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gerald_martin
01-20-2009, 08:55 AM
Hello All:

I have a small (8'x24') spray finish room in my new shop building. There is a filtered air inlet from the main (workshop) part of the building.

I'm looking for a small exhaust fan to vent fumes to the outside. Would prefer if it could fit between two studs on 24" centers, and have a louvered vent.

Any ideas or suggestions? Definitely want something safe as I spray lacquer occasionally. This is for occasional use, not continuous commercial.

Gerald Martin

Call-Tech
01-20-2009, 11:59 AM
Grainger sells them, however they might be cheaper if you can find it elsewhere. They have smaller ones in 12", 18" etc.

Here is a link to 24" Grainger exhaust fan with shutter. Has fully enclosed motor which protects against explosions if you spray flammable products.

http://www.grainger.com/Grainger/items/1HLB2

rb99
01-20-2009, 12:09 PM
If the fumes are flammable, then you have to watch out for fans that blow the exhaust over the running motor. Automotive spray booth fans have the motor encased on the outside of the fan housing and spin the fan with a belt that is also enclosed.

It should also have non ferrous blades so if they get bent and scrape the side they don't cause sparks...


P99

wberminio
01-20-2009, 12:20 PM
If you spray flammable be sure to get an Explosion Proof Motor!!!
DO not take chances.
Any spark can create an explosion from the spray fumes,even if only used occasionally.
It only takes on time.

Erminio

dakers
01-20-2009, 12:21 PM
you can copy and paste this into your browser.
in ebay looked for paint exhaust fan.
you can put a motor on this if you can get it at reasonable price. check craigslist also.
i always look for bargains because i do not have enough money for everything. but i do have a $4,000 bicycle so maybe i do not want to spend alot on exhaust. We bought a spray booth at auction fro $4,500. then had to put in fire suppression. had to run the tube out 6 ft from building for fire code. I could have got another good bicycle with all that money.


http://cgi.ebay.com/Dayton-Tubeaxial-18-inch-fan-exhaust-spray-booth_W0QQitemZ140294893759QQcmdZViewItemQQptZComm ercial_Painting?hash=item140294893759&_trksid=p328 6.c0.m14&_trkparms=72%3A1205|66%3A2|65%3A12|39%3A1 |240%3A1318|301%3A1|293%3A1|294%3A50#ebayphotohost ing

cabnet636
01-20-2009, 01:13 PM
after looking at the cfm range and price of the grainger, tools usa is a bit more expensive and this is a good bit more than i paid for some of these just 18 months ago,

http://www.toolsusa.com/asp/item_detail.asp?T1=PBE+9MS+LSD1633XVA20&GENB=&UID= (http://www.toolsusa.com/asp/item_detail.asp?T1=PBE+9MS+LSD1633XVA20&GENB=&UID= )

gerald_martin
01-20-2009, 03:14 PM
Thanks for the input, everyone...

Grainger's fan looks alright but it is not rated as explosion proof, even though the motor is sealed...

http://www.industrialfansdirect.com/LFI-AX18-4.html

will I need to spend $700 to get something functional and safe?

Anyone?

Gerald

bcammack
01-20-2009, 04:18 PM
Or you could put the room under positive pressure so the air is forced out through the filters.

If the fan is across the room and not near where you are spraying, whether or not it is explosion-proof isn't very relevant. If a motor is brushless and has no contactors, there isn't going to be much of an opportunity for a spark to occur.

Call-Tech
01-20-2009, 05:38 PM
It is my understanding that a totally sealed motor is sufficient for use in spray booth. If the contents of spray booth is that explosive then gasketed and sealed fluorescent lights become a larger concern than the motor in the exhaust fan.

-Fred

glcochran
01-20-2009, 05:43 PM
look at ebay, and search "Multifan" there is a 20inch currently for sale. I'm using the 18" version and it works well, sealed motor, plastic blades, fiberglass shroud, lots of air movement, and rather quite. You can also get a speed controller. Grainger has specs and sells unit for more than 2x.s the buy it now price

cabnet636
01-20-2009, 06:04 PM
a fan in a spray room booth is called "explosion proof" for a reason! not fire proof nor resistant, 21 years ago i was spraying in the back of what was then my shop, (had no money) i was spraying laquer and simply using a 32" pedestal fan to move the air "BOOM" when it ignites it does not keep blowing in the wind/fan direction it follows the fuel, i got lucky and lost my armhair, eyebrows and most of my hair, nothing ignited beyond that as i was using a hose and the pot was remote. don't mess with this!!!! tommorrow i post some pics of our 1600' booth and two spraybooths with both sprinkler and fire suppression. i have two smaller tube fans and a booth i mught sell, they are perfect for small applications, if you only need a temporary booth you can build a rolling wall line it with galvanized sheet and install a ep fan like graingers, i hope one would notice how hard they are to find and you never see a used one!!! there is a reason for this, if you ignite your house or shop and you insurance finds the fan not ep proof (and they will) you can kiss your claim goodbye

you can find them in poultry barns and automotive applications, the grain industry sell's them as well.

jim mcgrew

cabnet636
01-20-2009, 06:05 PM
ps keep a real good fire extinguser near as well!!

cabnet636
01-20-2009, 06:07 PM
yall got me on this, it is not always the spark or the electrics that start the fire, it is the metal blades!!

