Window Vent for Laser Engraver Enclosure

thingiverse

My wife needed a way to route the toxic fumes from her laser engraver to the outdoors where it won't slowly poison her. She had purchased an enclosure for the machine and it came with an exhaust fan and a section of 3" hose. This was not quite long enough to reach a window and it didn't come with any way to interface with a window anyway, so I made two accessories for her: a 3" to 2½" coupler (to interface with standard dust collection hose) and this window vent.There are two parts to this vent:A tube/flange that attaches to a plywood board on one side and accepts a 2½" vacuum/dust collection hose on the other. This is the indoor portion.A nearly identical tube/flange that goes on the other side of the plywood. This is the outdoor portion and serves as an outlet for fumes. Where this piece differs from the other piece is that the top half of the tube has a capped upper half and a shorter bottom half, with the goal of preventing water from getting into the tube.The vent is installed in a board that was sized to fit vertically in a left-right slider window in her workshop.This vent is not louvered or flapped. I may add that at some point, but I will need to see how well the current design works before I make any changes.You should paint the outdoor fitting if you are using PLA. Paint the entire part, inside and out. Then sand it lightly and paint it again.You will need some sort of machine screw/washer/nut combination to attach and align these pieces. Alternatively, you could use wood screws, although you will need to offset the indoor and outdoor portions to avoid screw collision. I chose to use long M4 machine screws. If using larger diameter screws, you might need to enlarge the screw holes. Use washers in any case. Bonus points if you include some split washers. Don't overtighten.I installed the vent in a piece of ½" OSB, which I gave three coats of an exterior paint on both sides. I also caulked where the flanges contact the wood. Spacer blocks were added on the three window track sides to keep the panel from moving in and out.You will need to make a suitably-sized hole in your plywood/OSB. 2¼" should do it.½" thickness plywood should work fine. Thicker wood will require longer screws.You should sandwich a double layer of window screen material between the exterior flange and the plywood. This will help keep insects out of your workspace. Make the square the same size as the flange (89mm). I used stainless steel screen material for longevity.Lastly, I included a blast gate in between the hose and the inside of the vent. This connection is made using a 2½" rubber coupler and worm gear clamps. When not actively venting fumes from the laser engraver, the gate will be closed.This project was designed entirely by me in TinkerCAD. It is not based on any other designs.Apologies in advance for any typos.