Hello everyone. I have heard over and over that I should forge my ingots. I understand why but how do I forge them? Hit them with a hammer, anneal then roll? Is there a certain type of hammer to use, sledge (polished face of course), planishing hammer, ball peen hammer, heck I have even heard to forge with cross peens. What is the right way to forge ingots and with what sort of hammer?
Hi.
I pour ingots and make them into stock almost every day. Colleagues always recommended to forge ingots prior
to rolling but I never did. The results were fine but for some reason I started forging them first and the difference in ease and smoothness of rolling was immediately noticeable. So now I always forge.
Flat/ sheet ingots I forge with a small sledge or a large plannishing hammer or a nice big ball peen. I use the flat or slightly domed side. Forge them evenly on an anvil. Wire/rod ingots I forge with the same hammer forging along the long axis and then flipping it 90 degrees and forging that long axis. I only forge one face at a time relying on the anvil to move the metal on the bottom face, although it might be better to forge all four faces. I try to keep the square cross section fairly true and then roll through the square wire rollers.
I never anneal at this point and in fact don’t really anneal until I’ve reduced the mass by about 50 percent. I never anneal rotely (x amount of passes and then anneal) but I feel what the metal is doing. And I observe the edges for cracks.
A friend recently observed that he forged flat sterling ingots extensively and then uses the mill as the final refiner, perfecting the sheet.
I hope that helps.
Andy
Please excuse any typos-- curse my clumsy digits…
After pouring, but prior to forging, I remove any resin and then go over the entire ingot removing any little pointy areas, seam flashing and other irregularities. If there is a sharp divot, I file or grind them dull with an abrasive wheel. Then I lightly sand the entire surface. I do most of these operations on a 6" 220 grit expanding sanding wheel. I then forge with a rounded chisel shaped hammer on all sides trying to duplicate in forging the shape that I will eventually be rolling. Anneal and roll. Roll always in the same direction until you anneal next. I maintain this orientation by putting a small sharpie mark on a surface that doesn’t come into contact with the rollers, usually an edge. The mark will allow me to remember the orientation to the rollers. Anneal often. If a feather or burr appears, file or grind it out unless it is in an area that you won’t be using. Lots of fun, and if you screw it up, do it over. I am about to make and roll some 80/20 sheet for a reticulation project. There is a lot of very technical information in the archives about rolling. Go to the end of the article for the what to do and not why summary. Good luck…Rob
I think that we can anneal too often. Even when I am taper forging (actually step rolling) nickel white gold from an ingot to a long taper for a ring, maybe a 5 x 2 mm x-section down to a 2mm round, I anneal maybe once. My understanding is that a certain amount of cold working is required before proper sneaking can take place. (Jim Binnion is the voice of experience here.) I treat rose gold, palladium whites, yellow goods and sterling the same. The only difference is that when I anneal nickel white gold I quench it denatured alcohol when it has cooled to black heat. This arrests crystal/grain growth without shocking the metal. At least that’s my understanding.
I also don’t spend so much time going over the initial ingot for imperfections. But at the end if the day, if what you are doing works, it works.
Take care.
Andy — writing from Sicily. I just had to say it!
Please excuse any typos-- curse my clumsy digits…
Thank you for the input! Previously I have used a sledge with polished faces. It seems to work great! Is there any reason to use another sort of hammer?
No! if whatever you are doing works for you, keep doing it. I will do the same…Rob
I follow the same series of steps as do most of us. The only addition to my process is in between annealing, pickling, forging then rolling, each time; I wash the work in very hot water with Dawn dish soap and a scrub away the dull surface with a brass brush or bronze wool. I forge with a cross-peen hammer driving the hammer in the direction I will roll the material through the mill. I always roll in the same direction but I will swap bottom to top often. I have found no reason not to and I do that because it seems the right thing to do.
Don Meixner
Sure. As I wrote, if it works, it works. My reason for stating that I approach it a little differently is simply because I find it useful to remember that there are many different ways to achieve the same goal. I’ve also learned over the years to every now and then question the habits that I’ve developed.
A
Please excuse any typos-- curse my clumsy digits…