Monday, December 30, 2013

092 The Navajo Mining Railway - Airbrush Cabinet Vent


I needed to hook up my air brush cabinet.  It is Christmas Time, which means we've spent a lot of cash on presents, so I don't have $150 lying around to put in a vent.  Let's try to do it on the cheap!  Actually the real problems are:

1.  My basement area is just too small until we buy a new house...working on it.
2.  I don't have a place in my shop for the air brush cabinet
3.  I don't want to spend $150 more on the airbrush cabinet
4.  I don't have enough uninterrupted time today to do this right.

After searching the stores for a higher velocity bathroom fan, I did find this.  It is an Inductor air mover.  I don't paint with solvent paints, so this in line air mover might just work.  It is rated for 160 cfm to 250 cfm.  This is a lot more than the noisy bathroom fans!

Here is a look inside the 6" pipe.  The fan wires up to 120 volt and is very secure, and after a is very quiet!

Here is the window where I plan to use to vent the fumes. This is a basement window that gets good natural draw out...perfect.  It is under the layout, so it will not be seen.

Here is the airbrush cabinet that I made over three years ago.  It has never been used.  The light had been missing for some time, and I just recently found it.

The rear of the airbrush cabinet is a 6" vent...perfect.

Using painter's caulk, I heavily caulked and sealed the vent.

The window will take a 23" by 14" plate for the vent.  Using a small piece of 3/8" plywood, I cut the board.

After test fitting in the window, I trimmed a little more off.  The next steps were not photographed because I was up in the garage, and it was very I wanted to finish as quickly as possible.  Essentially what I did was cut a hole in the plywood, and mount the fan.  Then I build a box around the fan assembly to protect it and to hold the wiring.

Here I am wiring a SPST switch and adding a power cord.  The box is made of 3/8" plywood using glue and 1" brads.

I put two handles on either side of the box to make it easier to move in and out of the window.  The initial tests of the fan draw were disappointing.  This is no where near 160 cfm...probably more like 70 cfm.

I connected the duct work to the cabinet and the vent and hit the switch.  Oh, this is not good.

I gave it the match test.  Essentially you light a match in the cabinet and there should be enough draw to pull the flame to the back of the cabinet, but not quite blow out the light.  Or, you can blow it out and watch the smoke drift to the back.  Neither happened.


Now I'm out about $30 and STILL have to build a proper vent.  That sucks.


1.  Sometimes cutting corners doesn't work.  Stick with tried and true methods when money is involved.
2.  Test the vent fan thoroughly before installing it.
3.  If you don't have time to work on something properly...just wait until you do have time.


  1. I really appreciate that you posted this. It is helpful to see what you are thinking and that you too are trying things that sometimes don't work out. It is also nice to see someone working on a more reasonable budget. I sometimes get the feeling that everyone else working on a layout is rich. Thanks for taking the time to write the blog. Keep at it!

  2. LOL...they never post mistakes in Model no one ever makes any! For is just how I learn. Some disastrous, some not so much. Either way, learn from my goof ups!

  3. Scott you need closer to 300 cfm looking at the area of your booth. The goal is to get an air movement of about 100 fpm across the opening. Take a look here

  4. Man, I've had an idea to do something similar to this for a bit too. That's too bad it didn't work out. Is it as simple as finding and adapting a better fan? I've watched a number of videos on YouTube that build stuff like this and their seem to work out. You're probably pretty close.

  5. Here is what I think I'm going to do. I'm going to bite the bullet and buy a more expensive squirrel cage fan, and reduce the duct size to 4" where I can get better components and a plastic, more flexible hose. Stand by for more details on this project.

  6. Bruce, I worked on a paint booth with about 300 cfm once...and it dried the acrylics faster than they could be applied. I had seen this site before, but their calculations are based on real automotive paint booths..and don't work for scale stuff. All I need it to do is to move loose paint particles to the filter, and to draw out solvent fumes and keep them out of the room. 160 cfm should do that...I just didn't get a fan that actually pulled that much. Drat.


Thanks for your comment!