Temporary vent connection

The basement room where I have my glowforge has no windows to put the vent through. I did not want to put a hole through the wall, so I decided that the door was the best place to pass through. I therefore needed a system that would allow for temporary hookup, and easy disconnection of the vent, while remaining airtight. A ½ hr and $30 at Home Depot resulted in a mashup of plumbing supplies.

You may not want to cut up a door and do it the same way, but if you are in need of something similar, I hope that the description that follows is helpful. Of course, I didn’t take pictures until I was half way done, so you’ll have to use your imagination for some of it.

I cut a hole in my door just larger than the small pipe diameter on the closet flange. It turns out that there is a ridge on the underside of the flange that required a larger diameter, so there was a loose fit in the hole. The red rubber seal does come off to make the fit easier. Eight screws, and the closet flange was securely mounted to the door, with the flange itself outside.

The black “duct to duct increaser” is a press fit into the closet flange. I trimmed the length of the large diameter to about ½ of its original length with some tin snips.

The louvers are a bit of a tight fit, but will slide over the protruding large diameter of the increaser, and fit up reasonably close. It does not look wonderful, but at least it is a way to provide some protection to the vent. The glowforge has plenty of air pressure to pop the louvers up when in use.

On the inside, you can see the gap between the flange and the hole in the door. But after you put the rubber back on, the cap hides the gap pretty well.

The “3-4” sewer drain adapter” fits tightly into the end of the supplied duct, and fits up perfectly to the closet flange.

So, you just pull the cap off and press the vent on, and reverse the process when you are not using the glowforge.

Here is the list of parts that I used:

4 in. PVC DWV Gasket Closet FlangeSioux Chief 4 in. PVC DWV Gasket Closet Flange Model #886-GP $17.28

3 in. to 4 in. Plastic Duct to Duct IncreaserEverbilt 3 in. to 4 in. Plastic Duct to Duct Increaser Model #INC34EHD $2.38
4 in. Louvered Vent Cap in WhiteEverbilt 4 in. Louvered Vent Cap in White Model #LC4WXHD $4.88
3 in. x 4 in. PVC DWV to Sewer and Drain AdapterNDS 3 in. x 4 in. PVC DWV to Sewer and Drain Adapter Model #3P12 $3.90
4 in. PVC Sewer and Drain CapNDS 4 in. PVC Sewer and Drain Cap Model #4P06 $2.10


I wasn’t happy seeing the gap between the pipe and the door every time I hooked up the vent. My son and I measured the pipe sticking through the door drew up a flange in InkScape to fit it. I wanted to try out the two sided engrave alignment (that you can read about elsewhere on the forum), so I made a design for one side, and my son wrote a note and wrapped the text for the other side. The technique imports an SVG with the both sides of the engrave visible, but you tell the glowforge to ignore one of them.
We engraved the text and made cuts for the inside and outside of the flange When the first run was finished, we used tape to take the parts out while holding the stock so that it would not move.

We put the flange back into the hole upside down and ran the other engrave while ignoring all of the elements that went on the first side.

We weeded the engraves using duct tape
And since we measured twice (and laser cut once!) the flange fit right up to the pipe and covered the gap.


Love your son’s sense of humor :slight_smile:

When I built my brick pizza oven, every one of the kids put their hand prints or wrote something in the final layer of insulating concrete which was covered up by perlite insulation and a faux-Italian house. Until it gets torn down, no one will see those musings. Your son’s inscription reminded me of that and I just did the “dad going down memory lane” thing :slight_smile: Thanks!


Clever solution! Thanks for the write-up too.

Great idea! I am facing a similar problem, as I have decided to not put my GF into the upstairs room as I had originally intended.

Neat solution, and bonus for incorporating a laser-made part.

Is it possible for someone to come up, take the louvers off, stick their hand in and knock the cap out, and reach up and unlock your door?

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hmm. good thought. I know my hand won’t fit, but a small one might. We have a bar across the door up higher as well.

Very nicely done.