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I've been thinking about my finishes. I like french polishing, and I've gotten decent, finishes from Tru-oil. I've been following the discussion on brush on varnishes, and know some people here do beautiful finishes with them.

So, then, why do people spray lacquer? What makes it worth the expense and the risk? Does it have real benefits to a guitar, or is it just customer demand? There are many products that don't smell like cancer or liver damage and don't explode, so why?

Maybe I just want to buy some new tools. I have found myself wanting a sprayer. Help me justify it?

Mike

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Mike Lindstrom

Good question. I wonder the same thing myself.. The only real advantage of lacquer, in my opinion, is dry time between coats.. That is really it..
I think that the modern nitro lacquer started being used when instruments started being made in large production, and it worked well for efficiency, and made it an easy to repair finish for warranty issues..
For custom/hand builders, the horrible fumes, damage to the environment, fussiness of the finish, extra equipment, etc.. are just not worth the hassle (just my opinion).

If you want an excuse for buying a sprayer, use this finish (it sprays extremely well) and save yourself the brain damage/nervous twitches associated with lacquer fumes.. And you'll have a beautifully finished instrument to boot. http://www.ebay.com/itm/Guitar-Luthier- ... 5af09f8073

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Guitar Maker and Purveyor of the World's Finest Tonewoods
http://www.aaronhixguitars.com/
http://stores.ebay.com/A-Hix-Tonewood-a ... r-Supplies

That is what I mean that lacquer has the speed advantage when it comes to how quick you can apply successive coats, whereas with the U500 varnish that I use takes 10-12 HOURS between coats.. The advantage with it, though, is that each single coat of U500 builds about the same as 2-3 coats of nitro, and it is completely cured and ready to buff in about a week, as opposed to a month for nitro to fully harden.
I used nitro lacquer for several years, and had great results with it, but I am highly sensitive to chemicals. I would end up with a migraine headache every time I used lacquer, even with a high-end respirator.. I had to switch to something more health-friendly.

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Guitar Maker and Purveyor of the World's Finest Tonewoods
http://www.aaronhixguitars.com/
http://stores.ebay.com/A-Hix-Tonewood-a ... r-Supplies

I've only used nitro from spray cans but now I have a little booth with explosive proof ventilation and I would like to try it on a few guitars. My schedule with water-based lacquer is seal with shellac, 4 coats of WB lacquer, level, then 4 more coats of WB lacquer, and wait 2 weeks before final sand and polish. I can do 4 coats in a day but have to let it dry for 2 hours.

Filippo - it sounds like you're skipping the intermediate level sanding, this would certainly save me some time. Are you just shooting 6 coats over the shellac (or other) sealer?

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Steve Smith
"Music is what feelings sound like"

I can lacquer several guitars in a day. It takes over a week and a half to French polish three.....there are other coatings that make absolutely more sense from a lot of perspectives like conversion varnish and two part urethanes, but they are definitely a tougher sell on a higher end custom guitar.

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Brian

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

https://www.howardguitarsdelaware.com/

I only sand between coats when working with shaders or toners to level them. Other than that i sand the sealer level and then shoot my 5-6 coats of lacquer.

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Brian

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

https://www.howardguitarsdelaware.com/

Aaron - how many coats of the U500 do you use on a typical finish?

I love spraying Em 6000 , I use Em 1000 for the sealer, clean up is as easy as rinsing with clean water , low fumes, although I do use a mask, dries fast and very forgiving.....what more could you ask for???

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MK5acoustics.com

Usually 4-5 coats is all it takes.

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Guitar Maker and Purveyor of the World's Finest Tonewoods
http://www.aaronhixguitars.com/
http://stores.ebay.com/A-Hix-Tonewood-a ... r-Supplies

I've never sprayed any finish. Always seems to be a cheaper and simpler alternative. I can brush on Shellac or a Spirit Varnish in very little actual 'working' time. It's a fraction of the time I spend doing French Polishing. The other advantage is that there is zero clean up required. I suppose you can get the same advantage putting on an Oil varnish with disposable foam brushes.
The simplest finish that I do is on a Vihuela - three wipe on coats of Danish Oil and a bit of wax on top of that! Close to the wood but it's the type of finish that is expected on those Lutey instruments. Some might go for that type of finish on a Classical Guitar but it seems that SS Players want hard and glossy.

Thanks Aaron.

Cleaning up after spraying takes no time. Put some thinner into the gun, spray for a few seconds. Done!

