I built a panel for my window and a properly sealed air venting path according to spec (only two bends, length within recommended tolerances). Then I spent about an hour cutting thick-ish black acrylic.
At first, it seemed the system was working fine. Could barely smell the acrylic. Then the cut was done, I waited until the fan stopped running, opened the Glowforge, and there was a lot more smell. By the time I’d cut for an hour (and opened another window far from the venting, to let in fresh air), both I and some other people in our workspace started feeling a bit woozy, and someone who walked in commented they could smell it all down the hall.
Clearly, something’s wrong. It’s fall here and getting cold, and the vent goes upwards, so I was wondering if what’s happening is there’s some atmospheric pressure pushing the air back down the vent as soon as the fan stops running. At least when you light a fire in a fireplace here during this season you have to heat the air first to push out an “air lock” so the smoke doesn’t come into the room instead of going out the chimney. Perhaps an extra fan in the pipe that would keep running even after the cut is done would fix this? Or could one somehow set the Glowforge fan to keep running for a bit after the job is done?
The other thing I was wondering is this: I have the Air Filter on order. How good is it going to be? Can I trust it to work in a workshop full of people without letting these fumes through?