Homebrew PCBs

Hi,

I just bought a Dremel Table Saw 580 (4" blade) on eBay. While waiting for delivery, I ask...

Can anyone recommend a proper blade pitch for cutting PCB fiberglass boards? Should I get different pitches for rough and final cuts?

I've heard that fiberglass causes a lot of wear on saw blades. Can anyone estimate how many boards a blade can cut before replacement? Should I buy a backup blade right away?

I also plan to use it to cut aluminum up to 1/8" thick for chassis work. Can someone recommend a good blade pitch for that task?

Finally. since this is my first circular saw, I've looked for online tutorials on safe and efficient operation. All I found were for 10" crcular saws cutting wood. Does anyone know of a tutorial for little saws cutting metal and fiberglass?

Thanks,
Jim