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Well, isn't funny how things come FULL circle. Here's what I mean:
As a new builder I started with shellac, trying to French polish. I went through the Tom Bills class and took lots of notes (because you can't download the dang thing; subscription only which is great for avoiding piracy but terrible if you want to remember any of it). I got a pretty good finish.

Over the next 14 guitars I tried several other finishing methods from nitro to EM6000 (which is pretty dang good honestly).

Fast forward to year 3. I'm on guitar #16 and thinking of trying to French polish again. I really believe my patience in the process has grown since I've been building, and think it will yield a better FP.
I'm making a guitar that will need a lighter finish because of some design features (I want to keep it as free as possible), but I think I need a refresher course on the process; especially pore filling technique, what types of oils to add when - vegetable - walnut and such, and that kind of thing.

So, can anyone recommend a good course? Download of DVD? I know Robbie has one, that may be on sale, then there's the non-downloadable Bills (which is EXCELLENT and is REALLY well produced). I appreciate all the experience that this forum offers.

I can't imagine trying to get better at this in the internet dark ages or before (pre 80s).

Thanks.
B. Snow

Snow—

I French Polished my first 7 guitars, with varying success. I’m in the middle of experimenting with an epoxy pore fill (Silvertip) and Enduro Var, both brushed on. I like this a lot. It is better protection for less work.

If I go back to French Polishing, I will pore fill with epoxy or CA. Traditional pore filling was the most frustrating and inconsistent part of French Polishing for me. Once I got a good pore fill (WHEN I got a good pore fill), the rest was pretty easy. I suspect it is the same for most folks. This is why some of the serious French Polishers like the Milburns and Cyndy Burton have moved to a more modern (epoxy or CA) pore fill.

I justify this departure from tradition because the expectation for a glass smooth finish was not the norm for guitars made pursuant to the tradition, but it is the expectation now. So, a more foolproof way of getting that glass smooth finish, one that depends on materials that did not exist before, is a good idea, in my view.

FP is pretty much the only finish I use now and like you I've tried a bunch of them. I learned from the somewhat famous Milbourne tutorial that you can still find on line here: https://www.guitarsint.com/article/Intr ... al_Guitars.

Since then though, and probably like everyone who has ever French Polished a guitar or a table for that matter, I've modified it to my own technique and style and combined it with other tutorials from accomplished finishers.

One of which came from the old LMI catalog in an article written by John Greven which was to mix walnut oil in with the shellac making it almost more like a varnish. I don't actually measure the oil but it's a considerable bit, probably about 10-15% of the mix. Walnut oil is a drying oil that becomes a part of the finish and it also makes the process of French Polishing with a mouse a LOT easier and less sticky.

With this mixture and the technique I've developed I don't even have to polish out the finish. I simply glaze coat and am done with a nice reflective mirror finish. It's nothing like a UV cured Polyester gloss mirror finish but I never liked that anyway.

As for pore filling my favorite now is CA. I tried epoxy once and I'll never use it again, what a mess! I've also used and will definitely use again egg whites. No matter what filler I use I always sand back to wood leaving the pores filled.

To speed up the FP finish I use a nice quality brush and brush on the first 3 coats. Then lightly sand back flat and begin the FP process. This significantly reduces the time required to get the finish done.

"To speed up the FP finish I use a nice quality brush and brush on the first 3 coats. Then lightly sand back flat and begin the FP process. This significantly reduces the time required to get the finish done."

Thanks for the technique there. I have 2 sprayed shellac guitars that didn't work out, and plan to sand way back with 400, then FP. Might be my default finishing technique, for acoustics.
Anyway, Snow, I did look at a few vids years ago, and let the method soak in, and go by what you teach yourself by your own results.
I don't like to pore fill, and just let the finish be the pore fill.
I know most folks here will not agree with that, oh well.
I might add, I don't go for mirror finish, so....
I get uncomfortable picking up a perfectly finished guitar.
Alan

B.Snow wrote:
"Over the next 14 guitars I tried several other finishing methods from nitro to EM6000 (which is pretty dang good honestly).

