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I had a big question and concern. I am exploring options already as to what and how to finish my guitar, i can either outsource it and pay a fee, try to do it myself, or i have a couple of friends that work for the big dealers that do finishes for the likes of (mercedes benz, bmw, etc.) that said that they could do the finish for me, granted its clear. Will a car finish work on a guitar?!.. I can imagine it would but im so confused so i need some advice as to if its a good idea or not?! Car finishes are extra strong to withstand the weather, sun, etc, so i dont know if that would be a something that would affect a guitar! .. Any advice would be appreciated!

Jonathan

Car finish would work on an electric guitar, in fact most Fender colors are car colors.

For acoustics you have to watch out for finish thickness, too thick a finish and it will dampen the sound of your guitar, not to mention make it harder to repair it. So whoever you outsource it to make sure they don't coat it in 1/8" of plastic.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

How thick should the guitar finish be!?

ideally no thicker than .005", about the thickness of a sheet of paper. The thinner the better, because additional finish adds weight to the soundboard, changing its sonic characteristic.

On electric guitars it's not as important but people say they can hear the difference.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

There are a lot of finishes used on cars, not all would be great on a guitar. Find out what they spray first then get back to us.

A final thickness on an acoustic guitar should be between 0.004-0.007" give or take

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"There's really no wrong way, as long as the results are what's desired." Charles Fox

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Also, a guitar doesn't need to be weatherproof, because if you expose a guitar to the same environment a car sitting outside would be exposed to, a lot of things are going to break before the finish. Auto finish, on the other hand must withstand years of rain, sun, snow, humidity, or whatever else nature can do to it, so the finish has to be very durable. It must also protect the car body from rusting.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Tai speaks wisely.
A car, is not a guitar.
Learn to do it yourself,
or have a guitar finisher do it.
I repaired a Gibson ES335 where the finish was 1/16" thick.
Fine for an electric,
not an acoustic.
If somebody can hear the difference on an electric with too thick a finish?

Although you must ensure that if you are shooting automotive clear that you watch the film thickness, it's easy to go too thick with them since they don't shrink as they dry like lacquer. However prep work is everything, and with lacquer you need patience if you want professional result.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I heard the original nitrocellulose lacquer finishes were used by Henry Ford on cars, and guitar manufacturers decided to try it too because it dried so fast and hard.

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"Preoccupation with an effect gives it power and enhances the error"
from "Your Owner's Manual" by Burt Hotchkiss.

i had no idea that nitro could weather any water whatsoever, but, from wikipedia:

Some builders use automotive finishes(catalyzed urethane) on acoustics. I'm not sure (beyond what Todd's used on electrics and necks) what brands they use. I suspect some woods would require a sealer to keep the oils in the wood from interfereing with adhesion. I prefer wood finishes. I use either Sherwin Williams Varnish, or Axon Polyester, but again, some really good builders, and finishers use automotive finishes. A typical automotive finish(on an automobile) is 2 mils thick. (.002") As stated earlier, nitrocellouse lacquer was used on autos for years.


Added: Joe White was a very successful automotive painter, before he became a very successful guitar finisher. He doesn't use automotive finishes on guitars even though he has extensive knowledge about automotive finishes.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

And you could get the Model T in any color as long as it was black.

FWIW this is nitrocellouse lacquer, painted in 1988. Nitro was already getting hard to get for autos back then.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

I have to agree with those who recommend only to hire someone is very experienced with acoustic guitars. I learned this the hard way!

Or do it yourself and commit to the 50 - 100 hours it takes to do your first good finish.

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http://www.chassonguitars.com

I use Dupont's Chroma Clear HC-7776S multi-mix snap dry clear coat and it works just fine, a very professional finish in just four coats. You can always test to see how thick your finish is by taping a part of the fretboard extension and measuring a chip from off of the tape.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

I think the issue of automotive finishes for guitars has been very well addressed here. I certainly have nothing to add on that.

I could add a little more about the issue of finish choice for beginning builders. I've been scratching my head about this and reviewing the pro's and con's of all the alternatives. The cost of a first-class spraying set-up is considerable, but you can use a cheap compressor and an off-brand jamb gun (and spend more time sanding), and cobble together a simple folding spray booth. Toxicity of nitrocelluose is an issue, but you can spray outside or use oil-based varnish, much less toxic, or water-based lacquer, even less toxic. Water based can be tricky and there are color and adhesion issues. These issues are always solved by the latest version, you hear when it first comes out.

