Richard Clements wrote in message ...
the concept looks easy enough, my thought was take a couple of high
filtration ....

There are pretty good plans in the book Controlling Dust In The
Workshop© by Rick Peters. I built one with a three speed 1/3 hp blower
motor with squirrel cage. (the plans call for a 1/15hp motor)
Therefore, everything had to be upsized to fit the blower housing
inside. Fortunately, the filters cost the same irregardless of size.

Furthermore, there was a discussion was going about switching the
different speeds about a month or so ago,. Someone suggested a on/off
switch and two three-way switches. Thats the way I went and it works
very well.