My team is trying to make several complex parts out of acetal copolymer, but no one with a CO2 laser wants to cut it cause of fumes(needs direct outdoor venting). What are some good alternative plastics that are cuttable by a CO2 or diode laser , and vex legal. Any recommendations would be helpful.
My school uses 1/8" Delrin for all custom parts. We have a ventilation system, so I don’t really know how bad the fumes are, but it’s never good to breathe them in.
both release formaldehyde which is a big no no for my school’s indoor setup.
The CO2 laser is probably fully closed, has an inline booster fan in the 140 to 410 CFM range and thus can capture 90-99% of fumes. If the hose vents outside and is reasonably short (6 to 12 feet) and you keep the laser fan on for 30-60 seconds after the job is done, it should all be absolutely fine.
If the hose is leaky, the fan is weak, or you open the lid immediately, you can briefly hit the odor/irritation zone (~0.1–0.3 ppm for many people).
If you want to get technical, OSHA 8-hour PEL is 0.75 ppm; STEL is 2 ppm.
Been cutting Delrin on an XTool for 2+ years, if done right it is pretty safe.
We are unable. to vent outside, but we have HEPA and a activated carbon filter, + 4 other filters, Is this a safe setup?
Activated carbon filters do remove formaldehyde. HEPA does nothing for volatiles.
You would need to vent in a sealed space where the fan+filters pull from.
There are more variables to consider in this scenario.
Someone at the school that knows your setup should be able to do some calculations based on the equipment and space/geometry to make that determination.
Outside venting still safer and cheaper to implement 
In my schools new lab, our laser cutters are hooked up directly with the schools ventaliation system. however, in our old lab, what we did was create a custom window with a large hole in it and attached it to one of the windows of our lab. the hold would be connected to a tube that would run straight to the laser cutter. this whole process was quite cheap tbh