Ever choked at the price of a small copper sheet from the local hardware store? I recently did and decided to do something I did years ago, to unroll a piece of copper pipe to make a sheet of copper.
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Step 1: Cutting the Copper Pipe
First cut a section of the pipe which is the length you want. This can be any reasonable amount, though I wouldn't go above what would result in a square sheet. To make a square sheet, multiply the diameter of the pipe by pi (3.14), then cut off that length of the pipe. A vise and hacksaw will do the job, although it'll be more likely to be square if you use a pipe cutter. The disadvantage of the pipe cutter is that it will result in an edge is slightly curled up. The disadvantage of the vise and hacksaw is that a steel vise may mar the surface of the pipe. That scratching will be in the part of the pipe that we don't use, but it could cause problems the next time we want to do a project.Then cut the pipe lengthwise with a vise and hacksaw. We want to unroll this, but the metal is too hard at this point.
Step 2: Anneal the Metal
The process of softening metal is called annealing, Basically, you heat the metal up to a certain temperature and then let it cool off. This can be anywhere between the time the copper is covered with a black oxide, up to the point where it is glowing dull red. My first choice for a heating device is the burner on a gas stove. The second is a propane torch, and the third is the burner on an electric stove. The gas stove and the propane torch will allow you to heat to a dull red glow, I used the electric stove, and while the copper didn't get red, a black oxide coating appeared on all of it. on it. When it has cooled off, a little pull on the copper will show that it's soft now.
Step 3: Forming the Copper Into a Sheet
The first thing I did when it had cooled enough was to unroll and flatten the copper with my fingers. It was a little uneven at spots, so I used a pair of pliers to help. Don't get too carried away, the copper will work-harden, and you'll have to anneal it again. Once the copper was flat, I used a file to get the edges clean and nice. Then I used 220 grit sandpaper to remove the oxide layer and shine it up some. For some projects, working up to a finer grade of sandpaper, then polishing could be used. I was using a piece of this as an electrical contact, I didn't worry too much about the finish, it was to be tinned with solder before use.
We're done now. Time for you to think of something made with copper!