Fast forward to year 3. I'm on guitar #16 and thinking of trying to French polish again. I really believe my patience in the process has grown since I've been building, and think it will yield a better FP."

Is it because after 3 years and 15 guitars you have realized there is no quick and easy way to a good finish .
I have settled on nitro for the most part, but still do a less than perfect F.P. occasionally. I am going to try a brush-on Endurovar finish on the next instrument to see if it is something I can use in the house during the winter months. (I only burn electrons in one small room of the shop when I am actually working in there).
I am sure there are people on this forum that can advise you on F.P. if you need a "refresher" on it and there is a lot of information on F.P. in the MIMF library which might be worth looking at.
Unlike the "French Intensive Method" of raised bed gardening I use the "Less Intensive Method' when it comes to French polishing. Some people do 3 sessions of 3 coats in a day. I rub on 1 coat - maybe - twice a day. It takes a long time for me to build much finish, but I have less chance of the previous coat being rubbed off by the newly applied coat. Some people get it done in a day, I can take a month or more (so there are much better people to follow). I do find F.P. to be less onerous in some ways - I can keep the rubber sealed up in a jar with a little bit of alcohol next to the shellac, and rub a coat on in a few minutes when I think about it.
Some people ( MIMF library) have sprayed the first coats of shellac, let it dry, and then French polished the final coats. I've never tried that, so can't offer any practical advice on that.
I think "Patience", as you mentioned, is needed for most of the finishing we do. With patience and practice I think you will perfect your polish.

What type of shellac were you all using, Traditional or something more high-tech?

I have tried regular once and U-beaut from Australia that LMI used to carry, once. It seemed like it was harder then the regular shellac. Both done on cedar soundboards and it was still very easy to dent the soundboard with your fingernail. However, on the hard rosewood it's great. Is it sufficient for spruce?

I assume the Royal Lac that they now carry is similar, or just easier to get because it's from California.

Pat

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Pat

Clay, I believe, but do not know, that letting a coat or 2 dry everyday is better than doing too many in a day.
DAMHIKT.
Anyway, I have a flat spot on my forehead from beating my head against the wall with finishing.
Good luck on your FP, Snow.
Alan

This is a problem that dogged me a lot while I was French Polishing. I am just not sure I ever developed the consistent technique needed to apply a "net deposit" of finish. And in the traditional method, there are times when you really do want to remove (or at least soften and move around) finish, so getting a net deposit to happen, versus the opposite, was not easy for me.

I think I am better at finishes that require painting skill. In other words, whatever is underneath, I can spread a layer of finish, let the solvent go away, and leave material behind. Then I can sand to smooth it out, and apply more, as needed, then buff to a shine. But rubbing it on in such a way that puts more finish on top, instead of removing it? I just didn't feel like I consistently did it well.

I have FP'd two with Royal Lac and am happy with the results. I've used Timbermate and Crystalac for the fillers. And yes, like others, I've used a wide range of fillers and finishes. I am not interested in a perfectly flat super shiny finish but I'm very happy with the results I'm getting with the Royal Lac. I plan to keep using it. This one was filled with Crystalac.

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Steve Smith
"Music is what feelings sound like"

I do FP sessions every 90 minutes as many as I can get done in a day usually over a week period. I just finished one with Royal Lac and while I like it I am not certain it's any better then regular shellac. The few I did before that I used Button Shellac and didn't bother to remove the wax. Any shellac finish is going to be easily dented with a finger nail. That's why I like it so much

IMHO it's the most transparent finish for tone but you have to realize that it's not as protective as even nitro is. If I am making a guitar for someone who has such concerns they I use Nitro.

Here is a presentation I gave on my methods some years back. https://howardguitars.blogspot.com/2015/09/french-polish-finishing-traditional-way.html

I do things differently, I do as I was taught hand to hand by old guys when I was young.

