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TruOil is a hard finish when applied thick enough to polish.
I didn't do this Tele, but it looks great with a TruOil finish.

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"Act your age, not your shoe size" - Prince

Thanks Chris. I put many thin coats of tru Oil, probably 20 or so. I like to level sand with Assilex papers in between, say every 4 or so coats. I then let it cure for 30 days or so. then finish sand and buff. Its a nice finish, but I find it does dent pretty easily for some reason, I find it more forgiving on acoustic guitars than electric - maybe I am just harder on electric guitars . I like the results I get with our oil. But mainly looking to see if I can do a hand applied finish, with good results, that would be harder and more durable than Tru Oil.

Thank!

Glenn

What were the results of the recently mentioned Osmo applications? Anybody have feedback on that finish?

jfmckenna asked:
"Alan do you brush the varnish on?"

Yes. On open pored woods, such as that BRW I fill first, using shellac/pumice as for FP. That typically takes two or three sessions, and it gets sanded back to the wood with 220 paper so there is no shellac on the surface.

This is followed by three brushed coats of varnish. I use a 1" 'camel hair' brush; a soft natural bristle. This allows me to pull the varnish on quite thin, and minimizes runs and sags. As a floor finish this stuff is designed to go on a flat, level surface and flow out, so you have to apply it thin. There is always enough air space in the filler that it absorbs a bit of varnish, which shrinks as it cures, so I like to allow these 'filler' coats to cure for a few weeks in possible. They are then sanded back to the wood again.

I'll note that, as with all oil-resin varnishes, the first coat can take some time to cure. This will be particularly true if the wood is at all oily. Sometimes the first coat cures right away, and sometimes it can take a week or more. There's no rhyme or reason I can see; it all depends on how much non-drying oil is in the particular piece of wood. Some, such as Macassar ebony, tend to be problematic all the time, while others, like IRW, are slow to cure sometimes, or in spots, but not others. You have to allow the first coat to fully cure. A fresh coat on top of uncured varnish seems to seal the base coat off from the air that it needs to set up; the base never curs right, and eventually the whole thing can peel like a bad sun burn. UV light helps a lot. It reacts with the VOC given off by the varnish to produce ozone, which, in turn, reacts more strongly with the oil in the varnish and cures it. With this varnish, once the first coat has set up you can put on one or even two coats a day.

With varnish the re-coat time is important. Because it cures by a chemical reaction the dry film is not the same thing as what's in the can, so the new coat won't 'burn in'. It's best to add the next coat as soon as the prior one has cured enough to 'dust up' when it's sanded. I hit each coat quickly with #400 dry sandpaper to cut back any dust and produce a higher surface energy.

Once the fill coats have been sanded back to the wood I can brush on one or two coats a day, as I said. This vanish goes on very thin, and, like all varnishes, shrinks back as it cures. I'll put on 8-10 coats of varnish after the fill coats. This takes a few days, and I then allow it to cure for at least a week, and not more than a month.

I've been using 'Unigrit' sandpaper that I get at the auto parts store: it's Japanese made, and marketed by Meguires. They use some sort of process to sort out the grit particles so that they're more uniform than most, so it doesn't tend to leave large scratches. If I've been careful I can level up with #2500 paper, wet; otherwise I'll start with #1500 to knock back any sags and get the hard surface off. The longer this stuff cures the harder it gets, so you don't want to wait too long!

If I sand through I go over the whole surface with #400 dry paper, and then put on at least three more coats of varnish. The wet sanded surface seems to have inherently low surface energy, and now coats don't stick well. Also, if you can, avoid the blue-grey stearated sand papers, which sometimes also inhibit adhesion.

Once the surface is leveled up wit sandpaper I go to FFFF pumice and rotten stone, using water as a lube. Both of these are fairly soft abrasives, and cut themselves down pretty fast, so the longer you rub the shinier the surface gets. Rotten stone is not much harder than the varnish, so you have to rub hard. After those I finish up with Novus polishes, #2 and #3. I have found Meguiar's auto polishes a bit too aggressive in the past, although they may work well enough with this hard varnish.

I have never had much luck with power buffing oil varnishes. It's probably more a matter of my own lack of skill: I always manage to burn through on a corner someplace and end up having to sand back and re-finish. Hand polishing takes a lot of time and effort, but not as much as refinishing.

I'll note that oil and oil-resin finishes are tough and flexible. They can be hard to scratch, but prone to denting. This is particularly true if they're put on thin, as they should be on an acoustic guitar. There is no finish that will do much to resist dents at .0025" thick: it's just not possible.

