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I'm currently scraping and sanding the bindings back on build 1 and my mind is turning on how to finish and what to use. For pore filling I intend to use west systems epoxy, where to go from there is less clear. My first thoughts turned to Danish oil, which I've been told to avoid as is doesn't cure hard enough I then though of tru-oil, but now I'm leaning towards French polishing. This isn't to say that lacquers or other finishes are out of the question, I have a compressor and have a little experience in that direction, but I'm far from good at it.

What I'd like to know is the pros and cons of each and why you chose the finish/s you do. I'd also like to know time scales as I'm itching to finish it as soon as possible so I can hear it months away yet as I need to finish carve the neck glue the fingerboard to it etc.

Thanks Guys I'd be interested in your opinions

John

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Formerly JJH

I learn more from my mistakes than my successes

Hi John and thanks for posting this.

Nitro: I finished my first 6 or 7 with Nitro and it was not difficult to do. But..... nitro can be dangerous if one is not set-up to spray it safely. You need an explosion proof fan and nothing that could be exposed to the explosive vapors that creates a flame or possibly a spark can be in the vicinity when you are spraying nitro.

You can spray it outside if you have an agreeable climate and no neighbors or pets in the vicinity.

After spraying and following a finishing schedule (Stew-Mac has a good one available on-line) it's best to wait about a month for the finish to harden before rubbing it out and buffing. And of course a respirator is required and where you place the guitar for he finish to cure needs to be a place where the out-gassing won't create a health hazard for anyone or anything.

BTW I used Stew-Mac's rattle can nitro with good results.

French Polish: If it were up to me all guitar builders would learn how to French polish or at least do one guitar with FP. I only did one.....

As for safety it is far safer and less toxic to use shellac and the only really harmful ingredient is denatured alcohol which can be substituted with 100% grain alcohol which of course can have other uses as well......

There is something beautifully therapeutic about French polishing and I very much enjoyed the process. Michael Payne taught many of us how to FP and so too did Robbie O'Brien with his excellent DVDs. My bro JJ taught me. There is also the Milbourn tutorial available and I think that we have a link to it here on the OLF.

It takes some time but IMHO when you consider all the steps with a nitro finish I don't think that it takes any longer to do than nitro.

FP is safer, cheaper with far fewer things required, puts you in touch with your work at a more intimate level (no jokes please...), and imparts a beautiful and warm glow to the wood.

The down side is that it is not as tough a finish as nitro but it is easily repaired if you have places, like the neck, where it may wear off.

In addition some of us believe that a FPed top is a sonic joy to hear.

As for oil finishes I can't comment so I won't. But Ron Wisdom has built some beautiful guitars with a superb oil finish.

Since you are on your first guitar and if it were me and I could do it all over again I would FP the guitar.

Oh yeah - a True oiled neck is also a very cool thing for the player and easy to do as well and can be combined with a FPed guitar body.

Thanks Hesh your swaying my mind here as I haven't a spray booth and the weather here hasn't got above freezing in the last 2 days and I have neighbours with pets so that's a consideration as I didn't know quite how lacquer was is brushing an option, also I have some Ercalene metal Lacquer which I've brushed onto things I've forged and are to be kept indoors its a xyelene based cellulose lacquer but the plasticiser is for metals not wood and not being a expert I wouldn't know if it could work I guess I could try it on scraps.

I've printed off a copy of the Milburn tutorial and am off to bed with a little light reading Once digested I can make a more educated decision.

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Formerly JJH

I learn more from my mistakes than my successes

Hi John,

You could give some thought to water based lacquer. It is much safer to spray. I used Target Coatings Ultima Spray Lacquer with my HVLP setup on the OMC I built earlier this year. I just sprayed in my garage. First time using it, and I needed about three applications until I got my settings dialed in. Once I did, the finish layed down great. I could shoot three coats a night and level prior to shooting the next night. The finish buffed out very nice, and after 7 months is holding up quite well. Something to consider if you want lacquer but are concerned about the safety.



Ken

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http://www.casperguitar.com

Beautiful guitar....! Thanks for posting..

