Small Shop Air Filter

I wish I had this when I first started woodworking.
I’ve called numerous hvac contractors and none of them would sell me an old blower.
No luck with the junk yard either.
Took me 3 days to come up with a design that I was happy with.
There are so many ways to make this and I decided to make it small and easy for the
blower so I made the intake right where the turbine is and placed 2 filters there. One filter for the exhaust.

My garage is about 19’L x 17’W x 8’H. The ridge tops off at 12.5’ (H + 4.5).
The volume for the bottom rectangular part is 19×17 x 8 =2584.
The top triangular part is 1/2×19 x 4.5×17 =726.75. The 2 added yields a volume of 3310.75.
To circulate the air every 5 mins(3310.75/5) I need a 662.15 cfm blower. For 10 mins it’ll be 331.08 cfm.
I went with every 7 mins at 473 cfm which was dictated by my budget.

All the wood materials are left over pieces: 3/4 and 1/2 mdf, plywood and strips from 2×4.
Dayton 463 cfm blower $103. 10 cfm off is not bad I hope. You can find tons of fans if
you do a search for hydroponics and look for their fan section.
I heard Dayton’s were built well so that’s what I got.
15 ft power chord from Lowes around $7
Some spare bolts/nuts and wing nuts.
Exhaust: 12×12 x 1 pleated filter $4 from Ace Hardware. Didn’t find any at HomeDepot or Lowes.
Intake: 12×24 x 1 fiberglass filter $ 3 which I cut in half.

It’s a box that is almost 15 in all around.
It’s not heavy so I can take it anywhere. Might locate this atop a tall mobile cabinet.
The filters are real snug and not loose in their slots.
Placed weatherstripping all around the bottom of the lid.
The wing nuts are a little time consuming to remove/install but I like the tight fit.
The fiberglass filter doesn’t filter very well, the gaps are a little too wide for me.
A 12 hr timer would be great but later.
I have some left over X10 to control it remotely but haven’t hooked it up yet.
May paint it but don’t see the need for now.
Turned on the Ridgid vac to get some dust airborn.
Closed the garage and after an hour you’ll see the dust from the last picture.
Fun project.