It is irritating to be told over and over that surface preparation is the most important part of a good finish. It is even more irritating to discover how true that is, and how difficult it can be to prepare a truly good surface for a gloss finish.

Any approach you take will have a learning curve, and will require many hours of work for each guitar. My personal choice, for the moment, is to French polish my first guitars and keep the option open of sending out ones that I want to have a more durable finish. I kind of enjoy French polishing, while setting up and breaking down spray booths and cleaning spray equipment with solvent over and over isn't my idea of a relaxing avocation. YMMV.

Answers to these questions will help guide your choice:

1. How much money do I have to invest in finishing?
2. How much space to I have to devote to it?
3. What kind of wear will my guitars (my first guitars) be subjected to?
4. (If building guitars for sale:) What kind of finish do my customers prefer?
5. (If building guitars for your own satisfaction:) What kind of work gives me satisfaction?

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Tim Allen
"Never hurry, never rest."

While finishing early on is a royal pain in the rear end.... It does have 1 specific advantage... Cost you gotta drop on a Hobby... A can of lacquer or varnish costs about $20.00.... A Pro guitar finish costs $300-$500.... If I got to the point where I was selling regularly - and the $300-$500 cost would bring itself back to me in the sale... then I probably would do it....

At this point... While I royally hate the finishing process.... It really doesn't matter... I don't even have the $300 to drop on a finish.. so it's an easier decision for me...

Since you built the guitar yourself, you should finish it yourself. My recommended approach would be to French polish it.

Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Being able to put a professional looking finish on a guitar that does not impede its sound is actually harder than building the guitar itself. If you can learn to do that, you can do anything.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

What Tim and Pat said.
If I had a spray booth, I'd spray varnish.
I don't like pulling the car out of the garage, messing with the gun,
cleaning the gun, then watching dust get on the finish.
F.P. is the only way to go for me for these reasons,
weather/humidity hasn't been an issue,
it's enjoyable,
you use a lot less sandpaper,
WAY less toxic,
easy set-up,
shellac flakes are cheap,
and mostly,
it is a beatiful finish!
I know it's not as durable,
but it is an instrument,
and most people take good care of them.

I tend to agree......at least for the most part. I don't think anyone should risk their health just to do their own finish. A safe finish might not be acceptable in some circumstances. It takes alot of work, practice, and skill to do a professional grade finish. The same is true for pretty much every aspect of a build. I just routed the binding off of a body I'm working on because the end joints weren't as good as I wanted them to be. There isn't a Joe White of binding, so I'll have to do a better job.

Joe, if you read this, do you do binding jobs?

TruckJohn mentions the cost of sending out a finish. He also mentions how much work it takes to get it right. I've seen one of John's guitars and the finish was excellent. I'm also familiar with his process, and it is alot of work. The only substitute for either the hard work, or the money is a sub standard finish.


Now, it's back to the shop to get an invisable, or at least acceptable joint in Holly binding.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/

Woody, This is probably the single biggest problem I face with finishing guitars. Second would probably be removing the drum sanding lines. The fact that you have faced the reality of re-doing the bindings being the best way to correct gaps (and other binding/purfling issues) shows integrity. I admire that.

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jw ( o)===:::

I just came up with how I THINK I'll do acoustics, for the next few.
F.P. the top,
and use General wipe on poly for the back and sides.
No spray, for now.
I hope they don't outlaw wipe on poly in California,
cuz that's where I live.

Is the General wipe on poly satin or gloss and where can you buy it? I did a search online and found lots of General finishes, but no wipe on poly.

http://www.generalfinishes.com/where-buy
What I have is,
"Seal-A-Cell" clear sealer,
and "Arm-R-Seal" oil and urethane topcoat, gloss.
I pretty sure they make a semi gloss.
I wouldn't use it on some porous woods on an acoustic,
or any acoustic top, but it might be okay.
I did a test on a side cutoff of mahogany,
and it went all the way through the pores on a .095" piece.
Really tough surface.
Good for an electric,
and I think good for less porous wood back and sides.
I bought it at Mt. Storm, a hardwood store in Windsor CA,
which is where I live.
I'm lucky, Mt Storm 10 minutes away,
LMI 7 minutes away,
Allied lutherie 13 minutes away,
yay!!!!!!!!!!!!!!!!