I need to cut many small pieces of sheet metal (maximum finished dimensions roughly 1 by 2 feet). I‘m using copper and aluminum roof flashing, so it‘s not particularly thick.Up to present I‘ve been scoring the metal with a sharp box cutter/utility knife, then folding it to break the metal. I‘m not happy with how sharp and rough the resulting edges are though. It also dulls knife blades pretty fast.There‘s got to be a better way, I just don‘t know what it is. Any suggestions?
First of all I hope you are not using copper and aluminum together. I would be concerned about corosion between two dissimilar metals in a wet and potentially acid (rain) environment. You will notice that the aluminum is much thinner than the copper. For the copper you will need snips to get a good result. There are many types side cutters, straight cutters, curved right and left cutters there are even electric shears. The cutting will be slow (unless it is electric) but the result will be more polished. Where you have an exposed edge that you want to make look particulary good you will have to bend it back on itself and hammer it down. Aluminum flashing is different. Unless you are trying to make a curved cut or a shape I typically use a utility knife. The removable blades are more sturdy than the blades of a box cutter which typically uses single edge razor blades (they are shape and good for paper but dull quickly on metal) You can get the blades 100 to a pack and you will not go through them all. What you don't want to do is bend the metal to break it after you score it. This is what is giving you the sharp edge. Instead you want to rip it. For example suppose I had some 24 aluminum flashing that was 50' long. I needed a lot of 12 flashing. I would carefully score the entire 50' length at the 12mark. (Once is usually enough) Then I would go to one end and work the edges at the end until it cracks and becomes a cut. (like opening one of those pill packages) Once you have started the cut you push one end down and pull the other end up and it should rip on the line you have scored. Once again it you need a particularly beautiful edge you will have to bend it back on itself. If you are doing a lot of bending you will need a brake ( a device for bending metal. )
Tin snips? Sorry if I'm completely off-base here; I haven't been in a shop class since the eighties.
