New GF Plus - Smoke and smell inside house

Hello, just set up my GF yesterday and started to play with it today once I had my window vent set up. I am using my GF in the basement vented out of my egress window. I have the vent hose attached with the ring clamp to the GF, and taped to a vent cover that is installed in a window vent kit.

Using medium draftboard for all of the following tests…

My first attempt at doing the gift of good measure, I could really smell smoke inside the basement, so that is when I decided to tape everything up to see if there was any leakage in the vent system.

I re-ran the gift of good measure after that it didn’t seem to make much difference.

After that, I decided to remove the ‘insect screen’ from the vent cover to see if there was a loss of air flow issue from that.

I figured it was going to work well, so I tried cutting a small tabbed box to see how well the website made them for a tight fit…it was only a 3 minute cut, but the basement filled up with enough smoke that I thought the smoke detectors were going to go off…then the furnace transferred the smoke and smell throughout the entire house after that.

It doesn’t look like the smoke is coming out of the GF itself, I see nothing coming up out of the cracks of the lid or anything like that. I am wondering if the smoke and smell is being sucked back in through the window where there is a partial gap between the top and bottom window sections.

Has this happened to anyone else? Should I tape off every joint in the window and see if it happens again? Is there something else I should try?


That’s a distinct possibility. If you can realistically tape off the window, it’s worth a try People also find leaks around where the hose attaches to the Glowforge, and some have said there are pinholes in the hose itself if you hold it up to the light, although mine doesn’t have those.

I got a hand-me-down inline fan from my “little” brother @timjedwards, and that has dramatically cut down on smoke (and noise!) for me. If you do a search here on “inline fan” you’ll find lots of info, if that interests you. :wink:

Whatever you do, though, don’t tape up the cracks in the machine itself. It needs those for air to flow in through. And actually, the fact you’re not seeing smoke coming back out of those tells me your vent hose routing and fan are probably fine, so that’s a good sign. :slight_smile:


I would seal up any gaps and check the exhaust hose for holes, the gap you mentioned between the window sections sounds similar to the issue i had when i first setup my machine. I was able to stop the smoke from entering the room by squishing some weather seal foam between the window sections.

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I have done several things to solve this:

  1. Block every possible point that air can enter when the window is open. I use foam and weatherstrip.
  2. Seal the hose well at both ends.
  3. Get a decent hose. I replaced the hose that came with mine with a double-wall from Amazon; not only did it seal better at the ends but the smell dropped significantly from just replacing the hose.
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When you force air out of the room, it has to come in from somewhere. If that somewhere is right next to where where you’re venting… yeah, you’re going to suck all the smoke back in. Seal it up. And then replace the hose that came with the GF.


What Christy said. It might also help to ensure you have a source of room air that is at a distance from your exhaust. You could try it with a door open to see if it makes a difference.


Thanks everyone!

I will quickly tape the small gaps in the window and check the hose for pinholes today. If that works well, I’ll go for a more elegant and permanent solution, likely even get a better hose…I wasn’t too impressed with the one that shipped with the GF…

You can hold a flimsy tissue, or something that smokes like an incense stick, close to the gap at front/left side of the door when doing a cut. It should move towards the machine if at all.
If it is moving away from the machine, you may need to examine the exhaust run for too many turns, too far, and other issues which retard how useful the fan is.
My rig is very short, and yet I have found it useful to add additional exhausting. The foil tape used solved the last minor smell issue.

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I’m so sorry to hear that you’re been running into trouble with your Glowforge ventilating properly.

When your Glowforge is properly set up, you may have some harmless odor during printing which will rapidly dissipate. You may also smell something when you open the Glowforge lid after a print is complete. This is not harmful.

However, if you detect a strong, sharp smell that also causes eyes, nose, or throat irritation, or if there is visible smoke escaping while the lid is closed, shut off your Glowforge unit immediately. Smoke and fumes could be entering the room in excessive concentrations.

We’ve created a troubleshooting guide with illustrations. You can see it here:

I appreciate you taking the time to review the small gaps in the window your Glowforge’s exhaust host connects to. I’ve extracted the log files from your Glowforge to review your most recent prints, and it does appear that your units exhaust fan is working properly. Once you’ve reviewed the host connections, and the area where it ventilates outside, please let us know if you run into the same snag, and we’ll send over the next best steps.

Thank you everyone for your help. I started out this morning my simply taping the window so no air could infiltrate back into the house. I was satisfied with the results, though it wasn’t perfect.

I have a horizontal sliding window and have taken out the portion that slides. I constructed a new “window pane” out of 2in pink rigid foam that I had in the basement, stuck some weatherstripping on it, and put my new vent hose through it. It seems to work very well, but we are always windy at my house, so I think I was still getting some of the smoke and smell back in through the vent hose when the GF fan is off, even though the vent hose has a damper in it. I have ordered an inline fan that pushes 200cfm, so I will have that running before and after forging to help purge the air better.

Making the box that smoked up my entire house, was just a simple 50x50x50cm box. I made that same box, plus duplicated three of the sides, so forged a total of 9 panels today after making those modifications, and didn’t smoke the place up at all. I could smell the smoke while forging, but only standing right next to the GF. I think this will work well, especially once I get the inline fan in a couple days.

Thank you to everyone for your input…it was very much appreciated


Thank you so much for updating us! This is so great to hear. I appreciate you putting in the extra effort, and I’m glad the results allow you to print all of the wonderful things you’ve been working on.

I’ll close this thread for now, but please don’t hesitate to reach out to us directly at in the future if you run into any more trouble. We’re here to help!