Tell me about spray booths. What should I be looking for? What's

I have this one, minus the extra hose.

I honestly mostly got it because I wanted a solid booth to spray in which, if necessary, can be folded into something smaller. The piece in the middle can be rotated or completely removed; I removed mine and use it instead to photograph finished pieces since the rotating feature is pretty useful for this.
It's...medium loud? Sounds like the exhaust hood above a regular stove, just a little quieter.

Since my parts are usually pretty small the booth is big enough. I also don't spray big pieces/have to cover large surfaces, so the sprayed amount of paint at once is not much.
However, I cannot say if it actually helps better than any other box.
You cannot feel any "wind" and any paint that is on the filter is probably there because I blow the paint into the general direction of it anyway. I have never sprayed without it so I got no experience with some cardboard box setup.

>>6313212
Speak with gunpla and the scale model generals for faster and wider variety of opinions

>>6313222

I think it sounds like half a vacuum cleaner.

File: s-l500 (3).jpg (1B, 486x500px)

1B, 486x500px

Ooh, this one has lights.

>>6313212

I made one out of plastic sheeting, computer fans, a rotostand from an old tv and a tumble dryer tube.

Everything was salvaged, it was free, and assembled in a weekend.

I'm probably dumb and don't know much about spray booths since the only ones I've used were big ass ones in my highschool, but wouldn't that just blow paint fumes into your face? Or does it suck in from the part at the top?

>>6313785
bless your sweet little heart

>>6313212

I built one with filters for less than fiddy.

Just pick an exhaust fan from home depot and shove it in any plastic box with a hole in it. Add filters if you feel like.

>>6313785
what are flexible hoses for 100, Alex?

>>6313785

It blows it away from you, not back into your face

>>6314200
I think >>6313785 is confused because the hose loops back to your face on the picture.

>>6313785
The stuff gets sucked in through the blue filter, and in the back you have an exhaust opening. You can add the hose pictured and place its end towards a window for example.

I honestly don't know if the hose actually helps. The filter doesn't seem to suck up enough air to even have something end up going through the hose.

>>6314228

With the hose, at least with the version I have, you are supposed to use 1x filter instead of the 2 it comes with by default. Airflow might be better with 1x filter, but that's just a guess.

I still think the hose is useful if you use something like lacquer paint.

File: centrifugal_fan.jpg (34KB, 365x357px) Image search: [Google]

34KB, 365x357px

>>6314228
>I honestly don't know if the hose actually helps. The filter doesn't seem to suck up enough air to even have something end up going through the hose.

The hose doesn't appear to be helping because that Badger spray booth appears to have the the wrong kind of fan for the purpose. It uses an axial fan, which moves air at a high rate but at *low pressure.* It needs a centrifugal fan. See pic.

A spray booth needs to have a properly rated centrifugal fan which moves air at higher pressure in order to overcome the static pressure created in a restricted air system. Any amount of flexible hose makes the problem even worse due to greatly increased turbulence.

>>6314228
Yea I figured that since both the pictures have the hose pointing back at you that it was meant to be like that.

>>6313212
>Best one
If in the US:
http://pacepaintbooths.com/pace/Products.htm
I have the 24 Mini Plus and itdoes the job well. Costly at the $300 range shipped but has yet to fail me.

>>6313212
What the fuck is a spray booth?

>>6314896
Something to provide air circulation and filtration, my brain damaged friend.

>>6313737
Okay McGuyver.

>>6315150
what the fuck is circulation and filtration?

>>6314272
Is a spray booth without one of those totally useless then? I'm not sure how to get one with a centrifugal fan around here, and I don't think I know how to mount one myself.

>>6315379
It's when Solid Snake has to go -around- the base before he sneaks in.

>>6314272
Wouldn't an explosion-proof centrifugal fan blower cost hundreds of dollars just on its own?

>>6316011
>Is a spray booth without one of those totally useless then?

Not totally useless as axial fans may be strong enough to pull atomized paint particulates and VOCs into a filter medium and away from the operator. However, the problem is that no consumer-grade filter is going to be 100% effective at removing everything, so there's going to be some toxic particulate and compounds in the outgoing airflow.

The problem with axial fans is that when they lack the pressure to fully evacuate contaminated air from the workspace, the toxic particulate and VOCs accumulate in the duct work where the airflow significantly slows down, allowing them to leak back into the room. If you use a portable spray booth, disturbing the exhaust hose when you put the booth away can disperse the atomized paint particulate back into the air inside the room.

> I'm not sure how to get one with a centrifugal fan around here, and I don't think I know how to mount one myself.

