Official Luthiers Forum!

What is your favorite finish for your guitars and why? For my first guitar what would be the best choice for getting a nice looking durable finish? I have experience painting cars and the spray guns (not HVLP though) but I don't have a booth to paint in. I think I like the idea of French polish but I'm not sure how durable it is or how difficult it is to do a nice job.
Thanks
Mike

I have not a lot of experience with finishing. I have more builds in progress that I have finished, but I can speak from my little experience.

First, I don't have a spray booth, and don't have the place and the right to have one. (I'm renting an appartment in a big urban city.) So, I'm going with hand applied finishes, and I really like it. You really put your hands on the work, and you can feel what you're doing. As I don't build tons of guitars, I don't mind to pass many hours on the finish.

For solid bodies, I like polymerized tung oil. Easy to apply, easy to create a nice finish. You can bring it to a nice gloss, and if you want it more glossy, few coats of shellac do the job.

For acoustics, it's definitly frensh polish shellac!

Francis

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Francis Richer, Montréal
Les Guitares F&M Guitars

Hi Mike. My favorite finish for an acoustic is nitro lacquer.
Feels good, and is very clear. I don't use it, because it is poisonous as heck, and I'm not set up to spray it.
Ktm waterbased "lacquers,( what?)", are good, but just not the same.
My favorite for electrics?, oil based poly-urethane, tough as heck.
I'm just now getting into oil based varnishes for acoustics.
Nice yellow look that I like.
Seems to really penetrate the wood,
but, more waiting time beween coats.

French polish all the way for me! But only if Everclear is available in your area, as a lot of the reason I like it is being able to work on it indoors with windows closed and getting it all over my hands without worrying about poisoning myself. Seems plenty durable for my taste. I've heard about water damaging it, but it doesn't bother mine a bit (even near-boiling). Doesn't protect the wood from dings at all, but I'd rather have a dent than chipped lacquer anyway.

I need to try tru-oil sometime too though. Looks like easy, safe and good looking finish with less arm burning than FP.

Also need to try LMI's micro-bead pore filler if I can't get pumice to go easier next time. I'd like to hear favorite pore fillers as well

KTM-9 over Zpoxy. The Zpoxy makes the wood come alive and the KTM is good enough without being an poison/explosion risk...

viewtopic.php?f=10101&t=27504&p=369192#p369192

Mikey

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The Biggest Little City, Nevada
www.hammondguitars.com
I love building guitars!

French polish - It's not poisonous. It doesn't blow up your house. It doesn't require expensive equipment. You can do it watching a movie (or several) in the living room. It's beautiful. Some say it's the best sounding finish. It's easy once you've learned it. There are lots of online resources including a decent tutorial in the OLF archive, but obviously it is easier to learn if you can find someone to show you in real life.

However, if durability is an issue for you, FP may not be tough enough.

A lot of folks have good luck with varnishes. I'm just getting ready to try my first.

And happy new year.

Mike

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Mike Lindstrom

A while ago I decided to make a list of the pros and cons of each finish. Ultimately it comes down to who the guitar is for and what equipment and skill you have . Here is what I came up with:


Any finish properly applied in the .003 to .005 inch range will give good results acoustically. So you have to weigh the other advantages and disadvantages and decide what is most important to you.

Nitro
Pro- buffs beautifully, repairable, forgiving to poor application thickness, ages nicely, a look that's accepted by most consumers
Con-long time outgassing odor, long wait time before buffing, allergic reactions for some builders, reacts to body chemistry of some players, not as durable as some finishes, can craze, cost of application and buffing equipment

French Polish
Pro- beautiful sheen, easy to repair, low cost, no expensive equipment, forgiving to poor application thickness, ages beautifully, not acceptable to many consumers
Con- not very durable, reacts to body chemistry of some players, not as shiny, more skill required for application, shrinks into pores over time

Tru-oil
Pro- steel wool buffs to a natural sheen, easy to repair, low cost, no expensive equipment, hard to get it too thick, ages beautifully
Con-not very durable, not as shiny, difficulty curing over some woods and pore fillers, long wait time if buffing, sands through easily, need a seal coat for even appearance on softwoods, not a look or durability that most consumers want, not clear