Endurovar and EM6000 are both small shop friendly finishes and it's possible to get a really nice finish with either of them. Both can be applied just fine by brushing so no need for a spray booth or spray equipment. I like both of them, but I'm using Endurovar for the foreseeable future.

EM6000:
- A really big plus is repairability. I've had several "opportunities" to repair EM6000 and the repairs are always invisible. Newly applied finish blends into the old finish with no witness lines.
- Many users have reported a slight bluish cast that's visible in the right light particularly on dark woods like rosewood. I used it on a bunch of different woods including several dark woods and never saw it so, although it does happen, it's not a universal problem.
- EM6000 has a lower solids content than Endurovar and it brushes on thinner so it builds much slower and takes many more coats to get sufficient build.
- You have to add retarder for brushing to work, so it takes longer for each coat to dry than for Endurovar (which doesn't require retarder) so the intervals between coats are significantly longer and that adds up to a longer total time to get the finish on.
- It sands and buffs nicely.

Endurovar:
- Builds much faster than EM6000 when brushing it on.
- I've never heard anyone report any bluish cast.
- No need for retarder for brushing.
- It seems to cure harder than EM6000.
- Sands and buffs nicely.
- I don't know how it is for repairability.
- As Clay mentioned, it has a slight amber tint to it. That hasn't been a problem for me, but I haven't tried to use it over something pure white like white plastic binding where you wouldn't necessarily want any alteration of the color.

For pore filler I use epoxy. I switched from Z-poxy to SilverTip a couple years ago. Both have worked really well for me as pore fillers. I don't sand the epoxy back to the wood. I leave a very thin coat on because I really like how epoxy enhances the grain in the wood. So much so that I even use it on woods that don't need pore filling. SilverTip is clear while Z-poxy has a distinct tint to it, which some people see as a disadvantage. If you sand back to wood though, that tint isn't an issue. Even if you don't sand back to wood, the epoxy coat is so thin that the tint has very little effect. The disadvantages of Z-poxy for me are that it smells really bad in a toxic sort of way and you have to apply it at 70 degrees or higher. It won't cure properly below that. My shop is often in the low 60s. SilverTip isn't temperature sensitive and it doesn't smell like it wants to kill you.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

I have recently purchased this https://www.woodessence.com/Guitar-Inst ... ent-Finish as I am in Atlantic Canada and the winter weather outside is not condusive to spraying for more than half the year. I also will be grabbing one of these in order to keep the spray contained. (You can slide a furnace filter and box fan in the back as well) https://www.amazon.ca/HomeRight-C900051 ... 0059&psc=1
It says you can brush it as well will their retarder. Just have to finish the construction part now! ;o)

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Guitar Building = Continuous Improvement Process

Raymond—

Just a heads up that I found the spraying tents to be pretty useless. They are very flimsy and tear easily, and mating with a fan was not great. You might as well just drape tarps to catch overspray. This was my experience, anyway.

Alan after you pore fill and sand back wouldn't a spit coat of shellac seal the wood so your first coat of varnish would not take so long to cure? Or are you worried about the compatibility of shellac under the varnish?

Thanks Chris!
That’s one of mine.
About 8 coats of tru oil.
Wet sanded with the oil around coat 4. Wipe on, wipe off.
Last 2 coats were thinned with mineral spirits.
This was not polished.

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wah
Wah-wah-wah-wah
Wah

Brother, you set the bar high on that one. I would love to do a TruOil finish that looks that good.

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"Act your age, not your shoe size" - Prince

I've used Z-poxy on everything since guitar #1 because I also like (love) the way it pops the grain. Does Silvertip have the same effect?

Yes.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Agreed, Silver Tip gives wood a beautiful wet look.

Me thinks that there is another question that goes along with small shop finishes and that is finishes that will be appropriate for the intended purpose.

If one is going to be commercial there is an expectation if you sell your guitars that not only will they be worthy of the hard earned coin of others but that you, YOU know what you are doing and do it very well.

When I hung out my builder shingle and ramped up to 24 guitars a year I shot nitro and did it myself. Prior I had used Joe White and before him Tony Ferguson. Both Tony and Joe do superb work but I had to get the costs out of my instruments to make a go of it commercially so I shot my own nitro.

My finishes were very good, as good as Martin and better than g*bson with better consistency of film thickness and better buffed out too. My costs were mouse nuts compared to outsourcing and the results were a nice, high gloss that people are accustomed to seeing on guitars.

