I have my K40 plus in my shed but it is too cold to use it there right now. I could move it to my office space but in that case I would need a smoke extractor. Does anyone have experience with the cheaper models like, for example, the Omtech ones:
Would that do the trick for the occasional laser project? Or is it bad?
Occasional laser project is what I did with my iCube, which has a carbon filter. It did not take much burning to get the smoky smell.
I tried making a carbon filter with a 12"x12" box and about 3 pounds of activated charcoal. Never satisfied with that either.
I finally went to ducted vent with inline fan through a board in the window. Laser is in an enclosure.
One last thought… Are replacement filters available and at what cost?
It is exactly my experience, too, I have built the most fancy activated coal filter … After less than a week of use, it was stopped working, although I have had 2 pre -filters mounted. The worst is acrylic and mdf. Fortunately, I have a little distance from the neighbor, so they are not bothered with my “direct discharge” of the evaporations.
I have a good working system in my shed with a strong fan to the outside but it’s just too cold now, that’s why I am looking for a solution in the office part of the house.
I am sure any workable solution will require an enclosure.
My K40+ is a closed system…
This is the way.
I have that, in my shed… A hole in the outside wall with a strong fan. But the question was if a cheaper smoke extractor would also work. I can’t open a window in my office space, we have a closed ventilation system.
That is also an option, but I just wanted to know if a cheaper smoke axtractor, like the example in the first post, would also work or if anyone had experience with one of those…
I apologize for my ignorance, but I’m not quite sure what you mean by “closed ventilation system”. I have my diode laser in my office in the house (an air-conditioned space). It’s in an enclosure which is vented out of a nearby window. The inline fan is set to a speed that keeps the fumes to a bare minimum (if the wife’s not complaining then I’m doing something right). It is true that I am venting some of my air-conditioned air to the outside, but I’m also not running it for hours and hours at a time. That’s when I fire up the CO2 laser in my workshop, which is set up the exact same way (I run a mini-split out there). There is some cost to venting cool or warm air to the outside, but for me it’s negligible. In the end we come back around to what does a “closed ventilation system” mean.
(“This is the way” is from the TV show “The Mandalorian” and was my way of saying that I agreed with what MikeyH said).
This is how my enclosure is vented.
I knew that. I am waiting for the series to start back up!
Ah, ok, you have a diode laser, I was referring to a CO2 laser. Pretty good setup by the way! 
I also have a 60W CO2 laser, but it was too big for my office. I have the same setup for it in my air-conditioned workshop, where the exhaust from the inline fan is vented out of a nearby window. The S.O. gave me the choice of one or the other, but not both 
.
What we need is a cheap air-to-air heat exchanger.
(emphasis mine)
Well, I mean, compared to my various lasers, an ERV (Energy Recovery Ventilator) isn’t that expensive. Of course, I currently have three exhausts plumbed through the wall from my various laser/CNC cabinets, and I’m often using two or three at a time.
I suppose I could add one larger return-air plenum and rig three ERVs, but so far I’ve just been considering a bit of conditioned air loss to be part of the cost of running my machines. I probably should at least add a baffled air inlet to the front of the shop (opposite end, 30’ away from the exhausts) so I don’t end up with too much negative pressure holding the door closed when everything’s running. 
I have the smoke extractor as you are considering. I purchased it when I first got my laser, naively assuming that this would allow me to run my laser in my office studio without needing to vent outside the building.
It is totally insufficient. I can get away with doing something like a business card or a wallet. But I am left putting off all my significant projects until I can relocate the laser workspace to a garage later this year.
Same here. I’ve intentionally not watched the last episode; I’m waiting until it starts back up again.
I feel the same way, and I live in Florida! The cost of a kilowatt hour around here is fairly low, and I cover the exhaust ports (at the window) when I’m not using them. My plan is to implement the “Ignorance Is Bliss” protocol and call it a day.
Baton Rouge, here. It’s not so much the temperature as it is dehumidifying the incoming air. I have a mini-split heat pump for my shop, but I also keep a dehumidifier in there to keep things properly dry.
I actually had an interesting discovery the other day when I was running just the fiber laser. Started getting an aroma reminiscent of the CO2, and after a bit I realized make-up air was backflowing through the CO2 venting. (I opened another vent, and I’ve got air gates to install on all the machine exhausts.)