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Doug

Don't let fear or common sense stop you from trying to build something

Brush is quicker. Stop, put brush down. 0.5 seconds

It just requires a different technique, you have to put the color directly on the wood. It is a lot less forgiving than spraying color coats. I've used a cheap airbrush to shoot color directly on the wood, usually mixing the color in very thin shellac, but sometimes just color and alcohol. I've also used the water soluable tints diluted in water, shot directly on the wood. Both have pros and cons.

Now that I think about it, you're right! It is more difficult to do a sunburst with TruOil (or any hand applied finish for that matter).

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A man hears what he wants to hear, and disreguards the rest. Paul Simon

I use nitro because I don't like blue guitars. Not to mention it is so easy and quick to apply. Full burn in. Finish can be thin. Not as "toxic" as some other finishes. And as was mentioned, bugs sand out nicely. Just don't throw matches in it.

I wish I had the room to spray nitro and the chance to get good at it. But I only build 2 or 3 instruments per year so I don't think I'd get much practice at it to be good.
Nitro is a great finish IMO. Tough, clear, resistant to most common solvents, repairable, tint-able, and looks great. The only big down-sides are the fumes, equipment & skill required

Filippo, what is your schedule? I think I remember you saying you spray it in-thinned, too, right? Doing it all in a day would be convenient. I'm used to see three coats a day and letting it gas overnight.

Nitro in spray cans aint worth a hoot: takes forever to harden.
Spraying with a gun is fast, easy and forgiving. Not to mention less worry about dust settling in the finish.
It is pretty nasty stuff though. Behlen Instrument nitro is only $17 a qt. at Grizzly; seems cheap enough to me.
I just got two quarts in today. Reckon I'll be killing some brain cells this weekend.

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wah
Wah-wah-wah-wah
Wah

Ok, toolbox talk time.......don't be lulled into a false sense of security that because these type coatings are low in odor and fumes does not necessarily make them safe when sprayed. While not flammable they do pose quite a health hazard as an aerosol. the cross-linkers and other bits of chemistry it take to pull of a water borne acrylic are not something you want to be putting in your lungs. Quality masks and ventilation are a must .....now back to your regularly scheduled program.

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Brian

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

https://www.howardguitarsdelaware.com/

Good point Brian, I spray in my garage with the garage door open at the botton and the side door open to create good ventalation. plus I use a mask with filters...simple but effective.......

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MK5acoustics.com

Thanks for you thoughts, everyone. I'm surprised there weren't people saying harder, or shinier, or other specific characteristics as it certainly has fans. For me, I'm partly driven by requests from people who want guitars, but mainly I like the idea of the rapid drying. I don't do a good job of keeping stuff out of my finishes as they dry. It also seems like melt together layers is just better if it's an option. And of course, while I get a pretty good looking finish with the things I do now, every day, someone here posts pictures I can't even believe, so I have to keep working at it.

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Mike Lindstrom

It works well, and is easy to use. As for space I use a temporary booth with plastic that I staple to the ceiling and lift out of the way when not in use. A small explosion proof fan and a roll of plastic is all that is requited

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Nitro and shellac can be put on very thin. Their brittleness means that they don't absorb high frequencies. On a guitar you want to preserve all the high frequencies you can. A violin, played with a bow, needs a tough flexible varnish that absorbs the right amount of highs. This is the opposite of a guitar.
When I select woods for a guitar I rap them with my knuckles or snap them with my fingernail while holding them loosely near my ear. Some wood just has a crisper, longer-lasting ring to it than others. Shellac and nitro let this crisp woody quality still be there after finishing. Thick layers of modern cross-linked finishes (epoxy, polyester, urethane, polyurethane, anything that uses a catalyst) definately kill this quality and replace it with a plastic sounding alternative. I suspect that real guitar lovers who use modern finishes know how to apply them as thin as possible. You sure don't want to try to sand that stuff thinner, it is hard as a rock.
French polishing lacquer encourages even thinner finishes, but spray is fast. With clear nitro finishes you can't hardly make a mistake that isn't easy to fix.

Modern conversion coatings as well as most catalyzed finishes have a mill barrier. Application of dry films over 5 mills must be avoided or failure will result. That is not to say they may not have damping qualities, but that its not tied to the coating being thicker.

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Brian

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

https://www.howardguitarsdelaware.com/

I spray varnish, and it takes me an assload of time to do a finish. 36-48 hours drying in between. Sanding every coat in between. 7-9 coats. Yep, my arm is buffed. They do come out looking very nice, and the varnish is not too nasty.

I want to try a nitro finish, simply because of the time factor. Each coat bites into the next, eliminating the need for scuff sanding, and it dries in 15 minutes. sweet! Also, another reason it's appealing is the ability to repair it.

ONLY wet sanding a guitar once then buffing it out sounds like a DREAM.