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cybor462
11-03-2007, 01:38 AM
I finally got tired of all the over spray and smell. I did have an out building to paint in but it got destroyed last winter. I have been doing it (wonder what he is talking about:o ) in the shop and well it is just not the place to DO IT:)
I decided to build a wood booth. Went to Home Depot got some 2x4's, flake board for the walls. Got some cheapo furnace filters. Now I need a fan as I already have a 1/3 hp motor that turns 1750 rpm. I will use a pulley setup as a drive but wonder what type of fan to use. I remember days of old when houses had ventilators and they were fans driven by pulley and motors. I hope to use that type.

Any suggestions where I might find them? I was hoping for a 16 - 20 inch fan. I can come up with a pulley and make a shaft if needed. Just hope to find a fan riding on bearings.

Any thoughts?

Fasttrack
11-03-2007, 01:48 AM
you might consider checking out the agricultural sector - the fans used in hog buildings, chicken coupes, stables, etc are just big fan blades that are run from a motor. Check out farm and home, farm and fleet, etc and there are some online suppliers too.

cybor462
11-03-2007, 01:52 AM
I thought about that but they were always very large. I never saw a 16 - 20 inch fan. Normally those things are 24+ inches and use 1-2 hp motors or larger.
If you know of smaller ones I would be willing to listen.
Being out here in cow country and pig and chicken country I see those fans all over. I would need a booth the size of my house to use one, Not a bad idea really but I do not have the room.

dp
11-03-2007, 02:19 AM
Make sure what ever you get is designed not to throw sparks from static or electrics.

torker
11-03-2007, 02:19 AM
I've been on both sides. Did "backyard" paint jobs for years. Then i enrolled in a 7 month autobody course a few years ago. Wow! I couldn't believe the difference that a downdraft booth could make. Beautiful paint jobs...spraying with no mask...(not always...lol), no mess all over the shop. etc.
I was to do it...2X8's under the floor with filters mounted in between them.
I really don't think your fan is strong enough.
The "real" ones will suck off your underwear!

cybor462
11-03-2007, 02:28 AM
First lets make things perfectly clear I do not wear underwear!!:rolleyes:

I do really....but I was thinking on making my booth with the fan on the top side section drawing out thru filters. The booth will only be 4' wide and 3' deep and 6' high. With a 20" 3 blade fan turning at whatever rpm I would need by pulley size I think that would do the job. Remember this is a small booth for small parts..operated by a small brained guy:o

I thought of the spark factor and decided I was going to mount the motor topside where it would be isolated from the booth. Not sure but I do not think it would be a problem.

speedsport
11-03-2007, 03:03 AM
I built a spray booth not a whole lot bigger than your, I found a explosion proof fan on craigslist for $75, I felt it was a steal. You really should think about one too, regardless of which side of the wall you put it there will still be highly volitive mixture flowing over the motor, one spark and you are toast. And down draft is the ticket, other wise crap is going to fall on your wet paint.

Fasttrack
11-03-2007, 05:12 AM
actually i just snagged an aluminum fan that was 18" in diameter for a project. i have to make a shaft and bearings for it but it was from a hog building. i'll have to do some sniffing around and figure out what they were originally used for.

lazlo
11-03-2007, 09:33 AM
I use a standard 2' x 2' box fan in my paint booth, and just tape a HVAC filter on one side to keep the overspray from spreading.

Steve Steven
11-03-2007, 09:57 AM
Go to Grainger for fan, they have many of the type you are thinking about. You have to establish a account to buy from them, but it shouldn't be a problem for you, just use your business name. www.grainger.com

Heres one, says "limited supply" but they have others.
http://www.grainger.com/Grainger/items/3CC73


Steve

MGREEN
11-03-2007, 08:13 PM
First lets make things perfectly clear I do not wear underwear!!:rolleyes:

I do really....but I was thinking on making my booth with the fan on the top side section drawing out thru filters. The booth will only be 4' wide and 3' deep and 6' high. With a 20" 3 blade fan turning at whatever rpm I would need by pulley size I think that would do the job. Remember this is a small booth for small parts..operated by a small brained guy:o

I thought of the spark factor and decided I was going to mount the motor topside where it would be isolated from the booth. Not sure but I do not think it would be a problem.


cybor462,
How about a blower unit salvaged from an old forced hot air heating system, you know the type, looks like a big squirrel cage.
I've seen pics of them set up as dust collection units for a wood shop.