There is a reason why nitro has stood the test of time in Lutherie and that is because it's easy, sort of.... has a fast learning curve, sort of.... does not require (but you should) expensive equipment for safety or application and it's cheap.

So I vote for nitro IF.... the instruments are intending to be sold to an unknown person who may gig or not.

Sonically a French polished top is desirable too but not for a gigging musician that gets beer bottles thrown at them.....

Nitro can be sprayed in reasonably humid weather (up around 70% RH) with appropriate strategies in place. Even if the strategies fail and the dreaded blush appears a quick misting with a rattle can of blush eraser solves the problem very quickly. This works for my small shop finishing needs.

Regarding fit for purpose finishes, in the last week I’ve had two 60+ year old Japanese classical guitars through the shop for minor work, both from makers that apparently used some kind of hand-rubbed “cashew oil varnish.” The finish on both still looked superb 60 years on, was very thin with excellent gloss and no age related cloudiness, haze, checking or degradation that I could find. I’ve never seen a nitro finish look anything like this good at 60 years of age.

If I was going to switch from spraying to a hand applied finish I’d be trying to get my hands on some of this cashew stuff to experiment with.

Hesh—

So, we can glean from your post that you feel that nitrocellulose lacquer is appropriate for the intended purpose, and a French polished top is not. Fair enough. What about the other finishes that are being used for guitars right now, like oil varnish, waterborne lacquer, pre or post catalyzed finishes, UV cured finishes, modified shellac, etc.? Are there any that you think are, or aren’t, appropriate for the intended purpose? Keeping in mind, of course, the point of the OP (Glenn) starting this thread in the first place. He is looking for finishes that don’t have to be sprayed. Any suggestions, yay or nay, beyond nitro and shellac?

I can only comment Don buddy on what concerns me, serviceability. If you want me to put on my other hat the ole GE business development guy other finishes will be judged by the market, who you are peddling your stuff too. Again though we are used to shiny guitars. On the OLF back in the day we used to say whomever decided that guitars should be shiny should be dug up and shot

Cat Poly is likely the toughest finish out there but Joe White sprayed it and it likely has to be strayed. Cat Urethane same thing.

So if it can't be sprayed because of the complications associated with the equipment necessary why are we considering UV cured, that has heavy overhead in ancillary equipment and risk too.

I would like to know the aversion to spraying because I have a guitar upstairs that was finished with Stew Mack rattle can nitro and it's beautiful nearly 20 years later. No extra equipment, sprayed in in my bathroom (not a good idea don't do this at home) and it came out great.

Todd Stock when he was here once posted that the problem with the rattle can stuff is the higher solids content and he's right. How that manifests is a bit of cloudiness in the appearance if you do too many coats. But I did nine coats and did not have the problem that would result from rattle can with more coats as Todd rightly said.

And not to insult anyone but many of you guys like your waterborne or varnishes and good for you, more power to ya. Consider your instrument next to someone else's in the marketplace and the competition has a flawless, gloss finish. This is the market expectation that I speak of with the bottom line being it may not be about what you want to use or what you want to avoid it may be all about market expectations.

I can spot water based a mile away and so can most of us who work in the trade. It's often water white and rather unnatural in appearance for nitro snobs like me.

French polished shellac is an incredible finish, better than nitro but it has to be for an adult who will care for the instrument and does not do Townshend windmills every night before bed.

Remember too if the finish for better or worse that you select does not stand up to reasonable wear and use and you sell your instruments you may have some exposure in terms of warranty claims.

And lastly this question has been asked dozens and dozens of times as people come and go and everyone seemingly wants to avoid an explosion proof fan and lighting (we have both in our spray booth). Bottom line in my experience is that nitro is still mostly king and market perceptions drive this especially traditionalists such as the Martin and g*bson crowd. Deviate and your stuff may not be well received.

So no Don and I just reread my reply and your question, in my experience factoring in that market expectation and all the other factors guitar building has some things associated with it that you pretty much must do unless you are an island unto yourself and have a private market for your stuff that no one else can access.

To simply if someone asked me about a finish appropriate for commercial guitar production that is not sprayed what would it be? My answer would be it needs to be sprayed or French polished shellac. And again you can do varnishes and oils and such but your stuff may not sell because of that market expectation.

Take a look at the archives and do some searching again this has been asked many times and I bring this up because every solution mentioned in the past beyond shellac and nitro or cat poly and cat urethane which are sprayed has not remained in favor over time for good reason.

