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If I am going to use shellac as the exclusive finish on a build, does it need to be dewaxed?

Why or why not?

Please share experience if you have any with using unrefined shellac.

Thanks,

Dave

My understanding from reading Alan Carruth's posts, is that if you dissolve shellac with wax in it, using the T-bag method, it, the wax will remain in the bag. The method involves hanging a T-shirt bag of shellac tied with a string in the alcohol, near the top of the liquid, but submerged. The shellac, as it dissolves sinks to the bottom of the jar, creating a bit of current, which keeps the alcohol moving through the bag. After everything is dissolved, any impurities and wax stay in the T-shirt bag, and the resulting shellac solution is de-waxed.

There is no reason to use waxed shellac for finishing.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Some luthiers use the old button shellac which has wax in it with fine results. I just watched a video on it a few weeks ago but cannot find it now. I think they claim it's easier to apply with the FP method and doesn't really have any disadvantage in terms of hardness or water resistance but it has a bad reputation because you cannot mix it well with other finishes. De-waxed shellac has the reputation as being the ultimate sealer for example and can be topped with anything and will stick to anything but that is not necessarily the case if it has wax in it.

I've never tried it, just reporting what I learned a few weeks ago.

Maybe Brian Howard will pitch in here, I seem to remember he teaches FP and advocates the use of less unrefined shellac.
https://www.youtube.com/watch?v=aJ5Zmm9ZKvc

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I use button shellac almost exclusively for my FP finishes. It contains wax and I do not de-wax it. This is the same type of shellac that was used to finish gymnasium and ballroom floors prior to the invention of poly-urethanes in the 1950's. If it can stand up to that type of use it is plenty tough for guitars.

Here is a link to a video from my blog of a presentation I did on my FP process s few years ago. In it I talk about the advantages/disadvantages of waxed and de-waxed shellacs.
http://howardguitars.blogspot.com/2015/ ... l-way.html

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Brian

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

https://www.howardguitarsdelaware.com/

Ah yes... That was the video I was talking about.

Thanks for chiming in Brian. I'm really interested in the waxes effect on shellac. Leaving it in seems like it's gathered more advocates in recent years.
Do you see a big difference in durability when wax is left in?
Is it possible wax was left in for gym floors because they needed a ton of it and getting it out added to the cost?

Thanks for the responses guys.
I can't wait to try it out.

One of the harder things about life is that we just plain flat out don't know what we don't know.

I've been at this for years and just accepted that blonde shellac flakes were the only thing out there.
Tried dewaxing button lac a few times without ANY SUCCESS and am happy to have a new trick up my sleeve.

Dave

I'm just about to try oil varnish for the very first time. My search is never ending for the perfect finish.

Thanks Brian, never heard the benefits of non de-waxed shellac before. Sounds promising!

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Pat

Dave here's some button lac I'm in the middle of dewaxing.
After the buttons dissolved I set the jar in a warm spot in the house, right behind a window with the sun shinning in on it in my case. After about 3 or 4hrs the wax settled out and you can see the wax gathered on the bottom of the jar. Next I'll decant this through a filter to remove the rest.

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Jim Watts
http://jameswattsguitars.com

Thanks Brian,

I really like using shellac. It was always a mystery why someone would dewax it and then use olive oil to make it slippery. I have been using dewaxed flakes, with success. I am going to try the buttons. I think shellac is the best finish for bringing out the 3D appearance of wood grain. Regarding the labor (more to FP), I see it as a Zen exercise.

Regards.
GS

The wax was left in for durability, but it's not just the wax increasing the durability. Button lac is polymerized some in the process that makes the buttons from the seedlac making it a better linked film chain than flaked or any other type of shellac. The wax allows the shellac to take more abuse and not wear away as fast but it's nemesis is water.....to further protect the shellac coating a paste wax is generally used and guess what most high quality furniture paste waxes are made from......yep the wax they take out when they de-wax shellac. Hmmmm. and when you apply this over a shellac finish that still has it's natural wax in it the two bond at a molecular level giving a bonded wear absorbing layer to protect the finish underneath.

Them old timers might not have known the science behind it but they new what worked.

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Brian

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

https://www.howardguitarsdelaware.com/

The only reason for using de-waxed is if you intend to use your shellac as a seal coat under some other kind of finish, like nitro. If you're using shellac exlusively, waxed is fine.

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I'd like to be able to prove, just for once, that money wouldn't make me happy...

How could something vulnerable to water be considered durable? Humans are mostly made of water, and a lot of it comes out when playing hard in hot weather... and what if it rains?

I use blond flakes without oil. Takes a little more arm power due to the higher friction, but works just fine. Completely waterproof. I've tried putting a pool of water on it and letting it dry out, with no ill effect. But it does indeed wear through after some years of playing.

Or does the additional wax coat make it waterproof? But that doesn't make any sense if it's the same kind of wax that's in the shellac to begin with, and that's what makes it vulnerable in the first place...

I usually try to keep my guitar out of the rain.

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Steve Smith
"Music is what feelings sound like"

I have a tall case clock made in England in the 1740's in my living room with its original FP finish intact...... Hows that for durable? was even shipped across the ocean when that was a real hard trip. Meanwhile lacquer finishes done less than 50 years ago are checking and flaking and peeling.

