Check out my build.
I also used a 600 Cfm fan out of a kitchenaid hood...and am using 20x20 furnace filters slid into dado like structure.
My first filter is a 2 dollar filter....the second filter Is a 5 dollar filter...and the final filter is a 20 dollar high end furnace filter. I change the first stage every month or so...the second stage is still original....but probably getting close to needing replacement. The final stage is as white as the day I put it in....
I placed clear packing tape over the output and ran the filter for a few hours while sanding and the output had virtually zero dust in it.....
Total cost for filters...under 30 bucks
http://www.woodworkingtalk.com/f32/home-made-air-filter-45667/
And very cheap maintenance on the first filter.
I also used a 600 Cfm fan out of a kitchenaid hood...and am using 20x20 furnace filters slid into dado like structure.
My first filter is a 2 dollar filter....the second filter Is a 5 dollar filter...and the final filter is a 20 dollar high end furnace filter. I change the first stage every month or so...the second stage is still original....but probably getting close to needing replacement. The final stage is as white as the day I put it in....
I placed clear packing tape over the output and ran the filter for a few hours while sanding and the output had virtually zero dust in it.....
Total cost for filters...under 30 bucks
http://www.woodworkingtalk.com/f32/home-made-air-filter-45667/
And very cheap maintenance on the first filter.