Discussing booths

[secretasianman]

The weather is changing, and for many of us, woodsheds, garages and wide open windows are rapidly becoming less of an option. I noticed some of us (namely our well equipped leader Dr. H, and equally equipped columnist and producer FilmMkr to name a couple) have professional spraying environments which contain spray booths completely facilitated with sufficient lighting and exhaust setups.

I unfortunately like many others have not explored such options until now. My last place of residence was a condo and I recklessly sprayed in my spare bedroom for over a year relying only on windows and the corner cross breeze to keep the environment clean. When I sold the place an obscene amount of paint and primer dust littered the room and carpet and because of the vaulted ceiling there was ample facility for sufficient quantities of dry over spray to migrate throughout the rest of my home.

I've since moved into a house and don't want to repeat the cleaning strategy on exit so I decided I will need a booth if I decided to resume spraying.
I recently inquired with the good Doc my shopping options (dixie all the way, baby) and still have a couple burning questions about what to expect and how to facilitate myself.

In this thread I've showcased my new modeling area: http://gkjapan.com/showpost.php?p=7032&postcount=39 which is relatively tight quarters and probably measures roughly 8x14 feet without the shelf and workbench.

I'm interested in the Artograph 1530 at the bottom of the page here: http://dixieart.com/Artograph_Spray_Systems.html and plan on ventilating (with a inline blower assist) out of what appears to be an old dryer vent exhaust pipe:

http://www.tellyourfriends.org/DSCN2651.JPG

I'm 100% committed to getting the booth but am still have a couple questions about my expectations:


What kind of performance should I expect?
Will there still be fumes and over spray in the immediate surroundings or will this suck everything out of a 3 foot radius?
Will there be staining outside the exhaust vent?


Thank you for your time.

[Dr.H]

Looks like you have the right ideas Secret.

Lets see.. the answers to your questions overlap a bit so I'll just right one answer.

Your performance depends on a couple of things. How much exhaust piping will there be, fan cfm and air flow through filter material.
You mentioned getting the same booth as me the 1530. This booth has 370 cfm which is a lot more air flow than most hobby booths out there but for good reason.
cfm on fans and booths is usually rated at " free or unrestricted" meaning no filter material at all with no exhaust piping attached.

This booth has a really good 3 stage filter system. A thin polyester pre-filter on top to catches most of the thick paint particles(color) and is cheap and easy to replace, in fact the booth comes with a few spares. The second layer is a " 1 inch thick non-woven polyester air-laid material with a blue PVC tackifier binder on the exit side... filtration for particles 5 microns or larger." This will trap the smaller paint particles and will last a pretty long time with the top layer above it.
The third layer is the most important when your thinking of harmful and explosive fumes. The poly-carb filter will trap these super light and small fumes so very little is passed onto you fans and outside. I recommend anyone who has a homemade or store booth that doesn't have this type of filter to add one.

This booth is a 15" x 30" downdraft with two fans mounted right underneath the filters so you will get very little over spray outside of that area if you don't spray to far from the front of the booth. The amount of over spay dust I have around my booth is small enough that I can't tell if it's from spraying or regular dust.

As for straining on the exhaust vent.. The booth has two exhaust vent pipes on it so the air flow is more efficient but it is recommended that you try to have the pipes no more than 8' long if you can help it. I would try to set-up a small table closer to your vent if you can and also try to pop out another of those glass blocks for a second vent pipe.
I'm not sure what type of effect a in-line blower for assist would have. I would worry that it would produce a negative vacuum in the pipes behind the main fans that might reduce their efficiency or possible harm them. I'm not really sure about that so you'd have to find out more info from manufactures on that.

Of course these answers are different for different booths ;).

[DOJO]

Sorry to ask.
I'm building a spray booth now too and read in couple of article online that they make two exhaust pipes. Why two? as I will have only one fan blower and I understand that one exhaust goes into the window and where and why the second go?

[Dr.H]

When there is two exhausts the second one goes though the window too. I suppose it mainly has to do with the amount of velocity that the fan(s) can put out vs there being less static pressure(resistance) in larger piping or in this case two pipes of a common size with easy to find parts.
There is probably a calculation somewhere to figure out pipe size and length to correspond with blower properties.. I'm sure someone working in the HVAC field would know more about this.

[DOJO]

http://www.briansmodelcars.com/tutorials/tutorial.asp?TutorialID=23&CurPage=1
I think this is the best info on the spray booth.

ok, but where does the second pipe goes in to?
As i got one fan, i can have one pipe?

[Dr.H]

It looks like that booth was drawn for two fans but says to on the hole cut out to "center opening for single fan" if the fan is attached to the back of the booth and the pipe is attached directly to the fan then you'll only be using one pipe.

[secretasianman]

That article is an eye-opener. I will now scratch the $30 duct blower I saw at Lowe's off of my shopping list. (centrally mounted fan, open motor) I also wonder if this is why my central heating/cooling unit was shot when I sold my condo too.

[DOJO]

thanks H, as i was getting confused about the two pipes as I could not understand what it was for.

secretasianman that article is great