Since retiring and starting a new layout, I've been accumulating all the things I used to read about but couldn't afford: a NWSL Chopper, a second drill, a multimeter, and so on. I had an airbrush but was limited somewhat by the lack of a spray booth, so I sprang for a mid-price ($300) one. I'm not at the stage of painting and weathering on a daily or even weekly basis, and so my use of the spray booth could be measured in minutes rather than hours, but I notice that when using a rattle can to do some priming of small parts, there's a visible vapor in the air and a strong paint smell (detectable after I remove my respirator).
Somehow I expect that the booth's two fans will more or less instantly pull vapors out through its filter media; it sounds loud enough to be doing that. Should I remove a layer of filter, or will that defeat the purpose? Is there some way to test efficiency? Or is this par for the course, and I should relax and go on modeling? Any helpful hints?
Thanks in advance.
Is the booth exhausting outside?
Removing the filter(s) will definitely defeat the purpose.Paint particles will stick to the fan blades and whatever is in line with the spray booth outlet.If tightly fitted,the mechanical flitering will stop a very high percentage of the paint articles but the smell will still go through.If you don't want the smell,you'll need something to flow the air/smell to the outside like a clothes dryer through a window.
Yeah you need to vent that outdoors if you're using solvent paints. If you stick with waterbased acylics (in an airbrush) you can get away with venting it indoors with just the filters, but as said if you're using rattle cans (which contain solvent paints) you will need to vent that booth outdoors. The filters will only filter out the solid particles of paint not the gasses/fumes unless ventilated. You can use a flexible dryer hose.
Jay
C-415 Build: https://imageshack.com/a/tShC/1
Other builds: https://imageshack.com/my/albums
An ordinary GE (not the fancy Nutone premium stuff) kitchen vent hood pulls about 180- 200 cfm (cubic feet/minute) from your stove top. This is most visible when you put a tea kettle on the range and observe the steam rising toward the exhaust fan. It is not a "rush" of a column of air, but a directional "drift" upwards.
A standard (Holmes) 20 inch 3-speed box fan (like the kind you get at Wal Mart) pulls about 870 cfm at lowest speed, when placed in reverse behind my home-made spray booth exhaust port, through a pleated standard A/C fiber filter. There is a "noticeable" breeze moving the paint from the booth interior through the filter at low. If I spray enamel, I set it on medium, which I believe, moves air at > 1000 cfm.
The Paasche metal spray booth (with motor) pulls about 1100 cfm by comparison.
The basic idea is to ensure that there is a constant velocity pull of paint micro-particles and general dust towards the filter medium, whatever type you have, so that they do not hang in the air inside the spray area and redeposit onto model surfaces- but not so much air flow that it would disrupt the directional spray from an air brush or spray paint can from the spray source to the model's surface.
Some housekeeping chores I find are that, with extensive use (for me that is one-day weekly hobby use), either with my homemade one or the hobbyist/ studio type of spray booth (I have a Paasche at work) it requires that I reverse the filter (top for bottom) to obtain more use out of each filter and I clean the box fan blades and the Paasche built-in blades every 6 months, to avoid bypass build up of the small bit of paint that manages to pass thru the filter medium. I also take a flat spackle blade and scrape paint build up from the interior walls of both booths, every 3 months or so, to avoid additional particulates that may get disloged and fall onto the model surface.
Also- at Home Depot, there are several different flexible ducts (for use with dryer vents)- do not get a plastic one- get a heavy duty metal one if you want to exhaust outdoors.
Cedarwoodron
Definitely vent the spray booth to the outdoors. My spray booth was originally in my shop in our detached garage. It was vented to the outside, and did a good job of getting rid of the solvent vapours. When I built the house in which we're currently living, I built my shop in the basement, with an attached room for painting, again venting the spray booth to the outdoors. However, since the house was newly-built, it was much tighter than the former garage and my wife often complained about the smell of paint (and that included the times when I was spraying PollyScale or other water-based paints). A couple of years ago, I moved the spray booth to a small room within our current detached garage. This building is about 125 years old, so I had to make the room as tight as possible to keep the insects and other critters out. Recalling the problem with painting in the newer house as compared to that in the original garage, I also installed a closeable screened opening to allow make-up air to enter the paint room when the spray booth's fan is running. The results were well worth the effort - with the vent fan running and the air intake open, there is a noticeable airflow through the small room, and the paint odour is absent from the room by the time I've cleaned the airbrush, about one minute after painting is completed. Despite that, I always wear a two-stage respirator when airbrushing (regardless of the type of paint being used). Like any piece of safety equipment, once you become comfortable using it, it becomes second nature to do so.
Wayne
erosebud:
I suspect that part of your problem is that the rattle can is putting a lot of paint into the air - much more than your airbrush would. Perhaps you could try putting your workpiece a bit closer to the fans, but you still need to keep the spray can an appropriate distance from the target to avoid putting down too much paint.
As has been said, removing part of the filter system will only deposit a lot more paint on the fan blades and blow the rest out the back into the air again. One of the prime reasons for using a spray booth is to control the overspray.
Get out your airbrush and see how the booth handles the overspray from it, and as Doctor Wayne said, vent the booth outside.
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
I plan on using an artograph large spray booth with two fans. I intend to use a respirator mask as well using acrylic paints. I'll need to use my booth under the layout benchwork and wondered if I'd still have any issues with overspray in the room as there are no windows and may have to have the entrance door shut to keep the noise down in the house.
I thought I'd try without venting outdoors but can if need be. I'll only be using acrylics. Is there much danger I'll get any overspray outside the booth?
Jim
Raised on the Erie Lackawanna Mainline- Supt. of the Black River Transfer & Terminal R.R.
Capt. GrimekI plan on using an artograph large spray booth with two fans. I intend to use a respirator mask as well using acrylic paints. I'll need to use my booth under the layout benchwork and wondered if I'd still have any issues with overspray in the room as there are no windows and may have to have the entrance door shut to keep the noise down in the house. I thought I'd try without venting outdoors but can if need be. I'll only be using acrylics. Is there much danger I'll get any overspray outside the booth? Jim
Assuming the fans are running at a good speed then it depends on the size of the booth and what psi you're spraying at. If the booth is at least say 14x20 and you're spraying ho and smaller stuffand you're spraying ar 30 psi and less, you shopuldn't have any overspray, but I would still leave about 6-12 inches clear around both sides of the booth.
Thanks so much for very solid information, friends. I should have mentioned that I have in fact almost vented my booth to the outside: the exhaust end of the vent is fixed about four inches in front of a basement window that I open for spraying. So I get a little help there. And I always wear a two-stage respirator now (another thing I bought in retirement) instead of just a dust mask.
Your hard data, experience, and other observations are most helpful. I'll be doing a better job thanks to all of you.
erosebud the exhaust end of the vent is fixed about four inches in front of a basement window that I open for spraying.
Do you have one of those two-pane small windows that tilt in? That's what I have. I found that they sell a flat aluminum plate that you can cut down to replace one of the panes. It has a hole in it pre-sized to accept one of those flapper valve equipped aluminum dryer duct vent pieces.
Thanks Jay. That's what I figured but wanted to check. Hope that helps the OP too.