Great forum---lots of great info---thanks! I am working on a home project, and maybe you can help me. I have a small piece of copper pipe (its an end cap for a 1 inch copper water pipe). I want to reduce the weight of the cap by approximatly 1/2. (as bought from the store it weighs about 1.5 ounces---I would like to get the weight down below 5/8 of an ounce) I can accomplish this mechanically by milling the piece with a rotary file, but it takes alot of time---I am looking for an easier way. I know in the aircraft industry, they sometimes use chemical milling to form parts to the desired shape (they dip parts into a solution, and it dissolves part of the metal until it is at the desired thickness) Any ideas? Anything practical to try at home (without burning down the house?!) Any suggestions will be appreciated!