Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

Hi All,
Just a quick note! With the Think and Tinker Bits you can
get .0004" to .0006" of feedrate for every revolution of your spindle
motor. So if you have a machine that has a top speed of 10,000 rpms
you can only use a 6" feedrate. That is pushing the tool hard. A 5"
per minute rate would result in longer tool life. Very simple PCBoards
2" by 2" work well no matter what you do. Problems show up on boards
4" X 6" or larger with 200 inches or more of traces.
I was told by someone he was using a cheap air powered grinder
to make circuit boards. With 50,000 rpm he claimed a speed of 20" per
minute. A few weeks later he contacted me when he tried milling a
real pcboard. Power supply circuits are a snap! The problems show up
when making boards that have small ICs.

John