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OK, I'm on my first build and I'm just about to the finishing stage, which I'll admit has always scared the crap out of me. I'm not set up or experienced with this at all. I've done some reading, but it's all still a big mystery to me. I need to set up a spray booth/area of some sort. I'm planning on spraying nitrocellulose lacquer. I've got a good compressor, but really nothing else. My big issue is space. If possible, I'd like to set something up that can be taken down.

I know these are pretty basic questions, but that's kinda where I'm at - just starting out. Any suggestions or a nudge in the right direction?

Thanks.

Later I'll put up a pic or two of the guitar as it sits now.

_________________
"Real guitars are for old people, Mr. Marsh."

Eric Cartman

Hey Mark - Stew Mac has a great book by Dan E. on finishing. It was one of my first reads on the subject and a pretty good one.

Finishing guitars well is difficult, expensive, has some dangers (nitro can be explosive....), and more than one OLF member has recognized that finishing well is..... not.... easy.

My suggestion is to read an overview on the topic, the book I suggested would work, and then narrow your questions down a bit and I am sure lots of folks will be happy to lend a hand.

Bill, IMO, of all the finishes out there (I've not tried all but many)... nitro is the most forgiving. Don't be intimidated in the least. Just do it and learn.

Thanks, Hesh. Sorry, my questions were a little broad.

I've got the StewMac book and I've read through some of it. It's been a big help in demystifying a lot of this.

My dilemma at the moment has more to do with setting up and equipping a spot. I'd love some input as to how to do this with limited space, and preferably something that could be moved or collapsed. I kinda know what I want to do as far as filler, sealer, etc., but I'm sure I'll have plenty more questions as time goes by. My first build is turning out pretty nice and I don't want to screw it up at this late stage.

Thanks,
Mark

_________________
"Real guitars are for old people, Mr. Marsh."

Eric Cartman

Listen, Mark - I started out in a dirt floor barn refinishing a Gibson guitar - in white pearl, no less. All my painting skills up to that time had been doing model cars with rattle cans (and I did a darn good job). I had a Sharpe touch-up gun and a Craftsman compressor and had no idea how to mix lacquer - didn't even know how to set the pressure regulator. By the time I shot the last washcoat - I had it down. Not a fantastic pro, but I learned the basics of competent spray finishing.

You want some tips? Get the best filtered mask you can buy - with carbon filters. Keep the area clean, if you raise any dust walking around - sprinkle or spray a bit of water to settle it. Have a place to mix your fluids and stack your supplies. Have a place to hang your guns - maybe make a simple frame to go around your compressor and cover it with cheap furnace filters to keep it clean (and the oil it emits down). Furnace filters work great to keep your incoming air clean. Get an exhaust fan (explosion proof is good), and filter your outgoing air. Install lots of lights behind you to see the reflections in the finish so you can see your spray pattern, and what the finish is doing (runs, dry spots, etc.). Buy a bunny suit to keep the stuff on you out of the finish if you live somewhere cold or wet. I basically sprayed in a pair of gym shorts and a ballcap because hair and fuzz from my clothes got in the finish. My last real booth was a room about 150 square feet, divided by a plastic wall - the mixing and cleaning area, and my Binks booth. Lately, I've done very good work on the back porch when the wind is low and humidity down.

Just get out there and learn by doing. Make some mistakes, learn from them, you'll get better fast - trust me. Good luck!

_________________
"Act your age, not your shoe size" - Prince

Dan Erlewine had posted a video showing a fold away spray booth. I tried to find it and couldn't. Apparently there was some improvements and he took the "old" one down. He'll post a new video with the improvements "soon". Too bad he took the old one down. There is a video from 2012 showing him spraying in front of a fan mounted in the wall. I doubt this is what you're after, but it might give you some ideas. http://www.stewmac.com/How-To/Trade_Sec ... _shop.html

Got it and understand. There have been threads here in the past on fold away spray booths IIRC just be sure that they are for nitro since explosion proof fans, lighting, etc. are a good idea with nitro.

I've done nitro in a garage with cheap drop cloths (plastic) hanging from the ceiling and no ventilation. Be sure to use a respirator and picking a time of day with minimal humidity which can cause problems and minimal bugs.... is advisable.

I've also both built and finished guitars in a spare bathroom without explosion proof fan and it was a stupid thing for me to have done in hindsight.... Not recommended.

I agree with Glen H. that nitro is the most forgiving but still has a learning curve.

Just did a search on "fold away spray booth" and this is one of the threads that came up, there are lots more is you search on this search key too: http://luthiersforum.com/forum/viewtopic.php?f=10101&t=48671&hilit=fold+away+spray+booth

Mark, I had a similar dilemma and made a simple spray "booth" out of an old guitar shipping box. I simply cut it open like I was going to send it to recycling, bent the two sides at roughly right angles to the back. put a piece of PVC pipe between the sides to hang the guitar from and - bingo! When I want to spray nitro I open the door of my garage, set this thing next to the door so I have good ventilation and shoot away. It is some distance from any electrical equipment so I don't worry (much) about sparks. When I am done I take it down, fold it up and put it away in storage



However lately when I wanted to finish an electric, particularly if I want some sort of 'burst or faded finish, I do it with the guitar flat. I like to be able to walk around it while spraying so I put a couple of blocks of wood in the two pickup cavities to hold it off of whatever I've set it on - here I am using a little step ladder. I can put this outside the door of my garage when shooting nitro (in this picture I'm using a water based finish so I can do that in the garage/shop.



This guitar is outside sitting on a little childs folding table that is fairly low so I can walk around it.