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Brian

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

https://www.howardguitarsdelaware.com/

There is a cure time with FP, just like other finishes, but from what I understand it is applied nearly dry as you build the finish, so much so that you can hear it squeaking. This is a lot different than wiping on shellac, and much more labor intensive. I've SEEN it done, but man. … just haven't put in the time to get good at it.

Don, pore filling is DEF a huge part of how the overall finish looks! I have tried CA before. I think I used 2p10 med. and honestly it worked pretty darn well. Its wicked stinky and you can glue yourself to your work pretty easily though haha. The last few I've done is with epoxy, and it works well. The issue for me is definitely operator failure.

I'll definitely check this out later this evening

Brian, amazing amazing video.
Going to watch it again, mainly for your product recommendations.
One question, maybe I missed it, but what is the outer cotton on the mouse?
Is it jersey, or a woven type?
Anyway, thank you so much!!
Alan

FWIW, the methods in the O’Brien and Tom Bills videos are quite different. I’ve watched both. Robbie shows how to build a finish quickly, it’s the method I believe he uses in his build a guitar in a week courses. Tom’s approach is much different. I’m sure you recall, but putting a tiny drop of shellac off your finger to load the pad is what you do in Tom’s course.


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I'm planning on doing a write up in the near future about my finishing process with oil varnish. I outsourced my finish work for years to Joe White who did an incredibly job with polyester. With Joe White currently not doing any finish work, I had to find alternatives -- none of which worked out for me and nearly destroyed my business -- 2019 was probably the worst year of my entire life !!!

I'm incredibly picky and OCD. More and more, I have been thinking about my finish and tone has become more of a consideration. Even with a thin poly finish that Joe did (3-5 mils), my guitars always came back sounding less "alive". In the past few years, I French polished a couple tops for clients at their request and these guitars lost none of their tone during the finish process. The resulting sound was truly exceptional. My guitars are generally pretty good and on par with the best builders out there (think Somogyi, Sheppard, Kostal, Walker, Claxton, etc ... ) Well, these FP guitars would give any guitar a run for their money and beat out most. I was duly impressed but FP is just not a suitable finish for most clients.

Long story short, I've just recently settled on oil varnish (Murdoch Uralkyd 500) for a number of reasons and the tone is equal to French Polish. Durability is on par with nitrocellulose lacquer. It is bar none, the best looking finish in the world - I don't think there is much debating that. No problems with cold checking. Unfortunately, it is very challenging to apply and can have issues drying over certain woods (solutions for this issue but they require care and effort). It is also time consuming to apply and each finish layer must be scuffed to give the mechanical adhesion necessary to build the finish properly. It's not easily repaired but that can be said for many finishes. Also, certain oil varnish brands can be quite amber which I don't like. Over spruce, even the lightest hued varnish can be a bit dark. The solution is to apply a thin finish - but it will still have a subtle amber tint. IMO, this is the only real negative to the finish in terms of aesthetics. Lastly, I think it requires a rotisserie setup if you really want a quality finish.

But again, the finish is just extraordinarily beautiful. Take a piece of Rosewood and sand it to a mirror shine with ultra fine grit paper. Then heavily apply some boiled linseed oil so that you have a thick coating over it. Those first few minute before the oil soaks in and darkens the wood is basically the look that oil varnish will give you. You have a natural warmth and glow to the wood as well as incredible clarity -- it is a dazzling finish and also has a wonderful feel - so necks feel great. But again, it is a challenging finish to apply.

Personally, I'd advise against FP because it is just so delicate. I've heard some good things about Endurovar and a few of the waterbased products but despite getting a nice gloss, they've always looked very plasticky to me and the wood just looks a bit lifeless even with epoxy as a sealer. Nitro lacquer looks great but long term it's crap and the chemicals are nasty. Polyester and urethanes are great but the chemicals are dangerous. If you're setup for them like Brian - then it's a different matter but many of us don't have shops setup to deal with spraying dangerous stuff. This is why I've ended up with the oil varnish and while it has a learning curve, I do believe it is a great finish that can be applied safely and is quite marketable and applicable for the ultra high-end guitar market.