Whiled I cannot say for sure whether the shellac has the wax in it or not I suspect it does.



The wax put on over top of the finish forms a protective wear layer. It takes the scuffs and scratches while protecting the actual finish film beneath. When dealing with wood, nothing is waterproof. Not even marine epoxies.....Wood was made with sunlight and water and it never forgets this and will always react to these things. That is why wood still responds to RH by expanding/contracting no matter if it is finished or not.

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Brian

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

https://www.howardguitarsdelaware.com/

This is a great topic and very worthy of discussion.
I raised this question back in 2007 and was mostly shot down for daring to challenge one of the Luthier Truths about dewaxing shellac by letting it decant.
http://luthiersforum.com/forum/viewtopic.php?f=10102&t=14830
I have always been impressed with the finishes on old Martins, Lyon & Healys, and other instruments at the turn of the 20th century. Many of these instruments have led a hard life with lots of playing and then possibly stashed in an attic somewhere for many years. The finish that remains looks fantastic. By most accounts this finish is a shellac of some sort, possibly with additional gums added. I think it is a stretch to think that a busy shop like Lyon & Healy would wait for shellac wax to settle in solution and then discard 10-20% of the dissolved mixture in order to get wax-free shellac.
I think it is safe to say that most knowledge of lac and shellac has been lost with the advent of cellulose and other modern coatings. The old timers who worked with this stuff are long gone. Those of us who see the advantages of lac are now tasked with rediscovering how to work with it.
There really isn't a more perfect finishing material than lac for small production, IMO. Quick drying, low toxicity, no special equipment or spray rooms required, and the best repair-ability of any finish out there. Once the learning curve of application is mastered the actual time spent from start to finish is probably less than most other instrument finishes, with the possible exception of UV-cured poly. Upon inspection of the finish on the early guitars previously mentioned durability is not an issue. There is a missing link somewhere, however. I have yet to find a lac product that rivals this finish and I have tried every grade of lac and shellac from stick lac through super blonde.
Like most agricultural products, lac has undoubtedly undergone changes in cultivation and harvesting since the early days of the 20th century. It is entirely possible that the lac we have these days is not our great grandfathers' lac. It has certainly undergone changes in the way it is processed. From what I can gather there are a two ways of processing lac: solvent and heating. Again, my knowledge of lac processing is sketchy but I believe blonde shellacs are solvent extracted. Real button lac, which looks like melted blobs, is heat processed. I have seen pics (and a video somewhere) of workers melting lac in cloth bags by a fire and twisting the bag to extrude the shellac. While still hot the workers stretch the molten shellac into large sheets which are then cooled and broken up into flakes. Chemistry is not my strong suit but it would seem to me that heating the raw lac might change something about its compostion, possibly driving off volatiles or polymerizing the lac somewhat.
To close this long ramble I will post a quote from a book about finishing published in the 1920s as food for thought:
The Chemistry of Paints, Pigments and Varnishes by J. Gauld Bearn, copyright 1924:
"As a rule Button Lac is somewhat harder than ordinary orange shellac, owing to the small percentage of shellac wax that it contains"

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Stay with the happy people.
--Reynolds Large

Impressive, but not necessarily applicable since a clock is generally never in contact with human skin for any significant amount of time, or taken outdoors except when moving. Though I suppose in 275 years of moving, it probably has been done in the rain more than once, so perhaps it is resistant enough.

And certainly no finish will keep water out forever. I just don't want to have to keep a towel between my arm and the guitar, or panic and search for droplets every time it gets a little spritz of water on it.

I really appreciate that I have a place to discuss and learn about shellac. I use it quite a bit, and really enjoy it. When I try to discuss it with my wife, kids, or work colleagues, they run away. Thanks gang.
GS

I haven't had a problem with arm marks, any more than any other finish. I think if the user cleans the instrument when it gets sweaty, and as Brian recommended wax when doing a string change there will be no problem. I have had a few 1900 - 1920 Regals and Washburns, they were shellac finished and there was no arm wear on the front, and I am sure they went decades without being waxed.
GS

There is certainly guesswork at play when admiring an old finish. Shellac just seems to beg for additives, and finishers in the past were no dummies. I have five old books from secondhand bookstores about finishing that raise more questions than they answer. A few of them talk about mixtures (in a jar before application) of nitrocellulose lacquer and shellac. My experience with the durability of modern pure shellac-only finishes suggests to me that those 100 year old guitars have more on them than pure shellac, whether it is a plasticizer or nitro I wouldn't want to guess.
In a book (on writing) by a Zissner, of the Zissner shellac company, he describes how the company reputation was built on the purity and simplicity of the product. Meaning that other old shellacs contained contaminants and innapropriate additives.
I love shellac but I am inclined to follow layers of dewaxed shellac with a thin coat of nitro lacquer for scratch and water resistance on a guitar.

Mr. Howard is from a woodworking family, he learned the techniques of the old timers from them.

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A man hears what he wants to hear, and disreguards the rest. Paul Simon