Tell us about yourself!
Great idea, depending on the size of the filter adding a little sheet foam inside and you have a manly beer coozie.
That is a neat trick / variation to the "toenail" fastening I've done many times in the past, as for all the ones that say using screws is better, I shy away from screws in framing due to the lack of shear strength (they tend to snap in a shear force) unless you're using screws designed to have shear strength equal or better than the nails you're framing with.
How to build an insanely bright LED flashlight!
Garden Tractor to Pickup Truck
The No-Weld Double-Barrel Smoker (and how to use it)