Window mounted fan for spraying lacquer

[difalkner]

This window mounted fan support is a long overdue shop upgrade project.  Every time I spray lacquer I had to rig the fan to stay in the window (it fell once and bent the blades).  And it didn't work very well, either.  As much air came in the window as the fan blew out.  Also, every bug that got near the window got sucked in by the vortex on the periphery of the fan.  This is much, much better!

Enjoy!

David

[Coop]

Pretty cool deal David. I just knew you were going to cut the hex in the walnut with the CNC!  And I did watch it 3-4 times! 

[difalkner]

I probably shouldn't admit this but I have cut the hex on the CNC before... OCD!!   I made some hold down knobs and cut the hex in those but this method works better.

David

[mat60]

Nice David. I bet that works allot better that just sticking a fan in the window opening. 

[difalkner]

Thanks!  Yes sir, when the fan was just sitting in the window it took at least 10 minutes to clear the fog, even with the low overspray of the HVLP gun.  Now it's basically pulled out real time while I'm spraying.  The longest I recall seeing any sort of a cloud is about 30 seconds and that was only if the light was right to even see it.

David

[mat60]

I no allot about lacquer fog.  To much of that stuff is not so good.  I lost my 30 inch wall fan in my shop two weeks ago and need it invest in a new one soon.  It sounds like the size of your fan is working well for you.

[difalkner]

This 'little' 20" fan puts out 4650 CFM which is about double what most 20" box fans do, so that's got to help.  Got it from Amazon - Firtana 20" fan.  I don't know how it compares to the 30" you had, though.

David

[drzaius]

Nicely done, but I guess I'll be that guy who brings up the dangers of spraying & electric fans. A better alternative to sucking air out with a fan would be to pressurize the shop with a fan blowing in & opening another door or window to let the fog out. Of course, if it's a waterborne finish there isn't the fire/explosion hazard, but the fan will stay a lot cleaner if it's blowing in rather than sucking out.

[mat60]

I agree and the best fan to use would be a spray booth fan.  They are safe but can cost around 2 grand or more for the size I need. ..   David,  This may sound funny but 10 years ago I got a great deal on a new 30 inch  (Attic) Whole house fan with shutter. It was 5800 cfm low speed and 7600 on high. It was belt drive so it was quiet as far as fans go.  Installed it in the wall and it worked great.  Always had to make sure to blow the dust out of the motor after sanding or spraying.  I look forward to having a new one.

[difalkner]

1 hour ago, drzaius said:

Nicely done, but I guess I'll be that guy who brings up the dangers of spraying & electric fans. A better alternative to sucking air out with a fan would be to pressurize the shop with a fan blowing in & opening another door or window to let the fog out. Of course, if it's a waterborne finish there isn't the fire/explosion hazard, but the fan will stay a lot cleaner if it's blowing in rather than sucking out.

That's not near as efficient at removing the fumes quickly.  I understand the principle and reasoning but that would cause the vapors to remain even longer and I think that would be worse.  Getting rid of the odor quickly so it doesn't waft into the house where Sandy will have to endure it is paramount for me. 

And this is not a brush type motor so no sparks.  Also, the switch mounted to the motor, where a spark is probably possible, is always on high and I start the fan with a remote operating a solid state relay so no sparks there, either.  In addition, the fan is always running before I spray and the tiny bit of a cloud is gone so quickly that I doubt even an open fire would cause a problem.

I would love to have a real spray booth with water bath, explosion proof motor, proper lighting, etc. but that's just simply out of the question.  This fan works fine and has for almost two years and it's paid for - all plusses in my book.

David