Water Based Finish
Pro- no expensive equipment, soap and water cleanup, no explosive fumes, shorter outgassing
Con- not as durable as some, harder to repair, can show witness lines, long wait time before buffing, lower sheen, can give a blue cast to dark woods, not acoustically forgiving to thick application, high cost of buffing equipment

Short Oil Varnish
Pro- no expensive equipment, aged look, ages nicely, low cost material
Con-not acoustically forgiving for thick application, harder to apply even coats, not as durable as some, harder to buff, easier to sand through, can show witness lines, longer drying time, longer curing time, lower sheen, harder to repair, long outgassing, high cost of buffing epuipment

Catalyzed Urethane
Pro-fast dry, fast cure, acceptable look for most consumers, resists chemicals and body chemistry, easy for consumer to maintain, water clear, short outgassing period
Con-harder to buff, expensive material and spray/buffing equipment, not acoustically forgiving to poor application thickness, highly toxic fumes, can shrink into some pore fills

Polyester
Pro-fast dry, fast cure, acceptable look for most consumers, resists chemicals and body chemistry, easy for consumer to maintain, water clear, short outgassing period, no shrinkage, some can be both pore filler and finish in one, can be UV cured
Con-harder to buff, expensive material and spray/buffing equipment, not acoustically forgiving to poor application thickness, highly toxic fumes.

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

I do like nitro lacquer for guitars as it is durable and results in a "vintage look", but it is deadly. I have the proper spray equipment, but still am highly sensitive to it. My major problem with it is offgassing for weeks after unplugging the soundhole.
I don't like many of the cat-finishes as they look like glass and stay that way.
If you think FP is not bad for your health, I knew an old furniture restorer that had lost half his marbles from FP'ing repairs for many years. He was amazing to watch though...

My favorite finish is short oil varnish. It's as acoustically transparent as any finish, and it's more resistant to solvents, skin chemistry, bug spray, ect than nitro. Properly applied it doesn't crack or craze and it looks great. I've made a 2 DVD set on applying an oil varnish finish on a guitar. Varnish isn't super hard, but it's tough. It will dent a little more easily, but it's alot harder to actually chip. The solvent/ alcohol, water, chemical resistance of varnish is similar to catalyzed urethane, but not quite as resistant to these things as polyester.

I've sucessfully applied pretty much every popular finish. Nitro is the easiest to get good results, if you're set up for flammable and hazardous stuff. Polyester, as well as catalyzed urethane carry their own hazards, and each require a learning curve. Polyester basically doesn't shrink so is really easy to get WAY TOO thick. My first polyester finish was .012" thick, and I thought I was applying a thin finish. IMHO both polyester, and catalyzed urethane are better suited for a production envoriment, than finishing 1 guitar at a time.

I've never understood the attraction to waterbased finishes. They're not really water "based", they're water "borne". The finishing material isn't disolved in water, it's suspended in water. That's why they look milky. I suspect that alot of the problems experienced are caused because the....solution isn't mixed good enough, either when being manufacturered, or by the end user. What I'm trying to say is in a less than perfect world one gun full (Or container full) has more acrylic resin and less dipropylene glycol monomethyl ether than the next. From an enviromental standpoint, they're low or no VOC's but alot of people wash their brushes and guns either in a sink and let the finish go down the drain, or outside with a hose and let the waste out on the ground. I suspect the left over finish, and stuff from clean up rarely get's disposed of properly(even though I'm sure the manufacturers intend for this stuff to be properly disposed of). All of the waterborne finishes I know of come in plastic containers, that stay in landfills.....forever. Petroleum is used to make these plastic containers. I suspect that the overall enviromental impact of waterborne finishes really isn't much different than most other finishes. They aren't explosive, or flammable, but the health rating on the MSDS is usually either a "2" or "3", same as most solvent based finishes.

