Glowforge ported outside (pics) however room STINKS?

So my glowforge is ported out my windows as seen in the pic below.

  1. During cutting its not bad, if you stand in front of it you cannot smell anything. However weirdly you can smell if you stand where i took the second picture on the angle. You can also smell if you stand by the window on the left. Not sure why thats happening?

  2. When im done cutting the acrylic smell become overwhelming. This is a big room, i have another room attached, you can smell it there. My room is down a long hallway, I opened my door and everyone could smell in the hallway etc.

It is extremely disruptive and wont work in my school unless im able to cut down on the small. This was all from one 12" x 12" square of acrylic…

In desperate need of help. I bought a 4" in-line air filter thats shipping, cant imagine that it could make that much difference, maybe im wrong.



Did you trim the vent hose? it seems like a very short run showing in your first image and much longer in the second?


Nope, the hose is just out the window more in the 2nd

so 90 degrees up to the window then 180 degrees back to straight down through the window?

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what is the cardboard for? is that what’s blocking the open window at the bottom from the open air?

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Yes it also has a more enclosed carboard that fits to close the window, there was a small 3" gap that remained so i was putting boards in front to dampen the cold / light.

If the hose is out the window, and the window gap is blocked with the cardboard, you’re going to get a lot of odor coming back in through the gaps.

Figure out a way to put a board with weatherstripping in that window… or some other way to SEAL your exhaust. If it isn’t sealed, you’re going to have odor. It’s that simple.

I would also remove the inline filter you mentioned. With a sealed exhaust system, you won’t need it… it might just make things worse by restricting flow.


Yes sort of, more rounded than 90

Couple a suggestions. Make sure there is no ‘kinks’ in the flex tube. (hard 90 degree bents) this will block the air flow a bit. The other is rising the glowforge a bit.

For example,


(I KNOW I have images of the bottom of the machine, But I could not find them. So I am going use the CAD model as a stand-in.)

The area in blue is the intake for the machine. There are two long ‘feet’ that stratels the intake.
For a local makerspace that was having exhaust issues, I made a small ‘stand’ or ‘lift’ to give more clearance for the intake to pull in more air. And this works. The side effect is the machine will get louder. But it will work better with the ultra short exhaust run.

If you use the method, Its super duper important that the frame that unit sits on is level and equal height wise from the surface its on. i.e. if one side is 1" from the surface to the top of the frame, that measurement needs to be constant around the frame. Any wonkiness height wise will screw with the lid alignment.


OK. Looks like a classroom. So, that implies a commercial level of HVAC/Ventilation of some sort.

  1. There will be smell. It is unavoidable. The edges of a cut piece have a smell, for example, for long after the cut.

But the stench can be mitigated.

Things to check:

  1. The window needs to be FULLY SEALED. All the way around. Every last crack. Sticking a piece of wood in front of a crack isn’t going to help.

  2. The building may be negatively pressurized or there may be a cross draft that makes your art room suck air in thru whatever cracks it can. See (1), but you’ll need to make sure all windows in the room are sealed.

  3. Make sure there are no air inlet vents on the outside in that area. Also make sure any surrounding rooms don’t have windows that are cracked/open.

  4. If you using an air booster, make sure the housing of the booster is sealed. Make sure the hose is sealed. Make sure there aren’t pin holes (common with that style of hose). My booster was not sealed, for example.

  5. If using a booster, it should be at the far end of the hose; likely at the hole to the outside world. And it should be just north of 200CFM or so. You shouldn’t need a ton of vent hose outside the building. If your room isn’t sealed well enough to keep fumes out at the window, you’re going to get fumes depending on the whims of the winds.

  6. Run the booster for a few minutes (at the least) after the cutting operation to remove residual smell. It helps. But see 0).

  7. If you really want to mitigate stench, run a pipe vertically up the outside of the building with another booster and vent above the roofline.

  8. If you really really really want to mitigate stench, consider fume hood type solution with a second vent booster.

I’ve done through 6 and it isn’t too bad these days (save for when I open the machine after a cutting session without waiting for the vent to draw of residuals long enough because immediate gratification needed, thanks :slight_smile: ).

I’m seriously considering 7 because my side yard gets stinky and, depending on winds, the stench comes in the kitchen or the garage.

And I’m toying with 8 if I redesign my shop.


this, this, and more this.

if you need to be able to disconnect the GF, you’re better off leaving the adapter in the window and using a cap or blast gate to block the hole where you disconnect the hose. but any hole/gap you have anywhere in your exhaust system (which includes around the window block) will allow odors to enter the room.


so it sounds to me like you are over the 180 degrees of turns(2 90 degree bends) glow forge wants their duct limited to. you may be getting back pressure. There are some threads you can search for about inline booster fans.

Thanks for the suggestions @GrooveStranger, @bbum and @ihermit2 !

@cooperl, could you please try these suggestions and let us know how it goes?

one thing I did… NO pictures as it was a hack job.

I have a piece of plywood that has TWO dryer vents in it. ONE to the glowforge, and 1 goes to a 150cfm fan that just helps create negative pressure in the room where Beamer sits. keeps the smell from getting picked up by the air return. luckily the upstairs has it’s on system. but whenever I go into the office it does smell like burnt wood.

I did several acrylic items for Christmas. before I had the extra fan it would stink for a bit. now it is minimal.

Wood-- campfire esque. Annoying. Gets old. Sucks if you’re allergic to smoke (as I am).

Acrylic-- dammit! Who opened a nail salon in my craft room?!



I used one of these in my window. Works great. However, as others have mentioned, there will always be a smell. Some smells permeate more than others. Some smell better than others. Some smells linger more than others. But you should expect some odor.

I did this

the key piece is the Blue Whale in the bottom of the photo that removes all smoke, smells, and dust from the room very quickly, even popcorn smell does not get past the room.


As others have said, you will need to make sure the smoke isn’t coming back in through your window. You have to seal it completely! Any small gap and it will seep through.
You also have to remember that the cut parts and scrap will still smell, as noted earlier. This is the main contributor to the smell in my experience.
I have an air purifier that I run while and after cutting that eliminates the smell within a few hours, even with large acrylic jobs. Wood jobs are gone in half an hour or so.

hmm any links to big ones?

Windows are like 52" wide hahaha.

Is this too sharp of a turn coming directly out of the unit? Goes right out the window straight after. However I am very limited on space on this counter, thats about all i have.