Centrifugal fans aren't difficult to mount. They have screw holes in the fan casing surrounding the air intake and the fans usually come with a mounting flange. You may need to get longer screws to accommodate the thickness of the wall of your spray booth.

You may be tempted to use bathroom ventilation fans sold at big box hardware stores because they're easy to find and less expensive. But I've found that it's difficult to find bathroom ventilation fans with sufficient static pressure ratings that are good enough for spray booths. Additionally, bathroom fans typically have their electric motors mounted within the airflow. If you spray solvent-based paints, solvent can build up on the motor windings and eat away at the windings' protective enamel coating.

>>6316140
>Wouldn't an explosion-proof centrifugal fan blower cost hundreds of dollars just on its own?

You don't need explosion proof fans for hobby spray booths. If you're doing automotive finishing, spraying full size vehicles, that's one thing. But the intermittent use of your small airbrush won't be producing flammable vapors at sufficient volumes to reach the parts-per-million density that is required for an explosion.

However, it's still best practice to use a centrifugal fan that's mounted outside the outgoing airflow.

>>6317216
>However, it's still best practice to use a centrifugal fan that's mounted outside the outgoing airflow.

Clarification: It's best practice to use a centrifugal fan *where the electric motor* is separated from the outgoing airflow.

>>6317227
How would a lay person be able to spot one that is separated?

I was going to just use an overhead stove fan with moderate CFM for a spray booth project, but the centrifugal fans that you've brought up seem more effective and cost about the same for a bare unit. I'm not a machine person, so I'm not seeing a physical difference between any of the models I'm looking at online regarding separation of parts from airflow.

File: which_centrifugal_blower_to_use.jpg (1B, 486x500px)

1B, 486x500px

>>6317655

>How would a lay person be able to spot one that is separated?

I composed this graphic that I hope is clear. The fans outlined in red are ones that you should avoid. They clearly have their motors mounted in the path of the incoming air flow. If they're used for a spray booth, there's the strong possibility that paint and solvent can build up on them.

The fans with their motors mounted outside of the air flow typically have a protrusion extending out from the fan housing, as noted in the upper left green box.

>I was going to just use an overhead stove fan with moderate CFM for a spray booth project

I suggest not using an overhead configuration for a spray booth. First, an overhead exhausted spray booth has to work against gravity, so you need a more powerful and thus expensive fan. Also, because the filter is above the piece you're spraying, there is a chance that loose particulate can fall onto your paint job unless you remember to remove the piece you're spraying before you shut off the fan.

I recommend either a cross draft configuration where the fan is mounted at the back of the spray booth or a down draft spray booth where the fan is mounted in the floor of the spray booth. The down draft spray booth lets you get away with a less powerful (thus less expensive fan) due to being able to take advantage of gravity.

Check out this page on spray booth design. It's pretty helpful and covers fan location, calculating static pressure, flow rate etc.

http://www.modelersite.com/Abr2003/english/Spray-booth-design_Eng.htm

>>6317831
Unless the motor is actually sealed and/or a brushless DC motor it's not actually going to be that much safer. And for what it's worth, sealed brushless DC motors are used in industrial settings all the time.

>>6314272
>The hose doesn't appear to be helping because that Badger spray booth appears to have the the wrong kind of fan for the purpose. It uses an axial fan, which moves air at a high rate but at *low pressure.* It needs a centrifugal fan. See pic.

You don't need to operate under high pressure to exhaust paint particles... Most of the paint should be caught by an initial filter anyway and the only thing the fan has to defeat is a fairly breathable air filter, which are porous enough to allow mild airflow.

More importantly, people misinterpret what exactly the static pressure reading is supposed to be. It's flow when the fan is in a pressurized environment. While it's generally true that being able to operate under high pressure also means it's able to draw heavier gasses so to speak it's not really necessary in most cases. Usually fans that operate under high pressure are expected to work in an industrial environment where the fans meet resistance like being bombarded by water or oil, or even submerged.

With aerosolized paint you probably don't need to worry about it too much as long as you get good flow through the filters. You're already shooting it towards the exhaust fan and even with wet coats it's not like you're trying to shoot water at them.

>>6317854

>Unless the motor is actually sealed and/or a brushless DC motor it's not actually going to be that much safer.

When motors that aren't mounted within the air stream at all, they are there's no chance for any vapour to actually reach the motor before the vapours are exhausted, and there's no chance for paint or solvent residue to build up on the motor components.

>>6317912
But that's not true. The air stream isn't some sort of contained stream that nothing escapes from, the motor is just out of the way but there's always a present danger of air, among other things, leaking into the motor's compartment. I'd even say it's guaranteed to happen unless it's sealed, and you're unlikely to find a sealed motor blower for under a few hundred dollars. The reason why they mount motors outside on blowers like that is because they're usually for some high-heat operation so the motor doesn't degrade due to hot air streaming through it 24/7 and you can potentially cool the motor in a different environment.

