Spray Booth - Fan Location

[hooterville75]

Im finally ready to mount my Blower Motor and finish up the final stages of my Airbrush Spray Booth. I don't know which draft would benefit me more. I have a Bilge Blower Motor that produces 250 CFM's. Would I be able to put the fan at the top of the spray booth in the middle ? The entire blower motor would be outside of the spray booth other then the fan or I could even put a inch or so of the plastic into the booth as well. Or should I put the blower motor in the back of the booth in the middle ? Again with just the fan in the booth or part of the plastic in the booth ? Should I put the blower motor in the side of the booth ?

If I need to have an additional blower motor which I do have if needed although its a OLD blower motor (Which does work, tested again today) but don't know the CFM's. I would rather stick to one motor as I dont have the second dryer duct vent. I don't know if its possible to T off the dryer vent I already have or not but if so I could do that that both vents blow out the same place. Would like to work on this tomorrow so any help asap would be greatly appreciated. Thanks in advance for any help, advice or recommendations.

[Art Anderson]

I assume that your blower is of the "squirrel cage" type (just as with the blower for your furnace)? If so, mount that behind your spray area, with a good quality fiber element furnace filter in front of it, so that paint overspray gets trapped in the filter, and not allowed to coat the turbine of your blower, the inside of your vent duct, and as a sidelight, not stain the outside of your house. This is, BTW, how PACE builds their spray booths.

Why the furnace filter IN FRONT of the blower turbine? Simple: Your goal with this exhaust system should be two-fold. First of course, you want the solvent fumes to go out of your work area (they aren't the best stuff to breathe, and are a fire/explosion hazard), and second, to remove the particulates (dried overspray) from your work room, while keeping them from lining the ductwork that directs the fumes to the outdoors. Paint overspray dust coating the inside of such a duct is potentially hazardous--it only takes a spark of static electricity, and that stuff can explode into flame in a NY Minute (just ask anyone who's seen or experienced an air duct fire in a factory or body shop (they do happen), and the cost of that air filter is FAR cheaper than repairing or replacing your house (and certainly less expensive than repairing YOU!). A $5 furnace filter will last for several model car paint jobs, which makes it cheap insurance (and keeps your wife or significant other happier as well).

Art

[CadillacPat]

Hooter I received your Private Message with a copy of your questions so instead of responding twice I guess i'll just answer it here to benefit everyone.

I appreciate your comments saying my written Tutorials on this subject looked to be the best way to go.

Im finally ready to mount my Blower Motor and finish up the final stages of my Airbrush Spray Booth. I don't know which draft would benefit me more. I have a Bilge Blower Motor that produces 250 CFM's. Would I be able to put the fan at the top of the spray booth in the middle ? The entire blower motor would be outside of the spray booth other then the fan or I could even put a inch or so of the plastic into the booth as well. Or should I put the blower motor in the back of the booth in the middle ? Again with just the fan in the booth or part of the plastic in the booth ? Should I put the blower motor in the side of the booth ?

Place your fan in the back wall of the Booth. This will put the fan in the most direct path of the spray coming from your airbrush.

Make sure the blades of the fan are flush or just below flush with the inside surface of the wall.
If I need to have an additional blower motor which I do have if needed although its a OLD blower motor (Which does work, tested again today) but don't know the CFM's. I would rather stick to one motor as I dont have the second dryer duct vent. I don't know if its possible to T off the dryer vent I already have or not but if so I could do that that both vents blow out the same place. Would like to work on this tomorrow so any help asap would be greatly appreciated. Thanks in advance for any help, advice or recommendations.

Sure, two motors will work even better but just run out two separate ducts instead of trying to combine them into a T, that would only impede airflow.

These kinds of homemade table top Paint Booths are easy to make, work fine, are easy to change the motors out of, and will take your painting skills to the next level.

I recommend not using any kind of filters in front of the fan blades. That's only cutting off your air supply to the fans. I don't use filters.

Since 1999 my Paint Booth has been used every day for hours, and I've shown many others how to build their own inexpensively.

There is no need to worry about dust, static electricity, real electricity or anything else causing explosions.

If you are using Gasoline for paint or using Natural Gas as your compressed propellant, then a tiny infinitesimal spark might be a problem.

13 years now and all the motors that have been in my Booth have yet to produce a spark, static electricity or Nuclear reaction.

Make sure your wiring is correct and you'll never have a problem.

We actually had a Professor in Chemistry on another site weigh in how the spray emitting from an AirBrush cannot be ignited with a "nearby" sprark.

If you have more questions just PM me again or just post your questions on the board.

If you build your own Paint Booth you'll get a much better product than anything you can buy.

Enjoy your booth and use it often, I do mine.

