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Just wondering what you guys are using. I do varnish and lacquer hence the need for some type of exhaust system. I just hate the fact that they suck all the warm air out in the winter and all the hot air in in the summer.

I know there are several small hobby-type spray booths that have charcoal filters, etc. and no need to exhaust. Anybody on here ever seen or worked with one? The work area is pretty small but would hold one guitar body.

Otherwise my new spray room will have an explosion proof fan with rheostat speed control exhausted to the outside.

thanks.
Steve

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"We might not be big but we sure are slow"

You are asking for an indoor solution...right? Tough one. I am a regular on the ReRanch forum where a lot of the finish/refinish and restorations folks hang out. This is always a topic over there too. You might want to stop over there and ask too.

I spary lacquer about 9 months a year. I do so out in the garage with plenty of ventalation. Even then, I use proper masks to offset the dangerious fumes. Indoor spray rooms really require excellent ventalation. In one case, I have seen a guy that built a "spray" booth that is free standing (and collapsable). It allows him to stand outside of the booth and spray into it. This first and foremost gets him out of the area that is most densely populated with the toxic fumes. His booth (really a large box on legs) also has a home made down draft system that makes up the floor (or bottom) of the booth. This keeps overspray to a minimum and of course gets rid of a large portion of the fumes as well. As you know, even after your done spraying, the Lacquer continues to gas off toxic fumes...and does so for several days. (actually for well over a month..but it most intense the first day or so). So even the gassing will need to be considered when spraying indoors.

I am not sure how to get around sucking the hot and cold air out of the building though. I would assume a down draft ventalation system would be a low velosity set up. It would not take a lot of cubic air of movement to pull the fumes downward..as that is the direction they want to fall anyway. So maybe a low volume air handler would be the ticket in that small of a setup.

Let us know if you come up with any solutions.

Thanks,
Joe

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Joe

I suggest if have the room in the shop, you build a dedicated room with exhaust fan and cross ventilation. At the shop this is what Bill has. It has an exterior door to enter, and heavy plate glass (industrial) to see into. The exhust fan goes out of a window (this is a basement shop building 30+ guitars a year) so not see it. You can stand in the shop while spraying is going on and not notice it or smell it much at all. You can stand outside and not smell it AT ALL. Bill went to the nieghbors to tell them what he was doing and if they had a problem with fumes to get with him. That was about 5 years ago and all they contacted him about was building or refurbish their guitars. No complaints.

If worried about enviroment, don't spray lacquer or poly or other harmful things or what folks think is harmful to the air, and go with water, or another type of "non toxic" whatever that may be. If want to spray and use lacquer, poly or other things, just do it just do it right. Rule one don't make it wrong and blow up the house/shop, or injure yourself inhaling fumes. Your shop probably won't make the temp go up in the nieghborhood. In other words decide what you want to spray and do it right, whatever your decsion is. Anyway I hate green and love brown.

Although I'm pretty satisfied with waterborne laq. I've often wondered about this too. There are devices called air to air exchangers that exchange / heat /cool inside air with outside air. The rub is that the ones I quickly googled were very low CFM. On the other hand I only googled for about 5 sec. It's also not clear from what I saw whether they 'mixed' the outgoing air with incoming air or whether they used a heat exchanger type setup.

May be worth looking in to though.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

I forgot on the noted knock down rig, that is on the tools and jig page and by Tim McKnight.

One could buy or make one like the Griz unit.

No matter what, if spraying inside, particularly with lacquer and other dangerous stuff, you need exhaust and cross ventilation. If not use these and blow up the shop, insurance probably won't pay. I can gurantee you they will hire someone like me to determine what you were doing and what you had for prevention to see if didn't do it right and not have to pay claim. If that is the case, you won't have to worry about it, but your surviving family members will have a hassle. That is good for someone like me, as I, as most do(if any good at it) charge $75 to $95.00 (I am even higher than that and had more work than wanted) per hour and it would be a couple of days (about 20 hrs.) of work. Make a shelf or hanger to hold work in spray area during the gas off period, which then depends on what you use for finish. If not sure of what to do or want to do, and concerned about enviroment and dangers, call one of the pro finishers. They are set up for all kinds of things. Or lean french polish or other hand methods, but still may want to wear a mask and take personal precautions.

Yeah, there is a version of a "knock down booth" in the jigs area too. The one I have seen is pretty much the same idea, but with a down draft ventalation system built in.

Good luck.
Joe

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Joe

yeah the Grizzly booths pull a bunch of air and would empty a small 12x24 room in about 2 minutes!!!

I'm thinking of using an explosion proof fan with a rheostat control and wired to a 10 minute cyclical timer like we use in poultry houses. That way I could run it slow while spraying and then have it run for a short amount of time (say 30 seconds) every ten minutes, however, I like the idea of the self filtered systems that the hobby companies sell. You can run them continuously for several hours or until the intensity of the "gassing" has dropped to bearable levels without ever taking air in or out. Just not sure if they're large enough.

thanks for the ideas and keep 'em coming.

SR

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"We might not be big but we sure are slow"

Hi Steve,

How many guitars a year do you plan on finishing? If it's not too many, you may consider renting time in an established commercial spray booth at one of the local furniture refinishers, cabinet makers, or automotive refinishing shops in you area. You could do your spraying in a proper booth and set up a small ventilated drying area in your shop.

You may find that you won't have any insurance coverage on your house if you have a spray operation there.

Just a thought!

Call

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Remember, there are no stupid questions, only stupid answers!

I already have commercial coverage on my shop so I think I'm okay other than it will prolly raise my premium.

I hope to get up to 20 or so next year maybe so going back and forth isn't feasible. There is a place here about 8 miles away but I just can't see making it work. I would rather break out the darth vader mask and go to it. The majority of my finishing is varnish which is more user friendly but turpentine aggravates my sinuses. Mineral spirits aren't too bad and shellac is no problem...mainly the nitro.

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"We might not be big but we sure are slow"

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Freeborn Guitars
and home of BeauGuard©

This is pretty much what I had seen being used.

JD

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Joe

Hello!
I built a booth into the corner of my basement, 6'x4', quickly framed with 2x4 and covered with clear poly. For a door I found zippers you could attach to the poly and then cut with a knife. Seen them at Lee Valley, cheaper at the regular hardware store. Beside the door I framed in regular 16x 24 furnace vents, stacked 2 deep and 2 high, for a total of 4, duct-taped all around them to create a seal. Basically the idea was to create an airtight room with the only airflow being through the furnace filters. I spray with KTM-9, so I don't have to worry about fumes, this will ONLY work with waterbase. When I spray, the compressed air adds positive pressure to the booth, forcing the air through the filters to remove the particulate. Of course I am wearing an appropriate respirator in the booth as it is a cloud of overspray till it settles. I've used it for several guitars now and it seems very effective. The trick is to make sure air can only escape through the filters and not any other cracks. I don't even have a fan in there, it took 40$ and 4 hours to make. Hope you find that useful.
Cheers