JimReed

Spray Room Design

11 posts in this topic

I am finishing up the rough design of my new workshop that I am putting in a 1,000 sq ft garage. I have left an 8 X 10 space for a dedicated spray room. I am a newbie and know diddly about spray room design so I am looking for some recommendations.

My plan was to put a two 3' doors as a French door in one end with drop-in filters in the doors and then put a wall-mounted exhaust fan in the other end which is an exterior wall. I don't have a clue what size will be required for the exhaust fan. I also know some say you absolutely need an explosion proof fan while others say they have been just fine with a conventional fan. Sooooooo, please let me know your thoughts (including how you would optimize the interior of this room-- fixed bench or fold down, work holding/hanging ideas, etc.)

Jim

Share this post


Link to post
Share on other sites

If I was going to use a room I'd use a false wall like a real booth. My booth is made compliant. If you run over to their web site there is a pic that shows the back filter wall as a wire frame photo.

Don

Share this post


Link to post
Share on other sites

The explosion proof fan is most critical if you spray anything other than waterbased products. I plan on utilizing some rubber walls on pivoting barn door hardware. When I get around to building it, I'll be sure to blog it, too.

Share this post


Link to post
Share on other sites

Bob Flexner talked once about making a fan that eliminated the explosion issue. The blade is on an axel with a pulley. The other end of the pulley is on a motor, out of range of the path of flammable material. This eliminates the fire issue and it also makes it cheaper to change fan blade if it gets covered with finish.

Share this post


Link to post
Share on other sites

Bob Flexner talked once about making a fan that eliminated the explosion issue. The blade is on an axel with a pulley. The other end of the pulley is on a motor, out of range of the path of flammable material. This eliminates the fire issue and it also makes it cheaper to change fan blade if it gets covered with finish.

Excellent idea, kinda like the old style pubs have for flashy fans.

Share this post


Link to post
Share on other sites

Jmadson, I like the fan blade with belt to a remote motor!

Dwacker, I don't know what you mean by a "false wall like a real booth", can you explain for this newbie?

Jim

Share this post


Link to post
Share on other sites

Jmadson, I like the fan blade with belt to a remote motor!

Dwacker, I don't know what you mean by a "false wall like a real booth", can you explain for this newbie?

Jim

A spray booth is just a tin box. Put into simple terms, it has two back walls. The inner back wall is just a grid of filters with a dead space of about two feet between the sealed back wall. The fan can go in the ceiling of the dead space or in the back wall. An 8x10 space gives you about an 8x8 or 10x6 booth. The axial tube fans are just as expensive as explosion proof fans. The issue with axial fans is you need the power to run them, the big ones used in most booths are 3 phase. If your booth is in a dusty space you may want to look at tacky filters for the door grid. Id use tacky filters anyways just so you dont have dust falling off the doors when you open and close them. Your door grid should be the same size as your back inner wall or close to it. The two left and right walls should be smooth, can even be drywall painted with latex paint. All you want to do is make a smooth surface so the overspray has les chance of sticking. All your lighting should be explosion proof behind tempered glass. All wires are supposed to be in conduit with the switches on the outside of the booth. Legally you have to have a air supply solenoid that cuts off the air supply to your gun if the fans are not running. You should also install a manometer. You will need this to know when your filters are plugging, as far as I know this is also required by law but really is a neccessity. Dwyer makes some very affordable manometers.

Don

Share this post


Link to post
Share on other sites

This is essentially what you are trying to build on the back of your room. This is just an exhaust chamber that is used to retrofit a small room for spraying.

exhaust-chamber_cat-01.jpg

Share this post


Link to post
Share on other sites

Wow, thanks for all the great advice. Turns out the spray room design is MUCH more complicated than I imagined so this is a real eye opener for me. Clearly I need to spend some considerable time thinking this out but thanks for all the good info that will help me get started!

Jim

Share this post


Link to post
Share on other sites

I'd recommend a positive pressure room, the fan blows clean air into the room through filters, and then out through filters on the other side. This doesn't require explosive proof fans, as the only thing the fan is blowing is clan air.