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http://www.PeakeGuitars.com

I'll second the Target product. Target USL on the body and a Tru-Oil neck is a great combo for a non-commercial builder. USL is very forgiving, you can safely spray it at home without an expensive booth, and it buffs out to a very nice gloss. Most of the problems I've seen with waterbased have been on necks. Gerald Sheppard posted his schedule here a while back and it works well.
Terry

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Thanks Parser. I had no intention of hijacking the thread, but I had such great success with Target's USL, I felt a picture may help illustrate how good the product works. I used the USL on the neck, which turned out steller and shows no wear after almost daily playing. I kept good notes of my setup, which I would be happy to dig out and post if you decide to go this route. The guitar was my first time using water based lacquer. I have some experience spraying, but the USL really is a joy to use as others have attested. With a decent setup, some patience, and a little practice, I think most anyone can have succes with this stuff.

The guitar sounds terrific as well, so no issue with the USL adversely impacting the sound. I'll be spraying all my guitars with this finish going forward.

Ken

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http://www.casperguitar.com

Hi John

I have used Tru Oil on the whole guitar and it works just fine. It is very quick, very easy and a good starting point. Just make sure you Shellac the soundboard first. this is a good option for a first build.

I have used French Polish which is also a great option. It is a technique which needs working at but the results are excellent and you will definately hear the difference in the finished guitar!! However, like the oil finish it is not very robust and will mark easily.

I am currently about to use a product called Rustins 'Plastic Coating'. It sounds foul, I know, but it is easy to apply (with a brush!) and I have heard good things about it. You can get it from Axminster.co.uk.

I am in Basingstoke. Whereabouts are you? If you're near maybe we could meet up and discuss it more.

Oh Yeah, DO NOT RUSH THE FINISH. I was so desperate to complete my first couple of guitars that the fit and finish went out the window. Take your time man.

Mat

Finishing is maybe the hardest part of the build. I personally use only Nitro. This is a terrific finish , as you can go in and repair it at anytime. Water based finishes are ok where you have to consider the environment. I cannot stress enough the importance of getting all the basic finish steps done correctly.
I don't use the epoxy so read and follow their instructions. I would think you would want to stain first. Getting the fill right , and sealing is a key to success. French polish is a very good finish and is a low tech job , but you do need to have a good technique . Again , this is also a good back door finish that will allow repair at a later date.
Urethane , Poly finishes , don't have the repair option lick the old finishes do , but they are an option. Remember you need to fill seal and get a good level surface for your finish to look good if you are doing a high gloss. Satins are a bit more forgiving. On the neck ,while I am not a fan of oil finishes or tung oil on the body , the neck is a different animal. I like a satin finish on a neck . Gloss finishes tend to get grabby when your hands sweat.
take your time , follow the finish instruction and please , allow ample cure time before buffing out. I often spend more time on finishing than building. The fit and finish is what will make your guitar look good.
Have fun and keep the strings on the out side
john

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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

I would echo what John said about taking your time, and add to that how important it is to take care of problems and details as they arise, as early as possible in the finishing process. Don't expect that a little irregularity "won't show". After you've done a few, you'll find out what you can get away with, but don't make assumptions now.

I've used:

KTM9, padded on. Pretty good results, but a little on the soft side, and I don't much like how it feels on the neck. Doesn't wear too well. No decades-long track record, not easily repaired.

French polished shellac. Beautiful finish, looks deep even applied thin. Lots of work, but a rewarding process. Lots of steps. Sessions are often fairly short; each session has almost no prep and no cleanup. Very repairable. Cheap, almost no equipment needed. A bit on the fragile side, not as tough as nitro or the modern finishes, but becomes more durable with age, and has been around for centuries. For me, the most "craftsman-like" finish I've tried.

Behlen's Rockhard Tabletop Varnish, brushed on. Tough, with a beautiful tint, though a bit less color would be good. Not so repairable. A little tricky to apply to get minimal witness lines while sanding. My favorite so far.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

98% of the time I use nitrocellulose lacquer. It is not hard to apply and the results are always stunning. My complete "how to spray lacquer" is at this location: http://www.wellsguitars.com/Articles/Lacquer_Finishing.htm
Enjoy!