Just another option for you all to consider.

I can't wait to read it, Simon. And sorry to hear about such a crummy year!

I'm looking forward to your oil varnish write up, Simon. It is not possible to have too many arrows in the quiver when finishing is the question. However, I have to respectfully disagree with the central premise of your comments: French polish is not durable. Many times I have opined on the OLF that some aspects of shellac manufacturing or polish formulation have been lost. All one has to do is look at guitars from the late 19th to early 20th centuries to see how well shellac can perform. Even high volume shops like Lyon and Healy pushed out impressive numbers of guitars with shellac finishes that still look great today. The same holds true for luthier-built guitars I have inspected from this era as well.
Let's agree that any thin coating on the soundboard will be prone to nicks and dings. At 2-3 mils nitro, shellac, or oil varnish will not protect the softwood in any appreciable degree.
Let's also look at the evolutionary biology side of lac. Thousands of years of evolution have produced a substance who's sole purpose is to stick to wood in a hot, damp tropical climate. Kind of analogous to a hot, sweaty guitar player, no?
Lets's look at the applicability of lac for the hand builder. No special equipment is required. Dust, what dust? Unmatched repairability. No toxic fumes. No buffing arbor or compounds. Pretty much undisputed as the "best sounding" finish. "Best sounding" in quotes since the finish has no sound properties in and of itself.
It is true that the learning curve for the "feel" of FP is steep. But once mastered, I doubt whether any other finishing method is faster. At least for me this is the case.
At the present time my FP research is focusing on button lac, since it is clearly processed with heat. I happened across a document online called a "Commerce Report" from the US Dept of Commerce dated 6/12/1920. Part of the report documented lac culture and refinement into shellac in India at that time. There was no difference between shellac and button lac in terms of the initial refining process. Both were melted in cotton bags by an open fire. Shellac was melted onto a rotating cylinder filled with hot water and then peeled off while still molten and stretched by hand into thin sheets. This is the "handmade shellac" of today. I do not know of any sources for handmade shellac in small quantities. Button lac was melted in the same way and drops were formed on a metal sheet in the form we are familiar with today. Other odd bits of info in this publication mentioned is sometimes incorporating "orpiment" (trisulphate arsenic) or rosin into the molten shellac. The rosin was used to lower the melting point but possibly the addition of terpene compounds had some other effect? Orpiment was likely used to make the shellac more golden and transparent but maybe arsenic compounds altered the chemical properties of shellac as well? I am not advocating using either of these methods, especially orpiment (which is extremely toxic). Any chemists on OLF?
Last summer I mixed up some button lac and French polished a couple of plywood test panels. One was straight with the wax included and the other was dewaxed by passing through a coffee filter. After about a month of curing, I set both panels on my front porch steps on a hot, July day in the blazing sun. I puddled water on both panels to maximum and let the water evaporate. When fully dry, there was no damage to either panel other than a small amount of etching at the edges of the water drops. This etching was easily removed with a little polishing compound. On this limited test, there was no difference between waxy and dewaxed polish. I did not make a test panel with nitro but I doubt whether it would have held up as well. My guess is oil varnish would have held up, but the difference between an interior and exterior oil varnish might be the determining factor. I have no intention of working with oil varnish so there was no reason for me to make a test panel with varnish. Ditto nitro. My nitro days are a distant (bad) memory.
Dewaxed blonde shellac holds well on the soundboard of guitars but not so much on back, sides and neck. The lighter color of dewaxed is certainly easier to use on the soundboard. One could use button lac on the soundboard and this was probably usual practice back in the day. I have not seen the shortcomings of blonde on a soundboard and can clearly see its advantages.
Over the years I have tried incorporating various resins and gums into polish. Sandarac shows some promise, although I haven't noticed any appreciable positive effects. Mastic, at least in my experience, was not a positive addition. It softened the film and made it easy to mar with a fingernail.
I am hoping others will take up the shellac mantle and share results here. IMO, shellac is the perfect finish for acoustic guitars and the way we, as small builders, tend to make them.

