The air assist pump sits in the right rear of the OMTech laser’s main compartment:
Where it is, of course, exposed to all the usual dust / fragments / fumes / smoke generated by laser cutting & engraving, enhanced by my attention to getting good air flow over the platform. The picture shows the base plate in as-delivered condition, which it will never resemble ever again.
The problem: any crud in the air can clog the pump or contaminate the laser focus lens.
Four screws into threaded holes hold the pump to the base plate, secured with jam nuts on the outside.
The air inlet is a round fitting centered on the bottom of the pump housing:
You’ll note the out-of-focus crud scattered on the base plate.
The general idea is to drill a hole through the base plate, put a snorkel on the inlet, and have it inhale fresh, relatively clean, basement air from outside the cabinet. The trick will be not touching the base plate with anything solid, because the pump vibrates like crazy; its four squishy standoffs do a great job of isolating the tremors from the base screwed to the laser cabinet.
Having a few other things going on at the moment, I just laid two generous wads of cheesecloth where they can filter the bigger chunks out of the air stream:
The air flow meter says the pump still delivers 12 l/m to the nozzle, so the cheesecloth has no effect compared to four or five feet of 4 mm ID tubing.
A doodle summarizes the inlet fitting dimensions:
That looks like a 3D printed disk with a snout for a short air hose should do the trick, with a thin gasket sealing the disk to the fitting.
Now I can throw that piece of paper out …