I remember 20 years ago when the people building swore by enduro var.... for floors. Never hear of it anymore just like the others. True oil has prevailed but the results in my experience are not equal to nitro and FP shellac.

When my client says to me what is the best sound hole pup and I say forget about sound hole pups they all suck (and they do...) and recommend for them a K&K for $100 or an Anthem for $260 or a Lyric for $200 I am not ignoring their original request for a sound hole pup recommendation. They asked me and in my experience they won't be happy with the results of a sound hole pup so I recommend a better solution.

That's what I have done here. If you want a padded or brushed or simply not sprayed on finish that is not nitro or FP shellac and if you plan on being commercial and selling there is nothing else that I would recommend.

You have to break some eggs to make scrambled eggs.

I'll add I feel the same way about people who think that they can get around strict RH control by building and storing in a box.... Good luck with that, you have to break some eggs to make scrambled eggs...

PS: You need RH control to spray nitro in addition to spray equipment.

The only sound hole pickup I have ever used that sounded "acousticy" was the venerable Bill Lawrence that's been sold for over 40 years.

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"Act your age, not your shoe size" - Prince

I may be an old cynic, but unless you have a private market you’re probably not selling guitars.

You are not going to compete head to head with Gibson or Taylor for people who want that, no matter how much better your mousetrap. Bespoke watch makers don’t compete with Rolex. They find a niche or drive for Uber.

Also, most guitars are wall art. It will be decades before someone notices problems with finish, and by then most of us will be dead. I appreciate that Hesh prefaces his post with the acknowledgment that he’s a carpenter so all problems are nails, but how many of you have had to fix finish problems? That’s not a rhetorical question. I honestly don’t know if that is a problem. Perhaps people could share their real world experiences as builders who have had to fix finish problems? I’ve only released a couple of dozen into the wild, but none have ever come back for finish problems, and I’ve done just about everything posted here: sprayed nitro, Enduro, FP shellac, EM6000, TruOil, etc.

That said, people love high gloss. When I first started building twenty plus years ago my teacher said, “tone thrills, but finish sells”.

If your private market loves some aspect of your builds, and don’t need a perfect high gloss finish, then I think all these finishes work. Heck, I’ve seen Rubio Monocoat used. Wipe on one coat, wipe off excess, buff lightly. If you need a high gloss high durability finish that looks like a Gibson, you probably are going to have to spray like Gibson. Of all the techniques I’ve tried, only sprayed nitro looked like sprayed nitro. Tant pis.


Sent from my iPhone using Tapatalk Pro

Hesh - I generally respect your opinions, but IMO you are off the mark here in several ways.

The original question was about small shop friendly finishes that don't have to be sprayed. That makes nitro irrelevant to this thread.

The idea that one has to use nitro if you are going to sell instruments you build is detached from the real world. As just one example. John Greven has been producing high end guitars finished with Endurovar for many years. You can read about it in his two-part American Lutherie article from 2014 (issues 117 and 118) titled "How I Build Forty-Eight Guitars a Year with Almost No Tooling". He was still using Endurovar three years ago when he gave a presentation to the Seattle Luthiers Group. I've played three of his guitars and they were excellent instruments in every way, including the finish. John has been a professional builder for 60 years and has built over 2000 guitars. It has worked for him so there's no reason it can't work for other builders. I know other builders who have many paying clients who are very happy with their guitars finished with Endurovar or EM6000.

"And not to insult anyone but many of you guys like your waterborne or varnishes and good for you, more power to ya. Consider your instrument next to someone else's in the marketplace and the competition has a flawless, gloss finish." This is off the mark too. The implication here is that a flawless gloss finish is not possible with waterborne finishes. Dead wrong. The idea that a flawless glossy finish can't be obtained without spraying is also dead wrong.

If anyone's breaking eggs, it's the builders who are moving beyond nitro to good alternatives.

I agree with rlrhett's point that small shop builders are largely not competing with the likes of Martin, Gibson, Talyor, Collings, etc. The people who buy from small shop builders are generally looking for something that is not from the large scale factory builders and don't particularly care if the finish is nitro or not. Not everybody who is looking to buy a good guitar has swallowed the marketing claims from the big shops about how magically essential nitro is. If an instrument hits all the marks for what they're looking for in sound, playability, and appearance, they are good to go.

There's no doubt that nitro is a good finish, but it's not the only viable game in town, especially when it comes to small shops.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

I wish to have it noted in the record that I merely asked the question. I take no responsibility for, nor do I comment upon at this time, the responses given.