[hooterville75]

Very good and thanks to all for commenting. Time to go get busy. My wiring is a nice part of the situation as its only two wires. The twelve volt rail wire and a black ground wire. With the lab bench power supply I've converted from the ATX power supply the wires are identical in color. 12 Volts rail is yellow and the ground is black. Im going to take your suggestion and not use the filter as its an added expense that I don't really feel is needed. Once I have the booth finished, Ill be taking pics to post. Thanks again for the information. Im hoping to have this finished by the end of the weekend.

[Art Anderson]

Very good and thanks to all for commenting. Time to go get busy. My wiring is a nice part of the situation as its only two wires. The twelve volt rail wire and a black ground wire. With the lab bench power supply I've converted from the ATX power supply the wires are identical in color. 12 Volts rail is yellow and the ground is black. Im going to take your suggestion and not use the filter as its an added expense that I don't really feel is needed. Once I have the booth finished, Ill be taking pics to post. Thanks again for the information. Im hoping to have this finished by the end of the weekend.

I for one do believe that the filter is key, and very important to use. Please consider it. Overspray particulate is probably the biggest risk for fire over time.

Art

[Art Anderson]

Hooter I received your Private Message with a copy of your questions so instead of responding twice I guess i'll just answer it here to benefit everyone.

I appreciate your comments saying my written Tutorials on this subject looked to be the best way to go.

Sure, two motors will work even better but just run out two separate ducts instead of trying to combine them into a T, that would only impede airflow.

These kinds of homemade table top Paint Booths are easy to make, work fine, are easy to change the motors out of, and will take your painting skills to the next level.

I recommend not using any kind of filters in front of the fan blades. That's only cutting off your air supply to the fans. I don't use filters.

Since 1999 my Paint Booth has been used every day for hours, and I've shown many others how to build their own inexpensively.

There is no need to worry about dust, static electricity, real electricity or anything else causing explosions.

If you are using Gasoline for paint or using Natural Gas as your compressed propellant, then a tiny infinitesimal spark might be a problem.

13 years now and all the motors that have been in my Booth have yet to produce a spark, static electricity or Nuclear reaction.

Make sure your wiring is correct and you'll never have a problem.

We actually had a Professor in Chemistry on another site weigh in how the spray emitting from an AirBrush cannot be ignited with a "nearby" sprark.

If you have more questions just PM me again or just post your questions on the board.

If you build your own Paint Booth you'll get a much better product than anything you can buy.

Enjoy your booth and use it often, I do mine.

Pat, while I certainly respect your skills, and your expertise, trust me (as one formerly responsible for fire safety in a manufacturing plant, paint particulates, once collected in the ductwork of any exhaust system, IS a major source of fire hazards. That information comes from none other than Liberty Mutual Insurance Company, who specialize in commercial and industrial fire and casualty insurance.

Art

[CadillacPat]

Pat, while I certainly respect your skills, and your expertise, trust me (as one formerly responsible for fire safety in a manufacturing plant, paint particulates, once collected in the ductwork of any exhaust system, IS a major source of fire hazards. That information comes from none other than Liberty Mutual Insurance Company, who specialize in commercial and industrial fire and casualty insurance.

Art

Yeah Art, we certainly want to believe those Insurance Companies now don"t we!!!!!!

How about we just leave our whole society in the hands of the Govt and the Insurance Companies and let them take care of us.

All that Fire Hazard Safety stuff is just another way to tax and scare us.

Jesus., we are talking about AirBrushing, not firing up the Concorde in a room full of Gunpowder.

Art, trust me, experience speaks for itself, these Paint Booths do not explode.

I suggest you search the Internet for catastrophic life changing explosions due to AirBrushing.

[Art Anderson]

Yeah Art, we certainly want to believe those Insurance Companies now don"t we!!!!!!

How about we just leave our whole society in the hands of the Govt and the Insurance Companies and let them take care of us.

All that Fire Hazard Safety stuff is just another way to tax and scare us.

Jesus., we are talking about AirBrushing, not firing up the Concorde in a room full of Gunpowder.

Art, trust me, experience speaks for itself, these Paint Booths do not explode.

I suggest you search the Internet for catastrophic life changing explosions due to AirBrushing.

Pat, you miss my point.

While of course I referred to Liberty Mutual, but the annals of industries where spray painting is used are filled with anecdotes of fires from accumulated dried paint dust--autobody shops, furniture factories, cabinetmakers, the whole gamut. Not to mention, the accumulation of overspray in one's house, messy of course, and stains on the outside of the house at that. For the small price of a decent quality filter, why risk tens of thousands of dollars in potential damage, not to mention the lives involved?

Also, bear in mind that not just a few members here live in apartments--landlords will not take kindly to paint overspray dust all over once a tenant moves out. Things to consider, methinks.