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Stay with the happy people.
--Reynolds Large

I too would like to see your oil varnish schedule Simon. I have used oil varnish on a few instruments. It was a Sherwin Williams product that I used right out of the can. It made for a very good looking finish that was easy to apply but I didn't think it was any stronger or more protective then shellac. Bruce Sexaur was kind enough to send me his varnish schedule, and will to anyone who asks btw, and he uses an Ace Hardware product but mixes it down with acetone and maybe something else I cannot remember at the moment. His process is a bit more labor intensive but yields great results. Oil varnish has a great look.

After french polishing my first 6 or 7 builds and developing my skill level (did all the online research) I developed a friendship with Brian Burns the Northern Calif luthier. The most time consuming part of FP is being patient enough to apply enough coats to get the required film build. Brian suggested that I try mixing my 2 lb cut shellac with two parts acetone and padding it on quite freely. Here is a link to a thread in another forum where Brian's method is discussed and it has a bit more information:

http://www.acousticguitarconstructionfo ... 3&start=10

Needless to say, I wasn't aware of what an "azeotrope" was but the methodology suggested by Brian works quite well. You can get a substantial film build in just a few hours work. Let the solvents flash off for a day or two and you can then go back to the traditional method for final levelling and gloss attainment. It also makes it a lot easier to get the film build in the tight corners that traditional padding makes so difficult. YMMV

Cheers,
Peter

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Peter

Hi Tom,
I probably still disagree with you but let me clarify for others so they don't get the wrong impression -- French Polish is a wonderful finish and a worthy finish for guitars, no doubt. And you are absolutely right - repairability, along with nitro, it's the best out there. Regarding tone, it is THE finish to aspire too.

The pros and cons of finish types is in matters of degree -- how much protection does a finish afford and how durable is it to chemicals, sweat, and physical abuse and how easy it is to make repairs. All finish types have their strengths and weaknesses.

I do a French Polish as good as anybody and better than most -- out the door, it looks as flawless as anything I've ever seen. I also take the longer route - none of the super fast build methods. From what I understand, the fast build methods can be a bit softer in the short-term. In the long run, I don't think there is a better finish than French Polish. It is super repairable and becomes quite durable. The first few years of my learning to build -- and all I ever did was French Polish. If you use Everclear as your solvent - it is wonderfully non-toxic compared to just about everything else.

I also absolutely agree that a very thin film doesn't offer much protection but that is the price you pay for maximizing tone. That said, I do find French Polish tends to not stand up very well for the steel string crowd. Even with careful handling, my clients still have very small battle scars that wouldn't be there with most other finish types. Some clients are okay with this but most will not be. My opinion is that most players will want a finish that is a bit more durable; hence, why I chose to continue using a polyester finish for my tops even when I could have French Polished the tops all along.

The advantage for me with the oil varnish is that you get all of the tone of French Polish but you also get a more durable top. In fact, I might even like the sound of the oil varnish a bit more than French Polish - but that's hard to tell and they are extremely close. Every client that I've FP'd for has expressed to me how surprised they were about it's durability - they were not expecting it to be quite so delicate. I was talking to one of my customers the other day and he was saying how he doesn't even know how any of the marks on the soundboard got there because he is ultra careful with never touching the top. If he had oil varnish, the top would likely be flaw free. I think the general consensus from most luthiers is that French Polish just isn't as durable as other finishes - at least, in the first decade of it's life. The oil varnish isn't as durable as polyester but it's better than French Polish and close to lacquer. It is still a "delicate" finish but I do feel it's a more "approachable" finish for the steel string crowd.

I recently saw back a well used guitar that I sprayed with PC royal-Lac, which supposedly has additives to overcome the lack of water/sweat/alcohol that regular FP users comment on. It still looked great.

However, I was completely unable to either pad it on or FP, but I know of at least one person who is able at least to FPmthe tops with it.

Any of you regular FP folks tried it?

Regarding my oil varnish schedule, I'll give a few bits of information - although, I'm still working some stuff out.


