My fume vent uses a standard furnace filter placed over a box made of 2”x 2”frame and 1/4” plywood. The exhaust fan is a commercial product – a fan inside a section of 6” vent pipe – wired through a fan reostat switch to a regular electric cord. It works very well, and cost about $65 in materials

Aluminum extrusions by Brenner Industries made to anchor RV awnings works very well as a picture hanging system. There is a 3/8” mating rod which easily slips down the track for the awning. Brenner will cut 12' material lengths into 8' and 4' sections for UPS shipping. I cut the rod into 1”, 2” and 3” pieces, and had a machinists center drill these pieces to pass picture hanging wire through the center. Using multiple sections, or double hanging hooks, I have suspended a 5' x 9' framed painting which was pretty heavy. This system cost $1.50 a lineal foot; cheap relative to any gallery system. The photos show the aluminum, but oak quarter round was put over the aluminum. The remaining track is barely visible. Any other type of molding could be used.