Art

[hooterville75]

While I respect all answers given to this post I have a few cents to add in regards to the filter. I don't disagree with anything you said Mr. Anderson. While I believe from a liability standpoint there's all truths to your responses. On the other hand I have to agree with that Pat is saying as it would take a whole lot of over spray and dust to ignite a little booth like this. I believe the amount of airflow that Ill have flowing through my spray booth will be way sufficient to cause a fire. I am lucky enough to have my dryer vent vented to a crawl space outside on the ground, under an addition that was built to my house a few years back. My venting is short with maybe seven feet (that's on the larger side) period to the crawl space outside. I feel that I will be safe without going with a filter.

I've heard a lot of mixed stories in regards to the filters. I kind of determined that I wouldn't use a filter when I found out that peg board would hurt my airflow in the spray booth if used. I feel if peg board will hurt my airflow then a filter would as well. I want to have the proper airflow going through the spray booth at all times with no interruptions to its performance.

I kind of view it like this. Even if I were to use a filter in my spray booth, I feel the amount of over spray or dust that would escape through the filter is minimal enough that a fire would never start. Its the same way I feel as if I don't use a filter the amount of over spray or dust that gets into the vent is minimal enough to not worry about a fire.

I hope you can understand how I feel about it all and that I'm not disagreeing with either of your posts and fully understand where both of you are coming from. Thanks again for the responses. I truly appreciate your help.

[mikemodeler]

Keep in mind that everyone is entitled to their opinions but when you come on a forum and ask a question, prepare yourself for differing responses. The subject of homemade vs. manufactured spray booths is a very touchy topic here on this forum.

If filters were not deemed important, than I don't know why they are made. The mist from an airbrush is quite fine and probably poses little threat but depending on what else you spray in that booth (rattle can or automotive grade paints/clears or urethanes), having a filter may make a difference. Again, it is your choice so whatever you decide is on you. The concept of a filter before the fan is keep the particles from being emitted downstream or into the outside atmosphere and if the fan is of sufficient CFM, it should not affect the paint job.

[CadillacPat]

Pat, you miss my point.

While of course I referred to Liberty Mutual, but the annals of industries where spray painting is used are filled with anecdotes of fires from accumulated dried paint dust--autobody shops, furniture factories, cabinetmakers, the whole gamut. Not to mention, the accumulation of overspray in one's house, messy of course, and stains on the outside of the house at that. For the small price of a decent quality filter, why risk tens of thousands of dollars in potential damage, not to mention the lives involved?

Also, bear in mind that not just a few members here live in apartments--landlords will not take kindly to paint overspray dust all over once a tenant moves out. Things to consider, methinks.

Art, if someone is sitting in an apartment and venting their PaintBooth right back into the same room, then I have no advice for that person. I offer help to people capable of using it.

Art

Art, the scope of this continues to escape you.

You keep referring to industrial spray painting and the discussion is about AirBrushing,--------- AirBrushing --------- it's about AirBrushing!!!!!!!!!!!!

This atmosphere you keep referring to that is filled with dust particles, paint particles, large amounts of volatile liquids, does not apply here.

If you must use filters, for whatever your reason, then go ahead, but from experience I suggest not using them because I don't.

Oh, never mind!!!!!!!!!!!!!!!!!!!!!!!!!

[Guest G Holding]

Pat...Art knows far more than you....Respect the man and message.If filters are not needed...then why does EVERY booth have them? I also have ignited lacquer from the A/B...on purpose...it does flame! Deron....you life and safety are important...spend a few bucks and do it correct

[Art Anderson]

Art, the scope of this continues to escape you.

You keep referring to industrial spray painting and the discussion is about AirBrushing,--------- AirBrushing --------- it's about AirBrushing!!!!!!!!!!!!

This atmosphere you keep referring to that is filled with dust particles, paint particles, large amounts of volatile liquids, does not apply here.

If you must use filters, for whatever your reason, then go ahead, but from experience I suggest not using them because I don't.

Oh, never mind!!!!!!!!!!!!!!!!!!!!!!!!!

Then, why, oh why, do commercially built airbrushing spray booths come with filters? Hmmmmmmm?

Better safe than extra-crispy, my friend.

Art

[CadillacPat]

Then, why, oh why, do commercially built airbrushing spray booths come with filters? Hmmmmmmm?

Better safe than extra-crispy, my friend.

Art

Art, that $200 to $400 commercially available hobby paint booth you refer to is 20% value and 80% profit for the company.

You get a 10 cent filter as nothing more than window dresing or swag to give the appearance of value.

Why do you think people prefer to build their own??

