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BillH
12-07-2003, 01:11 AM
Im just wondering, If a sheetmetal break or shear or roller is rated 18 or 22 guage mild steel, what is its rating for annealed copper? For right now, I would like a nice break for making some arch bar trucks for my 1" scale pennsy a3 locomotive. Later on, I would like to roll and shear some parts out of copper to make a copper boiler.
Just browsing the stuff enco and grizzly has.

Thrud
12-07-2003, 01:29 AM
Bill
Whatever the machine is rated for steel you should be able to nearly double for annealed copper. For light work such as models standard sheet metal gear is adequate for upto 14Ga. copper - maybe even 12Ga. and 10Ga. in shorter lengths. Copper is not terribly difficult to form with a pan brake and cuts easily with a guillotine shear with crisp edges on the blades.

jfsmith
12-07-2003, 01:31 AM
I have used mine on annealed copper up to 16 gauage with the ones that are sold by Grixxly and HF.

Copper that has been annealed is much easier to cut than copper that has work hardened.

Jerry

dvideo
12-07-2003, 04:54 AM
Copper brings back good memories. When I was about 4, I was "baby-sit" in a sheet metal shop. The old geezer who ran it (wish I knew him for longer) let me cut up copper sheets and make things. Mostly, I would beat the sheets into airplanes. Like you might make a paper airplane, now.... They flew something awful. But I made a lot of airplanes... :>

That would probably scare parents creepy today.... :<

--jerry

CCWKen
12-08-2003, 11:25 PM
If it is truely Copper and not Brass, you can double the capacity. If it is brass, you can add about 25% to the capacity. Bear in mind that many suppliers use different "guages" for mild steel and copper/brass sheet. Go by the measured thickness NOT guage.

DR
12-09-2003, 03:00 PM
Sometimes a flimsy machine might not do copper well, even though it might do steel. Shearing is a fracturing process, the fracture starts on both sides of the material and meets somewhere midway. Steel is easier sometimes to fracture than soft copper, so with copper the material may roll and wedge the blades apart rather than fracture (shear) like harder materials.

I demonstrated this to a friend recently. We were at an auction looking at a nice Pexto stomp shear. We tried a piece of 18ga steel with good results. Tried a piece of thinner copper and it just rolled over between the blades. The blade gap was too wide for the thin copper. In this case it would only be a matter of adjusting the gap and the machine would cut copper very well. But, a lesser machine might not have the adjustments and rigidity of the Pexto to make it a good machine for copper.

So the moral here is, try before you buy.

BillH
12-09-2003, 03:38 PM
Hmm, very good point. I more or less just need the break, to bend accurate angles repeatedly to make arch bars. Later on though, shears would be very nice.