Oh, and the tension gauge that you sent to me is great!
Nice job Jim!
It arrived emblemished.
Sorry I didn't get back to you right away, I got caught up with
this and that, you know how it goes.
Thanks again.
Mike Green

tfleegal
11-03-2007, 08:48 PM
Jim,

like Mgreen just posted. A furnace fan can also be adjusted for air flow by pulleys or a electric controller ANd the motor can be isolated from the air flow.

Just my 2$

Terry

TECHSHOP
11-03-2007, 11:47 PM
Something that I have swimming in the back of my head, was to use one of the aftermarket cooling fans for an auto. When I saw a electric type on sale I started to think about down draft tables and a wood shop "cyclone" dust collectors. Maybe there is one in the size you are looking for?

cybor462
11-03-2007, 11:51 PM
Go to Grainger for fan, they have many of the type you are thinking about. You have to establish a account to buy from them, but it shouldn't be a problem for you, just use your business name. www.grainger.com

Heres one, says "limited supply" but they have others.
http://www.grainger.com/Grainger/items/3CC73


Steve

Heah Steve thanks for that tip. I do have an account with them. I do not use it as it seems their store near me never has what I need and the guys do not take the time to see if they can get it. Make me feel like they could care if I get what I need or not. I will check it out. Thanks

J Tiers
11-04-2007, 12:09 AM
1) If you spray any flammables, you DO want a fan that is safe for flammable vapors. Especially with a wood ( :eek: ) booth.

2) With paint booth fans, the whole story is "face velocity". No, it's not measured as you run away, it is the air velocity through the front opening (face) of the booth.

In a good industrial booth it is enough to flap your pants.... The idea is that all the overspray goes out the filter and none leaks out the front in some sort of eddy or reverse flow.

You can figure the airflow by knowing the air volume the fan can move through the filter and ducts, and dividing it by the face area of the booth opening. In a "real" booth you get over 10 feet per second, IIRC.

Looking at the FAQ on the Binks site http://www.binks.com/Technical%20Support/Spray%20Booths.pdf

I see that 100 ft/minute face velocity is suggested as the minimum.

cybor462
11-04-2007, 12:12 AM
I thought about an old furnace air blower fan. Did not fit the design I was looking at. I want to make a filter slot using some angle iron and then bolt the fan frame to the angle. I am using square furnace filters so a square fan was looking good. I will mount the motor to the top of the booth and have the belt connect to the fan off the side. This keeps the motor out of the air path and also allows me to mount it where there is room on top of the booth.

I did actually build the booth today 4' wide x 3' deep by 77" tall. I installed castors on the base which are 3" so it is a total of 80" tall that will fit thru my door. Had to build it outside.

I need to cut a hole in the side for the filter/fan mount, bolt on the angle iron and mount the fan to that. I have a box to wire a switch directly to the booth.

The booth is closed in 3 sides full and about a little less than 1/3 in front. I will install a bar inside to hang the parts to be painted. I plan on installing a plastic shower curtain on the front to close off as much as I can when I am painting. I feel this should work fine.

While we are at it any ideas on what rpm I should run it at. The motor is a 1/3 hp 1750 rpm. The fan as Steve has put a link is around 24" which is perfect as my filters and mount will be 25".

Any help for rpm is appreciated so I can figure pulley size.

Seems I can't type as fast as others posting:D

cybor462
11-04-2007, 12:14 AM
1) If you spray any flammables, you DO want a fan that is safe for flammable vapors. Especially with a wood ( :eek: ) booth.

2) With paint booth fans, the whole story is "face velocity". No, it's not measured as you run away, it is the air velocity through the front opening (face) of the booth.

In a good industrial booth it is enough to flap your pants.... The idea is that all the overspray goes out the filter and none leaks out the front in some sort of eddy or reverse flow.

You can figure the airflow by knowing the air volume the fan can move through the filter and ducts, and dividing it by the face area of the booth opening. In a "real" booth you get over 10 feet per second, IIRC.

Looking at the FAQ on the Binks site http://www.binks.com/Technical%20Support/Spray%20Booths.pdf

I see that 100 ft/minute face velocity is suggested as the minimum.

Answers my question for fan flow.

Thanks

I will check the fan and see what rpm will be needed for that flow or higher if possible.