I'll see your extra crispy (the sky is falling afain, oh my God) and raise you 13 years of safe, satisfied and daily use in not only my own PaintBooth but those I've assisted others in building.

[CadillacPat]

Pat...Art knows far more than you....Respect the man and message.If filters are not needed...then why does EVERY booth have them? I also have ignited lacquer from the A/B...on purpose...it does flame! Deron....you life and safety are important...spend a few bucks and do it correct

Greg, I'll appoint you Person In Charge Of Knowing What Other People Know Instead Of Posting What He Knows, If He Does Know!!!!!!!

Kind of like the Amazing Criswell.

I suggest you respect the information that the rest of us are posting, it's your's free for using.

Obviously you have not seen every Paint Booth Greg, because Every Paint Booth does not have filters, as has been stated in threads just like this, over and over and over.

Greg, do you have pics of the Paint Booth you are using??

[Guest G Holding]

Artograph 15 x 30 ....Better check Mr Anderson out....he knows a bit...

Edited December 1, 2012 by G Holding

[CadillacPat]

Artograph 15 x 30 ....Better check Mr Anderson out....he knows a bit...

Greg, I don't believe you are using that Booth. That's just a pic you grabbed of the Net.

But, never mind, I've already given the necessary info to the originator of the thread, Hooter.

Greg, you and Art can have the thread now to do as you wish.

[hooterville75]

Keep in mind that everyone is entitled to their opinions but when you come on a forum and ask a question, prepare yourself for differing responses. The subject of homemade vs. manufactured spray booths is a very touchy topic here on this forum.

If filters were not deemed important, than I don't know why they are made. The mist from an airbrush is quite fine and probably poses little threat but depending on what else you spray in that booth (rattle can or automotive grade paints/clears or urethanes), having a filter may make a difference. Again, it is your choice so whatever you decide is on you. The concept of a filter before the fan is keep the particles from being emitted downstream or into the outside atmosphere and if the fan is of sufficient CFM, it should not affect the paint job.

Mikemodeler where do you see me ranting or raving about any post that is posted on this thread ? I was very polite to all involved, took all responses into consideration in regards to making the decision of if I will use a filter or not and thanked everyone for there opinions. I was very well prepared for the responses I got and appreciated all of them. I'm very confused as to where your first paragraph came from. I appreciate the explanation of the filter and its purpose along with the other information you've provided. Thanks again, Ill continue to do a bit more research of the filter and make my decision from there. Thanks again to all who responded to this post. Lets not let this get out of context. Thanks again and enjoy the rest of your weekend. Happy building.

[VW Dave]

I need to shoot a new pic of it, but my homebuilt booth utilizes a brushless fan and we built it to accept the same size filter as my furnace; after initial testing it was converted to downdraft, and I've been very happy with it.

[hooknladderno1]

I too am in the process of building a spray booth. I am building a down draft style booth. Just a suggestion for those considering doing so: I utilized a section of open grid that is commonly found on flourescent lights. It is open, but still strong enough to support a large model and stand. It allows much more flow through than either pegboard or randomly drilled holes. They are easily found at most home improvement stores and simple to cut to shape. I used my rotary tool(Dremel). I chose to put a filter in mine, as I am currently in an apartment. I have a few more steps to go before it is operational.

Edited December 3, 2012 by hooknladderno1

[Guest G Holding]

Great tip David! I wish my booth had that, as I have a down draft with a top filter that clogs by looking thru it. It is by design, I may try a bit of that on top for stability.

[dmk]

Here's my home built booth. It has a downdraft squirrel cage fan, outside vent, and I use cheap furnace filters at the base of the booth, over the fan. I have no issues with airflow. I use spray cans in here all the time. It's hard on the filter, but there is no smell in the room at all.

The downdraft pulls the paint and dust down. I felt this was the best for me, seeing as I generally paint from an angle above and to the right. I thought rear draft might pull dust across the model and might also pull paint from the brush to the rear away from the model.

The inside is painted gloss white with under cabinet lights mounted at top. I later added a gooseneck reading lamp attached to the top for more light.

There is a clear acrylic door held closed with a magnet. After painting I can leave the model in there to dry, protected from dust and accidents.

Under the baking rack is a cheap furnace filter and a large square plenum area under it. It pulls enough air to use a spray can in there without any paint smell in the room, but that will foul the filter quickly. Luckily they are cheap and very easy to replace.

Here's the 400CFM squirrel cage fan on the bottom under the plenum.

It exhausts out the window. There is a dryer vent on the outside that closes automatically when the fan is off.

Blower and light switches. Low cost hardware store compressor with 5gal air tank underneath.

I was later able to fit plastic storage drawers between the switches for pipettes, neoprene, gloves, Q-tips, and various other things I use while painting.

Edited December 6, 2012 by dmk