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Hi All

I'm working in a basement shop and trying to figure out my spray setup.
I'll be shooting waterbased only. I own an 18" through the wall style exhaust
fan with louvers on the outside. I believe it's in the 2500-3000 CFM range.
I want to set up my spray area in a small 6'x7' room within the basement.
My house is built into a hill so the back of the basement is below grade.
Although this room has an exterior wall it is below grade and I do not want to
get into cutting through the foundation and installing a window well.

This leaves trying to figure a way to use it on an interior wall and ducting it approx.
8 feet to a wall above grade.
The plan would be to build the fan into a wall behind a filter arrangement.
The easiest way to run the duct would be to somehow adapt to something circular & flexible.
This where I'm stuck. The fan moves some serious air so I'm not sure of the result of
choking an 18" fan down to say a 6" dia.

Any ideas?

Thanks
Bob Hames

Your fan is more than big enough. I believe it will still be adequate if choked down to 6". I believe you'll be finished spraying a guitar before you fog up the room.

Added: Remember, even with waterbased finish, and good venelation you still need breathing protection.

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Bob, I shoot waterbased. I set up a knock-down booth in my shop & exhaust into my dust collector. Seem to work fine. Don't know if I'd want to go through a wall unless there's fumes.

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Dave
Milton, ON

Thanks for the replies gents

Woody I have no doubt as to the fan being large enough.
I used to use it to exhaust the shop through a window and if I
didn't open another window it would slam most of the doors in the house.
I'm just not sure of the physics involved in reducing the output.

Hey Dave...appears we're almost neighbours!
Can you expand on your set up a bit?
Do you leave you're output hose going into the bag or do you duct this outside?
I 'm guessing you have some kind of filter setup in your knock down booth?
Any chance of pics?

Cheers
Bob Hames

Dave, (and Bob) the problem with venting finish fumes........(I guess it's not really "fumes" but you know what I mean) with a dust collector is the fogged finish will stick to the fine dust inside the dust collector and stop up the bags. If you notice a reduction in efficiency with your dust collector check and see if the bags have a film of dried finish and dust stuck inside them.

_________________
I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

Bob, here's a pic of my booth. It's basically a couple of bi-fold doors (always available on "big pick-up" garbage day). Ply inserts, pinned to runners attached to the doorswith big finishing nails, solidify the whole thing. The dust collector is in a closet behind the booth. The inlet (visible just through the hole) press-fits through the hole and I ductape filter media overtop.
Woody, I don't really have the problem you describe with waterbased. Nothing makes it through the impeller, chute & into the bags other than powder. Any "still-sticky" mist is caught in the filter media & quickly "powders" into the collector if you brush it. I normally wash the bags before & then after spraying. Hope this helps.

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Dave
Milton, ON

I had forgotten how quickly waterbased finishes dry. I'm sure they're fine for a dust collector. I tried spraying varnish, using my dust collector for exhaust and it turned the bags to concrete. I'm back to spraying in an automotive paint booth for now.

_________________
I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

Hi Dave

Thanks very much for the pic and the explanation.
I might give this a test try.
The only thing I'm not sure about is that as my collector uses
this canister style filter. I guess I could look at buying a suitable bag style
filter for spray use only?

Thanks Again
Bob

Seems like if you just used rectangular heating duct that you could go up between the wall studs just like the heating supply to the rooms if you have central heat and just put the vent through outside wall instead of into the room. You might also give some thought to getting an old ac or furnace blower and using it. I plan on using one for my booth. I have a 3 speed so it can be left on low when drying. I use nitro so fumes are a problem. But you might be able to mount the blower on top of the booth and vent it out side like mentioned above. Just a thought.

Dave, do you find much overspray getting out into the rest of your shop? Your small booth got me thinking about setting up something similar that is permanently hung to a wall in my garage/workshop--Swing a couple of doors open to act as sides and prop up a top and lower shelf. Then either duct through a narrow chute out and behind the back or directly out the bottom. When not in use, it would sit fairly flat against a wall and is not underfoot. Hmmmm... I used water based as well.

Ken

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Yes, this interests me as well since I have been spraying outside and my shop is quite small.

