Exhaust Filtration System Requirements for Suburban Use

[bam (Ben M)]

Hi all, I’ve not had much joy with a search so starting a new post.

I’m looking at getting a laser primarily for cutting nylon fabric. I’m working out of my home so weary of gassing my family or neighbours even if running the exhaust outside. Is there anything to be concerned about or should I be looking at some sort of filtration system for the exhaust?

Thanks

[thx]

My laser is in an attached garage, and houses here are packed close together.

I removed the built-in fan and put a high-power extractor at the side of the house in a box, 30’ away from the laser. The extractor pushes the exhaust up a vent pipe about 12’ high and shoots it into the air well above head level. There are no opening windows on this side of the houses which is also good because this thing is loud! Ideally though the exhaust should be vented above the roof line, chimney height.

It’s important to put the extractor outside because any place there are fumes along the vent piping will be under vacuum, including inside the laser cutter. Leaks will suck air into the pipes. Otherwise the vent pipes will be under pressure and spew fumes into the room. This is probably the most significant thing you can do to eliminate smoke and smell from laser cutting. I cut tonnes and MDF and lots of acrylic and the garage doesn’t smell at all.

Outside you can only catch a faint whiff if you’re standing near the exhaust vent and the wind is blowing the exhaust towards you, even when cutting acrylic. MDF and plywood gives off a bit of pale blue smoke, but you can only see it if you’re looking for it and it completely dissipates a foot from the outlet.

I do most of the high-volume cutting late morning to early afternoon when nobody is around, but that’s mostly because of the noise. I will eventually make a sound-proof box (based on generator boxes). The extractor is controlled with a $20 15A remote power switch. The keyfob for it is at the laser.

I had a backup plan of building a carbon filter box, but that won’t be necessary now. I also bought a high-volume ozone generator with the idea of injecting ozone into the exhaust right after the laser, but the ozone smell is worse than acrylic (not to mention more damaging).

So to answer your question start with an outdoor extractor and check if it’s adequate (it probably will be if exhausted high enough). If not look into adding a carbon filter – there’s a few DIY ones on Instructables.

[MH1644 (Mike)]

Has anybody thought about exhausting through a radon abatement system? That would be ideal for my situation so far as exhaust location is concerned. I’m guessing that some sort of backflow device would be needed to prevent the exhaust from being dumped backward under the basement floor…

[bam (Ben M)]

Thanks guys. I’ll suss out the external exhaust/neg pressure set up.