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So, for the umpteenth time in 40+ years, I'm redoing the spray booth.Because I live in an area with 80% plus average humidity, a Hawaiian rainforest, it takes a few gyrations to tame the lacquer for spraying. Blushing is a constant battle. Now that I'm a little older, it is getting difficult for me to flip guitars around one handed in the spray booth, so I'm going to a barbecue spit style of holder on which I can rotate the bodies, as well as bodies with necks on. Generally I hang and heat up my instruments outside the booth in a closet size enclosure before and after spraying, use enough retarder to combat the elements on a given day, and do reasonably well avoiding blushing. I use infrared bulbs, with a heat shield between the bulbs and the instruments,as a heat source and they work well in an enclosed space. Years ago I tried heating the air going into my spray booth, and that worked sort of, but I eventually went to the heated enclosure. Now I want to go back and revisit the heated air in the booth, because I don't want to have to remove the instruments from the barbi after each coat. No need to warn me about explosions. I'm totally up to speed with explosion proof lights, fan, etc. I would like to fan inject some heated air into the booth through a short tunnel. Lacquer is not going to travel up an airstream, so I'm not too concerned about it reaching the heating element. In the past I've bought a couple of space heaters to experiment with, but their thermostats don't allow them to go much above the average temp in my shop. I've also tried drawing the dry air from my dehumidified workspace, usually at 40-45%, through a wall port into my spray booth. That did not work at all. I need heat. So, what I'm wondering is if some of you cold climate guys have ideas for electric heat sources, my shop is not clean enough for open flamed gas, that don't cost an arm and a leg, and that will heat into the 90's without shutting down. Thanks, Bob

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“ The meaning of life is to find your gift and the purpose of life is to give it away” Pablo Picasso

Bob, have you considered one of these for the spray booth? It's an oil filled radiant heater. For a small area it should be fairly efficient.

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Bill Hodge


One does not simply, own enough guitars!

Bob, although I do not live in a rain forest as you, we do get some humid days in the summer where humidity outside is 80% for weeks. Ever since I switched to an HVLP turbine for spraying I have not had any problems with blush. The turbine heats the air delivered to the spray gun. I have the turbine in my shop so it is pulling air at 40% to 45% RH that is fed to the spray gun. My shop is adjacent to my booth which makes this possible.

Chuck

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Bill, That might be of some use. I'll check it out. I really need instant on and off heat where I can heat an area very quickly, and I'm not sure a radiant heater will do that. Still, I'll have a look. Thanks.
Chuck, I switched to turbines 20 years ago. The heated turbine air is not enough to do much good when the outside air temp is cool and the humidity in the high 80's-90's, which is common around here. I live at higher elevations, so I don't usually have that nice warm Hawaiian beach temp. When I had a shop in town at sea level, up until 15 years ago, the heated turbine air usually did the trick. I have not however, ever tried having the turbine inside my dehumidified workspace so that it drew dry air. My booth shares a common wall with my workspace, and I already have a cutout that I used for my attempt to draw dry air into the booth, so I can jury rig that for a trial tomorrow. That would be very cool if it worked. The only things that work pretty well so far, are heating the body of the instrument higher than air the ambient air temp, and spraying hot lacquer. Both of those are a pain, but they are my go to, get out of jail cards.

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“ The meaning of life is to find your gift and the purpose of life is to give it away” Pablo Picasso

You'll be moving a lot of air with the exhaust fan, which you have to replace, and that's got to come from outside somewhere, even if through your workshop.
You'd have to do the calcs to know how much air you have to heat and to what temperature.
Also I don't know what supply you have to the shop.
As a suggestion something like a 3kw 110v 32 amp Electric Fan Heater (or 2) in your workshop would be a start , but it may be not enough on its own. Dehumidifier in the workshop cranked up to max. possible without icing would also help too.
Draw both your turbine (in the workshop) and spray shop feed air from there, at least it would create a "buffer zone" for the humid air.
Worth a shot?

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I am not sure of the need for heat in a tropical environment. I find it best to simply run a dehumidifier in my booth on the humid days. I need to heat in the winter for temperature. They make heated make up air systems for spray booths. A friend with a body shop just installed a new booth with heated make up air. The systems are not cheap but work very well. The way i see it with any other solution you come up with on your own is heating so much air so quickly. As soon as i kick on my fan I am pulling 3200 CFM of air through the booth and the make up air is coming directly from outside. That is a lot of air to condition for temp and RH at one time.....

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Bob, This might seem like a real silly and obvious suggestion but it seems that it would be a lot easier and cheaper to just switch to urethane or polyester. No blushing, faster dry time and a thorough cure within a day or so and the booth can even stay humid as long as you move the instruments out after you've sprayed.

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jw ( o)===:::

Lots of ideas. Thanks for all the replies. Probably the most obvious useful one is switching finishes. I admit to being envious of my friends who have that one day cure scenario and super glue repairability, but I'm a lacquer person at heart. Wish I could just spray on "good spray days", but I only get a few of those a year so that is not a luxury I have. I'll recycle some of the suggestions and see what I can come up with. Good luck with all your building.-Bob

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“ The meaning of life is to find your gift and the purpose of life is to give it away” Pablo Picasso