Like I mentioned before unless it's sealed and/or brushless I don't see it being that much safer if you want the peace of mind. And you don't really need the pressure. Personally I'd recommend a sealed bilge blower if you can stand the noise. They're loud as banshees but many are sealed against particulates and liquids which will help and they're made to operate under fairly high pressure, not to mention most move a good amount of air. If it's too loud then there are several industrial-grade versions of server fans that are also sealed and move decent air. Good part about these options is that they're typically DC brushless and they're cheap (30-40 USD) so you can replace them often if you need to. And you can run them from any old 12 (or 24V if that's your thing) power supply you might have lying around, like an older laptop power supply or a wallwart, you just have to crimp them with uninsulated ferrules or whatever floats your boat and you won't ever touch mains wiring.

>>6317902
>You don't need to operate under high pressure to exhaust paint particles... Most of the paint should be caught by an initial filter anyway and the only thing the fan has to defeat is a fairly breathable air filter, which are porous enough to allow mild airflow.

There's more to it than just pulling paint particulate through a porous air filter. If that's all that is needed, then almost any axial fan will do the trick. It's what happens after the air passes through the filter that's usually overlooked and underestimated.

As was already stated, no hobby spray booth filtration system will be absolutely 100% effective. There will be micron sized paint particulate and VOCs in the outgoing air stream that needs to be removed from the work area and this is where the exhaust duct work comes into play. The spray booth fan has to be able to move the air with enough pressure through the duct work to ensure everything is completely evacuated and this is usually what's overlooked in a lot of cheap or DIY spray booth designs. The use of flexible duct just exacerbates the problem.

>>6318005
You're right, I did forget about the duct but even then 2-3ft of duct doesn't really require a fan that works under very high pressure. A bathroom fan that operates under a few times the max pressure of a PC fan is expected to go through several meters of ductworkand they still work just fine for much larger capacities than a box that's maybe 2 cubic feet.

All I'm say is you guys are massively overthinking the issue here. This is exhausting a bit of paint and fumes from a tiny box, not venting a room full of heavy gasses or something.

>>6317999
>But that's not true. The air stream isn't some sort of contained stream that nothing escapes from, the motor is just out of the way but there's always a present danger of air, among other things, leaking into the motor's compartment.

With a properly rated fan providing suction and the spray booth enclosure constricting the incoming air, and the operator working within the confines of the booth, there's just no way for any contaminated air to work against the air flow, then work its way around the spray booth enclosure and come into contact with the motor.

If any sprayed product is able to escape or circumvent the booth, then you're either working too far from the booth, or your fan is underrated, or you are spraying product at such volumes that it is overwhelming the fan's performance.

>>6317999
>sealed bilge blower
Like this?:
https://www.amazon.com/Marine-Electric-Bilge-Blower-130cfm/dp/B00F7ANK7S

>>6318037
>then work its way around the spray booth enclosure and come into contact with the motor.
There's an opening on the inside for the motor shaft to attach to the cage. When a motor is outside of the airflow it's just out of the path of air generated by the cage, the motor still has to be physically connected to the cage which requires an opening to the motor, which is why an industrial fan would have a sealed motor.

>>6318038
It does say sealed against moisture but I'm pretty sure they have better ones that are submersible or at least watertight. I'd look around more. And keep in mind they're seriously screaming loud.

>>6318045
The submersible ones seem to all have 90 degree turns from intake to outflow, wouldn't that be troublesome for evacuating something like particles through the air air?

>>6318021
>You're right, I did forget about the duct but even then 2-3ft of duct doesn't really require a fan that works under very high pressure.

Flexible duct is very restrictive when it comes to air flow due to interior turbulence, so using just "2 to 3 feet" of flexible duct would be roughly equivalent to using 12 to 15 feet of straight duct. And then your fan performance would have to be rated accordingly. Air flow performance is made even worse if the flexible duct has to make a bend or change direction.

>A bathroom fan that operates under a few times the max pressure of a PC fan is expected to go through several meters of ductworkand they still work just fine for much larger capacities than a box that's maybe 2 cubic feet.

Bathroom fans only need to move odors and moist air which is not a health hazard. If they don't perform optimally, it's not a big deal if some moist air or bathroom odor lingers in the system. But performance becomes more crucial and more demanding if you need to ensure that paint particulates and VOCs, which are more of a significant health hazard, are completely evacuated from the system.

>All I'm say is you guys are massively overthinking the issue here. This is exhausting a bit of paint and fumes from a tiny box, not venting a room full of heavy gasses or something.