Share this post


Link to post
Share on other sites

Positive pressure booth's still need a explosion proof fan. They use two fans one is the exhaust and there is an AMU air make up unit. They also need temperature regulation of the AMU to prevent moisture contamination and pressure contamination. Excess pressure causes contamination issues to do flow imbalance. You still need a negetive pressure to create a vacuum at the exhaust.

Don

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now



  • Popular Now

  • Topics

  • Posts

    • Harbor Freight DC to cyclone
      How big is the drum? My guess is you'll want to line it with a contractor bag and weigh the bag down. I've emptied my 55-gallon fiber barrel 3 times and each time it was a complete cluster-F@#, so this time I did the bag inside. So far so good.
    • What's the fastest way to cut a whole bunch of half lap joints?
      I just did this on about 20 or so last night. Took me about an hour to dial it in because I had to find half of 1 3/8" Then i just mowed through them. Much much better quality cut & squareness than I had from my router jig that I built for doing the same thing.
    • Ls;Akfhsdlfhs
      When I started I was guilty of thinking (not voicing) some of those thoughts. Especially upon getting a closer look into the shops of a lot of you here. I know that I make a great salary, and couldn't outfit myself to be like Eric's shop. But then.. two pieces of logic fall into place: 1. He's been doing this for years. He didn't buy it all in one year. 2. He probably has little or no debt, or at the very least, is more financially responsible than me. So those thoughts went away with that realization. Nobody is responsible for my idiocy but me, and that's why I can't drop $30k on a shop in my first year (but 15k is apparently doable with side jobs.) On Youtube, it's a different story. Some of those people get some views and suddenly their entire "cheap" shop is outfitted with gear from their sponsors. I personally don't like that. A big reason is I despise advertising in any form, and another is people shouldn't get free stuff for the sole reason of trying to make me, the consumer, spend more money. It's not as bad as Hollywood people who get $150,000 cars for free to be seen driving them when they could buy a fleet of them, but it's stupid to me. But that also gets me towards this culture of celebrity worship that I hate and how apparently online woodworkers are slowly becoming part of that - and it's a rant so I will skip it. I do think there is a lot of bad content out there, subpar even for my skillset. The reason I've never made anything that looks amazing is because I reach so far above my head that someone should be slapping me down. So I skipped the Ana White thing completely. I skipped that Steve Ramsey guy as well because nothing he makes is of interest to me. I tried to skip April Wilkerson, but unfortunately some of the things she does are exactly the sort of thing my wife will want - and she's really a very good example of someone just trying to better themselves through trial and error. However, to me she is also a very good example of "my shop is now 100% Triton overnight."     I agree completely on Jay. Jay was in that crowd where I ignored most of his projects. I liked his jigs and the way he came up with ways to do things like his bar clamping vises, etc. The guy has talent and a real gift for editing videos, but he wasn't making what I wanted to see (except for shop organization.) But now I'm seeing him make his journey down the path to what I do want to do and this interests me. I still think anything done in pine looks horrible, but I learned something new watching him do hand cut dovetails, so there is value there. He definitely has gotten the motivation to expand his skillset and I like watching that so he's become one of my must watch guys for the week along with Cremona and Marc.
    • Ls;Akfhsdlfhs
      Exactly. Not knocking the guy at all. I used to watch him because he's kind of funny. I stopped watching him after the 5th or so video where he chose a landscaping stakes instead of the material he said he wanted because he saved five bucks. It's one thing to make "budget" builds, but this just rubbed me the wrong way. And I think a lot of these comments have something to do with guys like Ramsey. Talking to a few people last night...  I'm not saying there is anything wrong with saying "nice tool", or something like that. Thats cool, and always welcome. If it weren't for those comments, we wouldn't be posting tools pics or shop tours.  
    • Mothers day box
      Haha! Thanks Lester, you're hilarious !! Sent from my SM-N910W8 using Tapatalk Well she knows im up to something in there. She probably has an idea that im making her a box because last year I gave her her gift in a box also. Lol but yes, it's supposed to be a surprise. Although three of my children saw me making it yesterday so you know how that goes ! Sent from my SM-N910W8 using Tapatalk Well if that happens I guess I'll need another vasectomy! ! Hahahaha!!!! Sent from my SM-N910W8 using Tapatalk
  • Popular Contributors

  • Who's Chatting

    There are no users currently in the chat room