I've finished over 20 instruments now using either nitro or water born finish - they both have advantages. With nitro I make sure the ventilation is good, wear a full on canister respirator (with water born just a dust mask). I have an 8 gallon compressor that I picked up at a yard sale, a water trap and filter, and pressure regulator at the gun. I started with a syphon gun but switched to a small gravity feed HVLP gun which I disassemble and clean every time I use it. My finishes aren't perfect but I'm pretty satisfied - preparation is the key.

You see, Mark? You're a clever guy - you work on guitars. Just furrow your brow for a minute or two, and you'll come up with something that works!

_________________
"Act your age, not your shoe size" - Prince

I had the same need. I nailed some 1 x 2 to the sheet rock ceiling and taped plastic to it making a 10' x 10' area and put plastic on the floor.
Wore a full face and sprayed ReRanch rattles and when finished trashed the plastic. It was cheap, easy and I learned the answer to the question I had.

Cheap plastic room...I guess I watched Dexter to much...but it worked.

Hi Mark,

Not many of us can afford the luxury of space dedicated to a full-time spray booth. I tackled the stowaway booth 10 years ago when I was living in New Zealand. Since then it's lived at various addresses on 3 continents and still does the job.

I've sprayed polyester and nitro, both highly toxic, flammable and explosive, so the first (and most expensive) component was a flameproof, explosion-proof 400 mm (16") fan. Mine is currently built into the opening of a window in our garage, such that the insulated lite can be replaced when not in use (i.e., winter).

There are 4 panels made from 6 mm MDF and lightly framed with 50x50 mm Radiata pine (remember, this was constructed in NZ). The side panels are attached to the back panel with door hinges, so they swing as required and easily detach by popping the pins. I got the idea of a Venturi baffle from a ventilation engineer. The top panel just sits there, but has a rotating hook for hanging guitars and parts. All of the panels can lift away and stack flat along a wall, but we still use the garage for the car and all the garden stuff, even if the booth is installed.

My compressor is in the corner to the left, with plumbing also into the shop next door. When the fan is on, I generally open the outside man door diagonally opposite. I've never missed not having filtration on the supply air, and never understood why folks put filters in the exhaust stream.






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So I wouldn't get overspray on the neighbor's vehicles.....
If you live out in the countryside, maybe that's not a problem for you.

My Binks booth came with filter ready baffles, so I used filters....
Some folks in the US get upset about polluting the air, you know.

_________________
"Act your age, not your shoe size" - Prince

Filters take out the particulates not the vapors. Which is more harmful?

AGAIN - the neighbors don't care for overspray on their cars.
And most folks complain about pollution they can SEE.

_________________
"Act your age, not your shoe size" - Prince

Good point. In our previous shop the weeds would grow up in front of the exhaust fan and get coated in white dust from lacquer over spray. I thought it would eventually kill them but it seemed to have no effect at all.

Geez, thanks guys! This is a lot to go on. When I was doing searches, I was looking for "portable" and "temporary" spray booths to very little avail. This is all a big help.

And I'll probably filter the stuff going out, just cuz it seems like a good thing to do.

_________________
"Real guitars are for old people, Mr. Marsh."

Eric Cartman

Exhaust filtration on commercial booths is intended to keep flammable particulates from coating the exhaust ductwork and creating a fire hazard. The crosslinked particles themselves are relatively inert, unlike the highly toxic VOCs in the solvents. Exhaust filters do essentially nothing to reduce pollution from VOCs that will pass straight through them.

Yes, exhaust filters will keep overspray particles off your neighbour's car. I have no close neighbours and no ductwork in my knock-down system.

Of course, the most important filtration is what you put on your own face -- make sure it fits well and the canisters are rated for volatile organic compounds. The activated charcoal in these filters has a limited life once the packaging is open. Keep them in a sealed ziplock when not in use, and as soon as you smell anything through the filters, change them!

]
Overspray can eventually build up on fan blades, cause balance issues, and be a real pain in the @ss to get off.




Most Weeds have no liver or nervous system.

Most.

_________________
"Real guitars are for old people, Mr. Marsh."

Eric Cartman

I thought weed DID affect your nervous system... Wait, how did we get to this? Oh, yeah. Inhaling VOC's. Yeah, definitely use a filter!

Here's a couple of shots of my temporary shooting booth. I have 2 cheap Harbor Freight tarps clamped to the floor joists for the second story. There is adequate overlap on the one side to keep overspray contained. The one thing I neglected to cover adequately was the floor. And 2K doesn't come off peel and stick with lacquer thinner...

I will repeat, get a good respirator with appropriate filters.

My experience spraying is still beginner, but with nitro I've had good luck just outside. I have no garage and the shop is in the basement. That stuff will stink up the house, I assume not in the healthiest way. I hang it outside the garden shed for spraying and hang it in the shed for drying. Next time I'll try one of those collapsible canopies to keep it out of the sun.

_________________
Mike Lindstrom

Yes, a good respirator is a necessity. I may have mislead with the pic showing the clamping. My shop is separate from the house and has a loft, hence the "floor joists for the second story". Definitely don't shoot in the house...

Even shooting in your separate shop, you still need forced ventilation to clear the highly explosive vapours accumulating in your "booth".

Spraying outside (with a respirator) is actually a pretty good option. On sunny days, you generally have excellent, safe light (no sparks) and good ventilation even without an expensive fan. I sprayed several times last year on my back deck before I got my fan set up again for my foldaway booth. Of course, you have no control over the weather, and this summer that would limit my spray days.