Right now I will be spraying aerosol enamel (spray bombs) should not be a problem. I do want to powdercoat as well but that I would feel better with a proper fan. Right now the paint is needed badly, the powder coating can wait.

brucepts
11-04-2007, 09:11 AM
Hey Klem you need a blower like this one it'll suck those fumes out :)

http://www.flowbenchtech.com/blower.jpg

http://www.flowbenchtech.com/blower-1.jpg

wlpier
11-04-2007, 12:26 PM
Hey Jim, give http://surpluscenter.com/ a try. Look under electrical.

Samuel
11-04-2007, 01:15 PM
I may be pointing out something that you have already ruled out as an option, what about a positive pressure spray booth? where the fan/ blower is supplying clean air to the booth and the exhaust is going over a splash plate and out , no fouling of the fan blades, and loss of efficency, also no dust etc creaping in through the cracks.


Samuel

cybor462
11-04-2007, 04:09 PM
I do not paint for a business just need something to prevent over spray. I paint tools. I have been spraying them in the bay side of the shop and I have no issue with dirt or dust. The stuff dries too fast. My purpose for the booth is not to try to solve any paint issues just to contain overspray.
By using the booth it will filter and catch the OS and stop the paint dusting of the entire shop.

Painting is not my thing. Just have to do it, when I finish tools I need to paint them.

cybor462
11-05-2007, 12:14 PM
Go to Grainger for fan, they have many of the type you are thinking about. You have to establish a account to buy from them, but it shouldn't be a problem for you, just use your business name. www.grainger.com

Heres one, says "limited supply" but they have others.
http://www.grainger.com/Grainger/items/3CC73


Steve
Yepper they are so limited they say they are discontinued and do not have them. I asked for the replacement
and was told it cost 400.00 where the one in the link was 100.00 SO I guess I keep looking.:mad:

lazlo
11-05-2007, 12:26 PM
I do not paint for a business just need something to prevent over spray. I paint tools.

Cybor, like I posted earlier, I used a standard box fan with a furnace filter when I sprayed my Clausing. In this picture I pulled the plastic sheeting away from the fan so you could see it. It worked great:

http://i164.photobucket.com/albums/u15/rtgeorge_album/PaintBooth.jpg

cybor462
11-05-2007, 12:38 PM
I did that at one point when I would paint my new engines and it killed the fan real quick. I will be using this booth a couple times a month so I need a little better setup. I called Grainger a few minutes ago and asked why they still showed that fan on the web if they no longer had it. i was then told they had a few. My local store I guess did not want to bother to get it for me.
I do have it ordered and it will be here tomorrow.
I think that will be the ticket.

Thanks for the suggestion.
Nice looking paint on that lathe. I really like that chip tray, nice and deep.

lazlo
11-05-2007, 12:47 PM
Nice looking paint on that lathe. I really like that chip tray, nice and deep.

Thanks Cybor -- that was when I was dry-sanding the Polane, so it was covered in a layer of chalk. It looks much better when I was done ;)

I'm finishing-up some of the hardware, I'll post some pictures when I'm done...

cybor462
11-07-2007, 12:10 AM
Will have the fan tomorrow and with luck will have a booth this weekend. Decided to buy a HF 1/2 hp motor for 60 bucks. Should do the job.

Lazlo..I sent you a PM

cybor462
11-08-2007, 02:37 PM
Picked up the fan today. Wow it is much more massive than I expected.
http://www.grainger.com/Grainger/items/3CC73
It may be too big for the job but I have to use it now. Will take some head scratching but I will get it done.
Found a pulley and may make the second. Will check to see what they sell for. If they are not much I will buy one.
I will post pics when it is done

Steve Steven
11-08-2007, 03:25 PM
Cybor,
I have one of these in my attic as an exhaust fan, been there for nearly 30 years, still on its origional bearings and motor (a used washinging machine 1/3hp open motor), so it should be fairly hardy. I would make a set of pulleys up that will give the fan the required 710rpm listed in the catalog, and put it in a short tunnel drawing from your paint booth, with the filters at the booth wall.

Steve

cybor462
11-08-2007, 03:37 PM
Just found them on Graingers site. A 2" pulley for the motor and a 5" for the fan will give me 700 rpm's at the motor rpm of 1750.
Total cost for both pulleys is 20 bucks for cast metal. Should be ok and easier and cheaper then making them.

cybor462
11-08-2007, 03:51 PM
Next question, do you guys think having roughly 56" between centers of the pulleys is too much without an idler? My thought is as long as it is tight and not flopping around causing vibration would be ok without an idler.
Any thoughts?