Tru-oil? I'm not a fan. I suppose it isn't a terrible finish, but it isn't hard (like Nitro) to resist dents, and it isn't really tough (like "real" varnish, cat urethane or polyester) to resist chips. To me it's kinda the worst of both worlds. I'll guarantee that anyone who uses Tru oil would get a better finish with Waterlox. The same application methods would work, with more time between coats. The MSDS health and flammability ratings are similar for both finishes.



Added: When I was a teen ager (~30 years ago) I done some french polishing, and my arm is still sore. LOL


Added, again: There's some really great guitars with all kinds of finish. I don't mean to imply that there's one perfect finish, or one inferior finish. This thread asked "What is your favorite finish" and I explained mine, and why it's my favorite. Most of my finish opinions are based on real world experience, but different people experience different things.

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

I can't say I am a fan of some of the modern catalyzed finishes . Some just make it look like wood wrapped in plastic . I am a fan of Nitro as it is repairable and has a low acoustic foot print . The key is to find what works for you . I do like to finish but I am at the point that I do farm things out . Finishing is a difficult process to master and does take time and skill to master and takes some special equipment .
French polish is a simple process and can be mastered without the special equipment of spray finished . As I was learning ,. many of my early opinion have changed . You need good buffing equipment and don't forget lighting . So with this advice I say , find the technique that works for you . Once you nail a finish and you can be repeatable in the process don't change unless you can be proved there is something better .
Often technique is as or more important than the product being used .

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

My favorite is French Polish. I think it looks the best, I like the relatively low tech working environment (in front of a movie on the TV), and I think it does become more durable over time than some people give it credit for. (I haven't built a steel string guitar in a while, though, and probably wouldn't use it there, except on my own.)

Haans, I'm curious about your comment on perceived dangers of FP. Clearly, direct absorption of the alcohol is a risk, but I've never noticed a buzz during the process. I also don't go near denatured alcohol, which could be another side of the risk factor?
Just curious what you were referring to.

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Jim Kirby
kirby@udel.edu

It'd be my guess that, that problem could occur using denatured alcohol over many years. I too use grain alcohol, and wear rubber gloves, as much to protect the finish from my nails as to protect my skin from absorption.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I like French polish the best for my acoustics and Nitro for my electrics. They both are easy to repair and have a great footprint for sound. And i like the way they both feel and look as well. I also like the fact that i can French polish in the house in the winter, that's hard to do with anything else. I have never had a bug get into any French Polish job either.

I finished two guitars in a very expensive short amber varnish. Amber is the hardest natural resin. Long story. You definitely need an UV booth. Lots of very thin layers. Thick layers dry very very slowly. Sags are very dangerous. They never dry properly and you can get some horrible surprises when leveling between coats. Perfect pore filling is CRITICAL. Extremely easy to sand through, guess how I know.
Very easy to be buffed. It gets a mirror like wet gloss quite fast using mere rottenstone. I can't reach this sort of gloss with shellac. Self healing. Mark it and the bump can disappear by itself after a few days. Pretty good impact and abrasion resistance. It still gets cloth imprint after 2 months following buffing after several hours of playing. It is supposed to resist sweat thought, that's why I started messing with it. I can't comment on this yet, let see how it looks in half a year. I know how this guy makes a FP guitar look in half a year: like it was blow-torched.

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Build log

I've used several different brands, but what works for me is Sherwin Williams Fast Dry Oil Varnish. The finished product is pretty much the same with any short oil varnish. It dries and cures quickly(for a varnish) so dust isn't as much of a problem as it is with slower drying varnishes. I used Epifanes for several guitars, but didn't like the slower drying time. Laurent Brondel uses Epifanes, but adds more accelerator than I ever added. Sherwin Williams, (as well as Epifanes) is also almost perfectly clear. For me that's a plus because it gives me control over the final tint, instead of being stuck with a fairly dark amber. Another plus is I can buy it locally. Pratt and Lambert #38 is a comparable product. It may be the same product since Sherwin Williams bought Pratt and Lambert a while back.

