Your Glowforge comes with the ventilation you need. I discovered that I was coughing and getting sore throats from my machine running. My 10 month old can't sleep through it. So I finally opted in for the inline fan. Please note, when you purchase the inline fan and use it on your Glowforge that you have read all warranty info and you may use it at your own risk. Here, I've explained which parts to get and why.
For your inline fan, you'll need a 6 to 4 duct reducer. Glowforge ducting is only 4" so that will open the gap for you to use a 6" inline fan. The elbow is to turn right after you've placed the reducer, otherwise you'll have an inline fan sticking out behind the Glowforge. My machine is against a wall, so that would be silly. Then comes the inline fan & hose. Then the 6" connector is for venting out of my laser cut wood for the window. Use the aluminum tape for a proper seal on all your parts. The inline fan is to help push more smoke out and quiet the Glowforge. Remember to turn ON the "Glowforge filter attached" in the app.glowforge.com settings. This will turn off the Glowforge fans so you can run your new one.
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