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Sylvan
http://www.wellsguitars.com

I have one guitar that I French polished in 2005, so it's had 4 years to harden. I play with a heavy flatpick, but I don't hit the top of the guitar with the pick, so I had not scratched it, and the top was looking very good, with only a bit of dullness in the area where my right arm rests. About a week ago I lent the guitar to a friend for a day and it came back with several scratches in the top. This taught me something about the fragility of FP, even after a few years, which I might never have discovered if it wasn't for my helpful friend! FP is great in many ways, but this definitely went down in my book as a point against it for steel string guitars. Yeah, it can be repaired, but working around the bridge and pickguard will make that difficult. I'll probably never get around to it.

I would take any claims of a difference in sound, when compared to other thinly applied finishes, with a grain of salt. There are just too many absolutely fantastic sounding guitars with many different finishes on them.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

I've tried a lot of different finishes over the years, and there are few of rules of thumb that come to mind.
1) They all take about the same amount of time from start to finish.
2) The most important step, by far, is the surface prep.
3) There is no 'perfect' finish. They all have drawbacks and advantages, and all you can do is find the one that comes close to meeting your requirements without having any faults that you can't tolerate.

Nitro is the 'standard' for a reason, but it's not a reason that might sway you as an individual maker. If you have a good spray rig and the requisite skill it goes on nicely, dries reliably and hard, and looks terrific when buffed up. Touch ups and new coats 'burn in' perfectly. Now for the drawbacks.

Nitro is, itself, the 'little brother to a high explosive', and the solvents used are very flammable. Of course, any flammable substance when finely divided in air can explode, so this stuff is a first-class fire hazard. The requirements for a _legal_ spray setup are formidable, and expensive, at least around here. Yeah, you can get away with spraying it outdoors, but that's not nice either. All of the solvents used are toxic in concentrations you can't even smell, for one thing; there goes your 'green' rating. The nitrated part of the cellulose molecules that make the stuff soluble at all is chemically unstable. That's why nitro turns orange, shrinks, and cracks with age. The nitrate fumes can etch plated parts, too. I used to use nitro; now I can hardly open a can without getting a headache.

Shellac has some of the advantages of nitro, in that, as a solvent release finish, it 'burns in' perfectly. It's actually a fairly hard finish, and more resistant to chipping than nitro. Shellac also gets better, harder and more solvent resistant, with age, although it takes about 75 years for the process to run it's course. You can brush shellac if you want to thicker build-up, although its a bit tricky to get a really level finish that way. A few drops of kerosene or spike oil (kero is a lot cheaper) in a pint of shellac make the brushing go better. I've heard of people spraying shellac by adding some acetone, but I've never tried it.

Shellac is soluble in alcohol or alkaline water solutions. This is both an advantage and a drawback. Alcohol is not nearly as poisonous as lacquer thinner, although some of the stuff they put in to denature it is pretty bad. You can get 190 proof grain alky in some states, and that won't be as bad for your health, although your wallet might object to paying $15-20 a quart for shellac thinner. Put a little in your coffee and the problem seems less pressing, though.

The drawback of the solvents used with shellac is that they're a lot more common than, say, the toluene or MEK used with nitro. For many people sweat is an alkaline water solution, or so it seems. Also, since alcohol is less volatile than lacquer thinner, it takes a given thickness of shellac longer to fully harden than the same thickness of lacquer. Shellac also has a shelf live, both dried and mixed, and it can be drastically slowed in hardening if the humidity is high.

French polish is a method of applying shellac (or other resins) with a pad, to get the thinnest possible coat. Because there's less of it, your'e adding less weight, and that can help the sound, particularly on something like a classical guitar top. There are a few drawbacks, of course. You can't hide ANYTHING under .002" of clear finish; your surface prep has to be perfect. That thin coating cant protect the wood much against scratches or dents; there are few things as fragile as a cedar top with a new French polish finish. Sincemost players these days are used to industrial type finishes that wear relatively like iron, it's a given that taking a guitar with an FP'd top to a show guarantees a harvest of dings. Finally, an FP job always looks a little better the longer you spend on it. Thus the term 'French polish finish' is an oxymoron; once you start you'll never really finish. That siad, you can do an adequate 'quickie' job with FP faster than almost any other finish, so it has the shortest lead time.

'Varnish' is really a whole class of things, traditionally made by cooking a drying oil and a resin together. There are at least a half dozen different oils, and a couple of dozen resins, that can be used, and the product will vary depending on the ingredients, the proportions, the cooking time and temperature, and probably a bunch of other things as well.