I believe most Violin Varnishes are more of a penetrating finish, using more oils, and less resins. I've been told part of it's purpose is to calm the squeak some. If a Violin builder says I'm wrong about that, believe them. I'm not an expert on anything, especially Violins.

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

The one I used doesn't seem to be soaking in much judging from the raw spruce test pieces I did. Plus that is is normal to coat the instrument in all sort of grounds including protein or shellac which pretty much seal the grain. Especially the soundboard shows a good deal of endgrain. If much would be soaked, it would look stained in those areas.

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Build log

I'm in no position to recommend what finish is "best" but I'll throw out another water based option. KTM makes a water based spar varnish (SV). It's an oil modified, self cross-linking urethane. Supposedly, it can be applied with a brush but likely spraying gives better results (which is probably true of most any finish that can be applied either way including other water based finishes). It doesn't have an acrylic base like the water based lacquers so you don't have to worry about the blueish cast that sometimes appears on darker woods when a water based lacquer is used. It also is a little harder than water based lacquer so may provide a little more protection. You can spray all coats in a couple of days and buff a week later which is nice compared to nitro lacquer where you wait roughly a month after spraying to buff. It's very clear and buffs to a nice gloss. It's likely inert to sweat etc. and some say it has a good feel on the neck.

Cons? It isn't as repairable as lacquer (water based or nitro). Not a big issue for me as I think dents, dings etc. add character and don't bother me........but for customers, that may not be the case. There are ways to repair it........and the worst case is you may have to sand and respray a whole area (like the whole soundboard, etc.). Also, you must seal oily woods so the oils don't come in contact with SV or it may not cure properly. As for "not acoustically forgiving to thick application", that is true of any finish. Seems this can be controlled by your spray technique.

Anyhow, thought I would throw another water based option out there that has different properties. Woodys option is appealing. I bought his DVDs and learned a lot from them.

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Formerly known as Adaboy.......

Ken,
You listed "not as shiny" as a con. ??????
L.

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Cut to size.....Beat to fit.....Paint to match.

Oh yeah, I forgot about that amazing feature of being fuzz/dust-proof And I agree with Link, the shininess of a good French polish is just about perfect, and especially neat that it's created simply by varying the speed/pressure/moisture level of the pad. It is shiny, but has a warmth to it compared to the plastic shell look of most buffed out finishes. Screams "touch me", rather than "don't get your oily fingerprints on me".

I also agree with Waddy about the guy Haans mentioned, that most likely he was using/had used a lot of denatured alcohol. I can't imagine my setup causing significant brain damage over time. The shellac and walnut oil are edible, and alcohol is mildly poisonous but obviously consumed regularly in much larger quantities by many people. I never felt any effects of it, and the smell wasn't thick in the air or anything. I do wear the fingers of a rubber glove on my right hand that's in constant contact with the moist pad (hate the clammy feeling of a full glove), but I get a fair amount on my left hand from massaging the pad and feeling the moisture.

Pumice powder is the only inedible part of it... and surely it would be bad to inhale if it gets fluffed into the air, but still no brain damage.

I'm still not sure which way I am going to go but I am now a lot better educated on the subject. I'm probably going to do the French Polish. Thank you all for all the information.
Mike

Link, for those who want a shiny finish, the beautiful sheen of a a good french polish finish would be a con.

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

Well said my friend.
L.

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Cut to size.....Beat to fit.....Paint to match.

I've been to medford a few times, I am surprised you can't just step out the back door and shoot some shine. Anyway, french polish is a whole thing of it's own. Very wholesome. It fits in well with a certain approach to building.

Yup, that's about the gist of it. Your skin, and eyeballs absorb as well as your throat, nose and lungs, whether it's denatured or grain. Doesn't seem like much to worry about till you get old and have done it for years and years. It's then you wish you had taken the precautions. I really don't know of any finish that is not toxic in some degree.

We do have good weather here most of the time but it has been rainy most of the week, now it is clear and 26 degrees and I think we are supposed to get up to 40 today. A little cool for spraying.
Mike