Gary Campbell
01-20-2009, 06:17 PM
Gerald...
2nd the explosion proof motor for all the resons above. To acquire the proper size (CFM) fan, take the height and width of the booth. for example, 8' wide 8' high, 64 square ft. multiply by 100 for minimum CFM. 8 by 8 by 20 ft long booth = minumum 6,400 CFM.
Gary

dakers
01-21-2009, 10:02 AM
When i was doing spraying myself i got by on anything i could cobble together that worked. when we started having employees spray that is when i felt the guilt to do it right or suffer the wrath of the authorities and my concious.
i think with fire suppression and everything else we spent about $8,000.00 for a small booth with 24'' 5hp fan. we also had to be in an area zoned for spray painting.
then we had to teach the employees courses in spray painting safety and have them sign off on classes so we could prove we did that. then had them go to medical center to be tested for lung problems to qualify that their lungs were healthy enough to wear paint masks and to have benchmark for any health changes due to spraying. We had to have properly fitted masks and no beards were allowed with masks We had to get air fed mask with hood and oiless compressor for two componet paints. put up posters near booth about safety. keep files of msds available and send copies to fire dept. have the suppression system checked each year and the powder replaced every 3 years. get permits, have drawings made. we had to run wires to ground everything including mixing station and special thinner cans. have special explosion proof cans for rags. have a company come and properly dispose of the solvents we used for cleaning.
the booth had a guage to tell when to change the filters which were expensive too. also had to coat the floor and the sides of booth with rubber stuff so we could peel off paint build up.
we did not get make up air which caused some issues sucking the carbon monoxide from the gas heaters so we opened the garage door and it was cold but safer. had to keep heaters 25 ft from booth with exposed pilot lights, etc.
we also had to have a designated safety person plus a book about a thousand pages with all our safety info for shop.
however i found out in our area it is all about the volume of spraying that determined what had to be done.

It really seemed overwhelming. We have downsized since and i am happier. Things can be so complicated to do everything right and they take more money than it is worth sometimes.

i do think doing the math for the correct cfm for the size booth is important but the filters determine the efficiency also. A friend of mine built his own booth using furnace filters and things are working fine for him. he does not spray more than a gallon every few months.

cabnet636
01-21-2009, 11:04 AM
tauton press has a good video on "spray basic's" i make all employee's watch it, if you are a small shop which all of us are or were then a little prevention can go a long way, were as none is a sure sign of disaster!!

jim mcgrew

waynelocke
01-21-2009, 12:09 PM
You might also consider switching to a water based finish. I have been spraying water base for over ten years partly because of the fire hazard. The fumes are also not as toxic.

A spray booth for water base doesn't require an explosion proof motor and makes the spray booth easier and cheaper to construct.

wberminio
01-21-2009, 12:26 PM
you might want to check this thread out
www.talkshopbot.com/forum/messages/312/37973.html?1232479608 (http://www.talkshopbot.com/forum/messages/312/37973.html?1232479608)

cabnet636
01-21-2009, 08:03 PM
my booth, commercial, we have two booths in a room devoted to spraying


7784

gerald_martin
01-22-2009, 09:47 AM
Thanks everyone.

I took the plunge for an explosion proof fan (see my link above)

It doesn't make sense, I agree, to risk a brand new workshop building on a fan not rated for flammable vapors.

Gerald

s8ft1
02-01-2009, 12:42 PM
Gentleman: Allow me to make a comment. First, I am a 30 year OSHA veteran, retired and now run my own safety and health consulting firm. I am currently working with a client who wants to build/design a "Spray Room". Without getting into much detail, I want to make everyone aware of the fact that the applicable OSHA regulations can be confusing. There are two main concerns with this operation and addressed in the OSHA regs. 1. Health (employee) concerns addressed in both 29 CFR 1910.94 (ventilation) and 29 CFR 1910.1000 (Chemical-Allowable Limits).
2. Safety (building structure-property damage) addressed in 29 CFR 1910.107 (Spray Painting Operations). You have to be very careful in the design and operational procedures. To confuse it a little more, complying with one regulation does not automatically bring you in compliance with the other, and once you ensure the inside is in compliance, you then have to ensure whatever you are dumping outside (ventilating) complies with Local and National EPA regs. Not to confuse the issue, but these are valid concerns you must be aware of. If you have any questions, you can email me at: jpleseganich@msn.com (mailto:jpleseganich@msn.com). I check my email daily, but may not check this site often. Take care.

cabnet636
02-01-2009, 01:11 PM
we contacted osha and were guided by the agency, it does two things 1)compliance is accountable and 2) you are given time to remedy and no fines can be levied, calling for "compliance inspection" was the smartest move for me as no consultant wwould list us a coinsured nor would work with out a disclaimer for his work. kinda like a cpa or attorney. oh and he is right it is not the easiest method but i feel much safer and so does my insurance company

jim