Actually, you're not just venting "a tiny box" and this is always the misconception that every hobbyist has with a spray booth. The whole system including the type and length of duct work used to exhaust the booth has to be taken account as well. Massively under-thinking the issue tends to be the usual problem.

I'm not advocating that hobbyists need to build a clean room system worthy of the CDC. The point of all this is to explain that people typically choose the wrong kind of fan for this purpose because they fixate on the filtration side but don't account for the requirements needed on the exhaust side of the system.

>>6318070
Bilge blowers are made to vent combustible fumes so if the reviews say they're using it in the engine compartment it's a good sign and they're alive it's a good sign. But it's unlikely for a DC brushless motor to spark once it's working anyway.

>>6318072
>Flexible duct is very restrictive when it comes to air flow due to interior turbulence, so using just "2 to 3 feet" of flexible duct would be roughly equivalent to using 12 to 15 feet of straight duct.
Then just don't use flexible ducting, it's much easier and cheaper to work around than buying a high-end fan.

>Bathroom fans only need to move odors and moist air which is not a health hazard. If they don't perform optimally, it's not a big deal if some moist air or bathroom odor lingers in the system. But performance becomes more crucial and more demanding if you need to ensure that paint particulates and VOCs, which are more of a significant health hazard, are completely evacuated from the system.
My point was that you have completely overblown needs for this. Bathroom fans have mediocre airflow, rated for a bit higher pressure and they handle rooms and twisted ducts fine, even when they're mounted updraft. Even including ducts a hobby spray booths has like tiny fraction of the volume of a bathroom.

>Actually, you're not just venting "a tiny box" and this is always the misconception that every hobbyist has with a spray booth. The whole system including the type and length of duct work used to exhaust the booth has to be taken account as well. Massively under-thinking the issue tends to be the usual problem.
>I'm not advocating that hobbyists need to build a clean room system worthy of the CDC. The point of all this is to explain that people typically choose the wrong kind of fan for this purpose because they fixate on the filtration side but don't account for the requirements needed on the exhaust side of the system.
In that case I'd still recommend a bilge blower over a mystery squirrel cage blower.

>>6318102
>My point was that you have completely overblown needs for this.

Considering that VOCs are neurotoxins that cause permanent damage to the nervous system and paint particulates cause pulmonary fibrosis, protecting one's health isn't an "overblown" need. I'd rather have a spray booth that has a blower whose performance exceeds minimum safety requirements when it comes to evacuating crap that has a permanent effect on my health.

The blower I have isn't anything high end or fancy. It's a general purpose model 459A blower that costs around $100. It does 265 CFM but more importantly it can maintain 130 CFM @ 0.5 inWG static pressure so restrictive duct work isn't a problem. It's also easier on the ears at full speed than a bilge blower.

While I don't believe in going nuts with safety measures, I also don't believe in going rock bottom dirt cheap with them either. We're not going to see eye to eye so I'm just going to agree to disagree and leave it at that.

>>6318580
>It's a general purpose model 459A blower
A quick search shows that it's a mains powered blower. If safety is a concern then immediately it should be noted that wiring mains electricity is very dangerous and much more likely to get you killed than DC 12V that you find with bilge blowers or server fans. And with a metal casing you must ground them properly. That's a huge concern right off the bat and if electronics were the hobby in question I wouldn't say anything but people just want to blow paint, not deal with hazardous wiring. If it's prewired then that's fine, but if it's not expecting uneducated people wire mains is a potential immediate hazard.

And if inWG is inches of water then a good bilge blower will maintain that airflow at a higher pressure from the spec sheets I'm seeing. If it's really necessary there are even squirrel-cage/blower type bilge blowers that will run on 12V at even higher pressures, though they seem to be rarer and will probably be even louder.

Also, I'm pretty sure even if it's "brushless" (couldn't verify this) an AC brushless motor would be different from a DC brushless motor just by virtue of AC vs DC operating differently. AFAIK DC brushless motors are more likely to be found in industrial settings where the safety might be needed so a DC brushless motor sounds like a safer choice over any AC motor, since it's just more reputable.

>While I don't believe in going nuts with safety measures
Well besides just going overboard I don't think it's actually decisively safer. There are trade offs to go with a blower like that.

>>6319041
>If it's really necessary there are even squirrel-cage/blower type bilge blowers that will run on 12V at even higher pressures, though they seem to be rarer and will probably be even louder.
I can't seem to confirm if they're actually DC brushless, though long-life and continuous operation claims suggest that they are brushless, so maybe that's not a good idea. But regular, axial bilge blowers seem to be the ideal, you just have to put up with noise for it.