Kind of a repost from
http://stevedgood.com/community/index.php?topic=4871.0 that I started a while back, but thought some of the newer people would find useful. My experience is cutting from Brass, Copper and Aluminum. Most of my aluminum I have cut is .050 PPW (pre-painted white on one side).
Blades I use: Jewelers Blades from Sloan's Woodshop (
http://www.sloanswoodshop.com/scroll_saw_blades.htm). Size 1-JW and 2-JW. Most things I found cut the best with the 1-JW because it is smaller and turns the corners better without binding. Saw is set at the lowest speed, which makes it kind of timely on thicker metals. Most alum I have cut is .050 inches. Make sure you tape both front and back (I just use masking tape) so it gives enough to lubricate the blade. You will definitely break blades, but at $12.00 per gross, they are cheap compared to wood blades. Can't push it much with those blades either or they will just break. It's weird, but you can hear the pitch of the blade change just before it breaks. I actually like cutting metals better since there really is no dust, but it makes a mess of the table and I usually have to clean it and rewax the table after doing it.
Note on the PPW Aluminum...Good thing about this is it comes with a protective plastic coating that you can spray on adhesive, stick the pattern on, cut it out and then peel the coating with pattern off very clean when done. I purchased it from a semi-trailer manufacturer, since they use it for the sides of trailers and have lots of scrap pieces.
Only other thing I can think of right off on metals is you will have to sand the backs of all (leaves little burs that come off rather quick) and on brass and copper, sand with very fine grit to get a good shine and then spray with clear coat. Otherwise, every time you touch with your finger, the oil in your hands will tarnish. Also will tarnish in general in very short time.
Thanks for reading...comments welcome!