Recently I've been using Behlen's 'Rockhard Table Top' varnish. The first coat can take as much as a week to fully cure over some woods, but once it has subsequent coats will dry in less than four hours. UV light helps that first coat to set. I thin it with about 25% of their proprietary reducer, 5% acetone, and a little kerosene as a brushing agent, and apply 5-10 thin coats. Make sure you do the last two coats the same day, and allow it to cure for t least a couple of weeks before leveling and polishing, to avoid witness lines. This goes on thicker than FP, and it's a pretty tough finish as well, so it's much better protection.

True Oil is essentially a thin varnish that you wipe on. In that sense it'slike FP; you can just keep putting it on and it keeps looking better. You can do a minimal coat quickly, and, of course, get less protection.

All of the varnishes I've tried keep shrinking for at least a couple of months after they're applied, so if you want that perfectly level 'Lexus look' you've got a bit of a wait. I like the look of wood grain, myself. Any varnish will harden in the can if there's air in there. I add marbles as I go; some folks swear by 'Bloxygen'. The only way to get all of the varnish outof the brush is to wash it well with soap and water. I spend about as long cleaning the brush as I do actually putting on varnish. Lately I've been using a 1/2" camel hair brush, and am on the lookout for a 1" one; it gives a nice smooth coat.

Most of the polyurethanes I've tried seem to stick better to themselves than they do to the wood. They tend to peel over time like a bad sunburn.

All the experinience I've had personally with water base finishes was several years ago, and it was all bad. One of my students has used a KTM product, and got good results, but it was very hard stuff to polish out.

I totally agree with that.
I think any finish applied too thick has the potential of dampening the tone, whereas it's lacquer, poly or anything else. I'm always surprised when someone claims to hear the difference between materials with a finish that's probably not over .004" thick. Personally I don't.

Tru-oil for the neck really feels good and is easy to apply, I would think it's a little too soft for the body. Behlen's rockhard would be better, and it also feels great on the neck. Even buffed it doesn't seem to stick or drag.

Nitro-cellulose lacquer is somewhat traditional now. The stuff is pretty toxic and lingers a long time so without a proper spray booth and a place to hang the guitar while it cures it's not really recommended.

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Laurent Brondel
West Paris, Maine - USA
http://www.laurentbrondel.com/

That is an option I hadn't considered and will probably use on number 2, I'm leaning towards French polish with a satin finish at the moment as there are a lot of lumps and bumps in the back in places there the wood was originally rippled and I thought it'd all pull out and sand out once braced so a satin finish may be the way to go to hide it?

Thanks once again guys a vast pool of knowledge here it's true

John

_________________
Formerly JJH

I learn more from my mistakes than my successes

No truer words were ever spoken, John!

Ken

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http://www.casperguitar.com

Gonna pore fill later today or tomorrow now, and wondered when you use your west systems if you did the top as well and do you need to stain after filling, and can I fill ripples in the back using that to build up to the level of the rest of the back, probably a 0.060 ripple and the other thing I wondered why don't the pores go white after filling as that is what sanded west systems look like.

I also noticed Sylvan Wells uses a medium super glue to fill and wondered if otheres used it and wha are the advantages?

Also saw a lovely 10 string baroque guitar yesterday and that was just finished with egg white!

_________________
Formerly JJH

I learn more from my mistakes than my successes

Alan
thanks for your post , I always enjoy the details and explanations. I hope to see you at ASIA in June. I have used schellac as a seal coat but never tried it as a final finish . Can you tell me if this glosses well?
thanks again Alan
john

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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

After years of using KTM I have switched to Stew Mac's Color Tone water base finish and so far I really like the results. I always struggled with KTM. The Color Tone brushes on nicely and polishes out very well. I have used it on the last 4 or 5 guitars I have built so they have not stood the test of time yet but so far I have no complaints. I have used Nitro in the past as well. But my workshop is in my house and with waterbase finishing I can finish quickly, safely and easily any time of the year right in my shop.

And yes finishing is always frustrating to me and it almost always takes longer to finish a guitar then to build one, at least in duration of time not necessarily hours put into it. I don't wet sand and polish out till at least three weeks after the last coat is on - four weeks even better.

"You can get 190 proof grain alky in some states, and that won't be as bad for your health, although your wallet might object to paying $15-20 a quart for shellac thinner. Put a little in your coffee and the problem seems less pressing, though."