1) West Systems epoxy porefill (207 Clear Hardener). Thicken the epoxy to the consistency of mayo with silica. Apply everywhere with a squeegee or old credit card. Leave nothing but a film behind if possible. Repeat.

It is also important to do this on the top as well. Due to the consistency of the epoxy, almost no material soaks into the grain. It just rests right on the surface. This drastically reduces the yellowing effect of the oil varnish !!! It also means that the finish isn't soaking into the wood - instead it's getting bonded right on the surface which is exactly what you want. If you sand with fine grit paper, you will be through the epoxy layer and down to bare wood in just a few swipes. Again, that's exactly what you want.

2) Shellac sealcoat. I mix up fresh dewaxed super blonde in a 2lb cut. You have to use dewaxed or the oil varnish won't adhere. I rub on two sealcoats over anything that the oil varnish might have trouble with (Ebony and Rosewoods) and just 1 coat for everything else.

3) Apply 1st coat of Murdoch Uralkyd 500 full-strength without scuffing the shellac. I let this dry for several days just to make sure it has completely dried. It should be fully dry in 24 hours but it may struggle in some places. The additional drying time helps with this as you never want to apply more oil varnish over a coat that is still soft/gummy.


4). Apply 2-3 more coats for the top and 4 to 5 more coats everywhere else. You wait about 1 day between coats. I scuff sand with Super Assilex k-1200. -- equivalent to P1200 or 600 grit paper. It is essential that the entire surface is completely deglossed. Shiny spots in pores is okay tho'. By the 2nd or 3rd coat (your penultimate coat), you will want to level sand really well. Once you don't have any more pores and the surface is completely flat, you can do 2 more coats.


5) My struggle with oil varnish is that it wants to run/drip everywhere. So I built a rotisserie setup that spins the piece. This results is a glass smooth surface with very little leveling needed.


6). After the last coat, hang it up for about 3 weeks and then level sand and buff. The biggest issue with oil varnish is witness lines. You can wet sand the last coat but I'd advise never wet sanding any other coat. This is where the Eagle Abrasive product line comes in. They have amazing products that allow you to dry sand with ease. They work insanely good but are quite expensive. I'm still figuring out which grits to use but I've almost got that figured out.

The advantage of dry sanding is that you can see what you're doing. Ideally, you level sand with a super fine grit and then go straight to buffing so that you don't burn through one layer into the next. If so, that's how you get a witness line. The rotisserie helps immensely with laying down a flat, smooth finish especially on the neck. It also prevents the finish from pooling around edges, etc ... This means less sanding and less work needed to get the finish where you want it.

Once you are at the stage where everything is perfectly flat and level -- then you want to do 2 more coats. Depending on how well you pore fill and how everything goes, you can be at this stage in as soon as 1 coat but usually it's 2 to 3 coats (for the back at least). As mentioned, I aim for 3 coats on the top and 4 everywhere else.

I'm using the Murdoch Uralkyd 500 product. It dries quite hard and is less amber than most other products. It smells great and is pleasant to use - no harmful fumes. For the rotisserie setup, I'm using a 3phase conveyor motor hooked up to a VFD. This turns a hollow aluminum pipe that I can place my "paint sticks" in from either side. Thus I can do 2 parts at once. I'll take pictures of all this once I sit down to do a full write up.

I'm currently using foam brushes to apply. You apply a coat and then throw away. Using bristle brushes is challenging and these foam brushes work great and you don't have any of the issues that plague brush users.


For me, the big keys to success with the oil varnish are:

1) The Rotisserie Setup
2) The dry abrasives from Kovax/Eagle Abrasive
3) Foam brush application
4) Epoxy pore fill and shellac sealcoats


One last thing, thanks to Collings -- oil varnish finishes are very marketable.

Sorry for the rambling layout -- within a couple months, I'll do a writeup that explains my process much better and with photos. If anyone wants to speak with me before then, please don't hesitate to contact me -- contact information is available at my website (fay guitars)

Are you hand sanding or power sanding?