_________________
Steve Smith
"Music is what feelings sound like"

There is a bit of "fogging" & a bit of dust settled on things afterward but with waterbased, I don't think you'll have a problem... it's "sticky" life is very short. No more dust than after sanding a tabletop.

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Dave
Milton, ON

Dave,
Looks like you have a hook to hang the work on in the booth. Do you do all the spraying with it on the hook or do you do some of spraying while holding the work by hand?

_________________
Steve Smith
"Music is what feelings sound like"

.....I've almost NEVER used the hook! (although you could...the eye is just loosely screwed, so it spins.)
Everything I do is done hand-held. I use a bolt-on neck, so I made handles using that hardware for both necks & bodies.

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Dave
Milton, ON

Kind of what I figured. I use handles as well for the neck and body.

_________________
Steve Smith
"Music is what feelings sound like"

Thanks to Dave for sharing his booth.

As I do each evening, I just went through the new posts, opened all the ones that interested me in their own tabs and then set about reading them.

The VERY next thread I read after this one was the one on the downdraft table.
It got me thinking....

Why not kill two birds with one stone and build a knock down spray booth that sits right on top of a downdraft table?

What do y'all think of this concept? Would the downdraft filters grab enough of the nasties in the over spray to not kill me in my ventilator mask?

Dave

If spraying WB finishes, than keeping the air inside your shop (like a downdraft table or from the dust collector) would work fine, but you really want to expel the fumes from your shop (and house for that matter) if spraying any type of toxic finish (nitro, poly).

Dave, I think a down draft table would work just as long as you have enough filter before the fan. Furnace filters are pretty inexpensive and you can always double or triple them up to catch the dried particulate from spraying. That said, you'll need a strong enough fan to suck the overspray down.

Check out my signature line "a post of my shop" and you'll see my set up. It's what I call a semi-knock down spray booth and it works great! This way I can leave guitars in there and let any off gassing take place while I still work in the rest of the shop. I've switched (for now) to WB lacquer so the explosion proof fan isn't necessary but I like the fact that I have it for future use.

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Here's my portable knock-down spray booth. I have a top that I can place across the wings but I found it not really necessary and besides it will let more light in without it. I normally use the booth at my open garage door but will be venting to the outside through the wall at a later date so I wont be at the mercy of the weather.



http://s762.photobucket.com/albums/xx26 ... 0_5712.jpg

Thanks for all the feedback everyone.

Here is what I'll be trying out tomorrow.
It's sized for 2 standard 20"x25" furnace filters to be fixed to the front
& is attached to my small dust collector(approx. 1100 cfm)



If this fails to be effective enough I will morph it into this
and install my large 18" fan and duct it with 10-12" flexible hose.


Report to follow.

Cheers
Bob Hames

Does waterborne dry fast enough that hanging it in a shop and collecting any dust moving around isn't a problem?
I always thought that one real advantage to a spray room or booth was that the air is filtered for dust into the room so that one doesn't get dust particals shot onto the work while spraying and while hanging.
The hood looks good. I made a booth one time out of 2" X 4' X 8' sheets of the blue styrofoam sheathing. Light weight for sure.

Chris,

I don't worry so much about the dust getting on the finish as it does dry fairly quickly, and I always rub out the finish anyway. But my workshop is in a corner of my 4 car garage. After spraying, I have a fine powder over the entire garage, even with my overhead air filtration system running full out. The dried overspray vacuums up easily enough, but I have to clean everything when I am done. My goal is to minimize the mess I make to the rest of the garage when spraying. I'd love to be able to spray without moving all the cars out but not sure I'll ever get to that point without a sealed off area with a powerful external exhaust.

Ken

_________________
http://www.casperguitar.com

Oh I hear you all as I don't have a spray room yet and it really bugs me.

Hi All

Another post made me realize that I neglected to report the results
of my spray exhaust setup.
I used the setup connected to the dust collector and results were
for the most part good. There was no noticable "fogging" in the room,
but I must say there was still a light white powder coating on things.
Perhaps my choice of filter was not good (I used the pleated furnace type)
There was a small amount of overspray from not keeping the gun in the filter
area as well, I think.

I think I will try my more powerful fan on the next guitar, and exhaust outside.

Cheers
Bob