Alan,
Thanks for the usual thorough explanation. I mean all of it not just the coffee part.
Link

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

John asked:
"Can you tell me if this glosses well? "

Shellac is a nice glossy finish, but not as glossy as some. Partly this has to do with hardness, and partly with index of refraction. Basically, the higher the IR the more light will be reflected from the surface at any given level of smoothness. That's why they put lead in lead crystal glass; the higher density gives it a higher IR and more sparkle.

The index of refraction also relates to how 'wet' or 'deep' the finish looks. If you can find a finish that exactly matches the IR of the cellulose in the wood the light penetrates better, and it looks more 'alive' and the color is more 'saturated'. One of the problems with a lot of the early water based finishes was that the water would wet the surface rather than the finish, and you'd end up with a very 'cloudy' finish that was obviously just on the surface. That's one reason they use epoxy or other fillers before putting on the water born.

It seems to me that nitro has a better IR match than shellac, although the difference is small. The Behlen's varnish, and many other oil-resin varnishes, match more closely, and look 'deeper'. Some of the UV cure stuff I've seen is terrific that way.

One other thing I left out the other day was 'damping'; the amount of vibration energy the finish will dissipate. This is a real issue if you're trying, as on a classical top, to preserve all of the treble you can. From the measurements I've seen, nitro has about the lowest damping factor; in fact, it's lower than that of spruce across the grain. Shellac also has low damping. Oil has high damping, and any finish that has oil in it will tend to have higher damping than one that does not. I find that the damping of 'Rockhard' varnish is not a problem on steel string tops. However, if I'm making a classical with a really pretty B&S that I'd like to show off with the varnish, I'll FP the top for the sake of the tone.

There is no need for a separate sealer coat under a solvent based finish. There is a need for raising grain and sanding it back, though. One way to do this is by coating first with something that sands reasonably well, like shellac. That coat often gets called a sealer, but it can be completely sanded off and no further sealing is needed before applying the solvent based finish.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Right guys decision made now French polish it is, using west systems as a pore filler, so any hint and tips will be greatly received I'd like to thank everyone here for there help, and opinions, the decision was made basically guitar one is going to be my guitar to learn on and I would like to french polish at least one guitar particularly as it really a rough looking thing, I can only improve it and Mat thanks for the heads up on the Rustins Plastic Coat thats what number 2 will be finished with.

Still sanding and scraping at the moment and I've already sanded through the side in a tiny patch you can see the linings and its dangerously thin in another. I regret now not buying the proper woods in away and using non book matched and slab saw stuff but even if you include glue, truss rod, and top I've only spent £20 and I've learnt a hell of a lot and had a lot of fun on the way and gained a lot of experience in how to correct my mistakes! I also measured the ripples in the back and they 0.040" can I build these up with either superglue or epoxy in the pore filling stage, so I have a level surface to work from, what'd you guys suggest?

_________________
Formerly JJH

I learn more from my mistakes than my successes

John,

Since you've decided to FP, I imagine Michael Payne will drop by sometime soon. Regardless, if you search the archives, you'll find a number of informative posts from him on the subject.

As for my 2 cents, I use devcon 5 minute epoxy to pore fill before french polishing. I was talking about this with Monica Esparza a few weeks ago (classical builder here in socal) and she does something similar. However, she epoxy's directly onto the wood without a seal coat of shellac, whereas I seal with shellac first. She'd heard from Rick Turner that filling directly onto wood is the way to go...I don't know what's better. I'd be happy to hear opinions.

To apply the epoxy, I use a dulled razor blade at the recommendation of Bob Millburn. Others use a credit card edge, but I find that the razor blade leaves very little epoxy on the wood, which makes for less sanding. The technique is basically: mix a little bit of epoxy, put a dollop on the area of the guitar you've chosen to work on (divide into rather small sections), then scrape the epoxy into the pores going along the grain. When finished, sand with 320 grit sandpaper, but don't over-sand. Also REMEMBER TO WEAR A MASK, GLOVES, AND TO VENTILATE!!!

As for the FP'ing itself, I recommend the Millburn tutorial. I started with it and learned as I went. I would recommend that you "spirit off" after each FP session (M. Payne's recommendation). It'll make for less level sanding.

Anyway, as I said, that's just my 2 cents. Hope it helps.