick squish works better than 4 quick blows. If I had a press I would try it. The mass of that puck (1.48” dia .25 thick) doesn’t stay hot for long. My hammer is a Robertson air hammer with 115 psi, 2.5” diameter Hydraulic cylinder, 700lb anvil block welded to a 400lb base plate. I can get 4-6 strikes in ~ 2 seconds ~8” stroke and the puck is packed out and turned grey around the outer. A decent load of abuse in a short amount of time. The disk cutout was .045” thick 304 Stainless steel and the sharp corners which bring that fine detail probably get rounded over from combination both impact and heat. I think that result is inevitable. If packed out to heavy both the materials were prone to sticking which when pried apart becomes more prone to destroying the mold cutout. I did find as thin and the sheet metal is, I could pack it down quickly to bottom out so the top of the protruding pattern has flat spots from the lower die, but not on all of them. Thicker sheet metal might prevent this, but it really doesn’t look bad. The disk also becomes larger and after 2 or 3 uses and would need filing to fit into the fixture again. Pretty much disposable patterns. Thanks for viewing and I will post more pictures if I do more. Spears. Quote Link to comment Share on other sites More sharing options...
chyancarrek Posted May 30, 2012 Share Posted May 30, 2012 Nicely done Spears. I really like the way you've got them set up for consistent repeats. I started making something similar about 10 years ago as a way to get rid of all those bits and pieces that you just know you're going to do "something" with. One heat in the air hammer to flatten them out, then a couple of whacks at yellow heat to imprint them. Wire brush and wax, then into a bowl for 5 bucks apiece. They're crude and primitive but kids love 'em! I call them "TouchStones" and when I was doing markets and shows, I'd have kids come by every week to see if I had any new patterns so they could add to their collections! They're also the #1 pick when we make up the little gift bags for our kid's birthday parties with their friends. The "lollipops" in the pics are my originals ( I used carbide bits in a Foredom to carve the design). I've got about 20 designs and they've held up really well over the years. I haven't had to remake any of them and I've got at least several hundred impressions on each one. Thanks for posting this and keep the pics coming . . . I'm thinking setting up something along the same lines would be a good way to go for a more refined version of what I'm doing now. Quote Link to comment Share on other sites More sharing options...
Spears Posted May 30, 2012 Author Share Posted May 30, 2012 That's awesome chyan... Hard tooling to hold up against make quantitiy 100's + Can't beat that inventory stocker !! Nothing worse than setting up a table somewhere and not having enough for folks to look at. Smaller items many times out do everything else at the show. Thanks for showing. Quote Link to comment Share on other sites More sharing options...
Frosty Posted May 30, 2012 Share Posted May 30, 2012 It's so great having creative folk to adopt and adapt from! Really nice stampings and no reason the tooling shouldn't last quite a while if the stock is hot enough. Have you tried bronze, brass, aluminum, etc.? Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
female_blacksmith Posted June 3, 2012 Share Posted June 3, 2012 I am envious of your ' big boys toys ' Spears and I really like the idea of using the sheet metal cutouts to create texture in a medallion form, and the fact you can pump them out in large nos. ( good ' bread and butter money ' ) I also really like your lollipops chyan.... The primitive look really appeals to me, they are such fun. Quote Link to comment Share on other sites More sharing options...
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