For sheer optical clarity, urethane wins hands down. Freshly buffed nitro also looks fantastic as does polyester when done to high standards. These 3 finishes are your gold standard and what high-end customers will ultimately expect in the ultimate guitar created by the best builders in the world (Guess what finish Traugott uses on his guitars?). The actual truth is that almost no one can look at a finished piece of wood and identify whether it is urethane, nitro, or polyester. Side by side comparisons of the finish will show subtle differences, however.

Oil varnish can also work well. It has a certain look and thanks to Collings reputation with the finish material - you have some degree of wiggle room and acceptance by players of a non-perfect surface (within reason, of course). Varnish is amber tho' and this does create a certain look. It has been used very successfully by several highly regarded builders. My experience with the finish is that it is a lesser option to an ultra thin urethane finish -- but an ultra thin urethane finish is not an easy thing to do. Between nitro or oil varnish, I'm not sure which I'd chose ... probably varnish.

Shellac can also work quite well but requires very specific customers with informed expectations. IMO, it is the only "heirloom" quality finish.

You can read my thoughts on different finish materials below. I spent over a year experimenting with numerous finish materials. It was a nightmare and nearly broke my business but what I can tell you is that I am able to spray a 2k urethane in an attached garage with a knockdown spray booth .... safely. Having used polyester, nitro, EM6000, Tru Oil, Oil Varnish (Murdoch's Uralkyd 500), French Polish, and urethane --- it is my opinion that a thin urethane finish wins by a landslide but with some caveats. ***All this information is for extremely responsive steel string guitars --- classical guitars may react differently and so I won't presume a thin urethane would work as well as varnish or shellac.

http://fayguitars.com/Guitars/finish.html

If you don't want to mess with spraying -- then do the oil varnish and follow the excellent information provided by Al Carruth, Sexauer, or Brondel.

IF you build traditional guitars, then you must use nitro to make them salable.

If you just build for fun ... then most of the available finish materials can absolutely work. Each finish is like a system ... so stick with it and learn it and improve. Again, I would probably recommend the oil varnish but it is time consuming and somewhat challenging. It is possible that one of the waterborne finishes will give you a better end product due to the easier learning curve. And that's the whole point of this thread .. lots of good information was presented.

If you sell your guitars (and aren't using French Polish, oil varnish, urethane, nitro, or polyester), then just be aware that you are providing your customers will lesser options than a company like Collings or Martin provides. It isn't about "different" but truly about using a lesser quality finish. Guitar building isn't easy ... so I get it ... but my advice is to eventually step up to a higher quality finish. It will help your brand and leave your clients happier in the long run.

The above is just my opinion and I offer it respectfully to each of you. There is lots of room on the table for different perspectives. But by god, did I struggle over this "finish stuff" ... so I hope what I personally learned may be of use.

All the Best,
Simon

Simon,

I’m curious as to what film thickness you’re able to get, especially on the top?

Hi Ed,
I'm getting between 0.002" to 0.003" -- this measurement is from frisket tape with the finish on top. I get 0.004" (at my very worst) and the body still was very vibrant and much better than when I used polyester. I try to spray a bit more at the neck joint tho' .. so that is always around 3 to 4 mils at the binding edge there. However, I want it thin especially around the perimeter below the soundhole.

How thin I can get depends on how well I can sand the 1st urethane spray session. I put a 2 mil frisket tape on the fretboard and bridge location. I spray extremely evenly with good technique. I ensure that I level to the frisket tape and then keep on going. It's basically a game of do I burn through or stop in time. I'm still working at getting better at this part but the sanding of the 1st urethane session is how you get the finish ridiculously thin. The finish needs to be absolutely perfect after this step and before you spray the final coats. The final application is to spray 3 coats at 1mil dry thickness. I think I end up eliminating 1.5 mils during the sanding and buffing process. So the thinner I can get that 1st layer is where the real skill comes in. Tim McKnight sprays only 2 final coats for the top. He says he can get 1.5 mils but that's so thin. I almost want a bit more finish in case someone wants to come along later and polish out scratches or something.

I'm using the SimTec urethane now and like it.


Give me a call and I'll go over my process with you. Phone numbers on the bottom of my site. I am just ridiculously pleased with how well my finishes are turning out and the resulting tone of my guitars. The only thing I'm struggling a bit with is the occasional pinhole. I'm using a FUJI HVLP which makes the process harder than with a compressor but I expect I'll figure out things out as I go on. As it stands, the finish is good enough to satisfy my OCD nature when it comes to my guitars.