Sealers and grounds

[JohnCockburn]

cremonese didn't use shellac or seed lac til about 1780 and it was then considered the death of the classical varnish tonally, theres some evidence they didn't even have alcohol strong enough to dissolve seed lac till after 1700, if you want to ignore the scientific evidence that has been presented on this forum about cremonese varnish and go ahead and use shellac just don't ask me to listen to your violins i hate the hard screechy effect of shellac zulu out

Please, can you drop this ludicrous affectation? Cockburn out.

[stradofear]

Can someone sitting on a pile of STRAD mags come up with the article? It was impressively-well researched.

[Michael_Molnar]

In his new book, Stradivari, Stewart Pollens discusses the inventory of Meschieri, a neighbor and contemporary of Stradivari. Meschieri was a chemist and pharmacist who stocked shellac among other useful varnish-making ingredients according to Pollens. The account is a good read and very compelling.

Stay tuned.

Mike

[fiddlecollector]

I have also heard that shellac varnish came very late (around 1700). But I would love to learn more about earlier use of shellac, and if possibly I had it wrong.

I dont know exactly when shellac was first used as varnish in Europe but lac dye was used centuries before ,in the 16th century shellac was imported by the Spanish from India for sealing wax compositions(cant see why they didnt find another use for it) and im sure Parker? and ? (cant remember the names) in their English book from the 17th century mentions the ready use of shellac for use on furmiture trying to recreate Chinese lacquers.

[Johnmasters]

Maybe it is a mistake to ask "what is the sealer". Or ground. Even modern woodworkers say "seal, fill, seal" and I have to assume that this goes back a few years. You also have several opportunities to use a stain here.

I also think it is a mistake to think only in terms of chemistry... Physical behavior, or a combination of behaviors might be worth considering.

[Geoff-UK]

Oil on wood is generally not thought to be good acoustically.

I recall someone telling me about mixing shellac with a drying oil. I can see the possibility if you were to make an emulsion with water, shellac, borax and oil. But I suspec there might be other ways to making the mix without using a base.

Oded

I like the finish one gets when you do wipe oil varnish off of a shellac base using alch - I've been tempted to do it deliberately. I think somehow some of the oil gets mixed in with the re-dissolving shellac and you end up with an interesting coat.

I mostly seal up with Pale shellac and sandarac in alch.

Shellac and Borax in boiled in water is an interesting sealer - seemed to work very well on Poplar.

Geoff

[Darren Molnar]

Thanks for the heads up Don.

[Oded Kishony]

Testing done on the decorated Strads showed that the black part of the decoration was made using shellac and lampblack. So not only was shellac available, Strad actually used it on his early instruments.

It's true that shellac can increase stiffness, but it does not follow that instruments sealed or even varnished with shellac are necessarily 'screechy'.

Oded

[CT Dolan]

Michael, is it possible that the killer ground I saw on a Pietro Guarneri (of Mantua) was actually just simple shellac??? If so, why the heck doesn't the stuff we have around in our day seem capable of the same (method of application aside)? My goodness, the optical effect and tremendous depth of whatever made up the Guarneri's ground coat was stunning, and while I must admit the stuff did look like shellac, in one sense, I cannot for the life of me imagine getting quite as dramatic a result with shellac alone. I guess what I am trying to say is, it has been one thing for me to look at a violin in a book and think "shellac" (the Lord Wilton, in particular, had this effect on me); but it was quite another experience to see (and hold) the Pietro Guarneri in the flesh (and especially to see the gound coat in full sun). It had a quality I find very difficult to describe, but I am quite certain you know exactly what I'm talking about. :-)

Anyway, I think shellac has a lot going for it, not the least of which is the practicality of the material (for one will usually find the answer to life's most vexing questions a great deal more close than we'd otherwise like to think...sometimes we simply complicate matters for the sake of sport). I'm just not sure how to make shellac work, to such an effect. But, I guess that's why we're all here. :-/

[Oded Kishony]

I know that oil changes it's index of refraction over time, is there any evidence that shellac changes in some similar way?

~OK

[stradofear]

Pietro Guarneri (of Mantua)

Yeah, of everyone his varnish is my favorite. One thing about it is that the "ground" is very thick, most of the varnishing job, and the color, if it still remains (which is often just a little bit in low spots) is a very thin wash of red. I love the look. You'd think someone would peel a speck of that ground off and find out what it is, for all of us.

I think there's more to it than just the material, as John Masters also mentioned.

[joerobson]

CT,

"It had a quality I find very difficult to describe,"

three dimensional

a fiery internal reflection

it's lit up, but not shiny

I can see EVERY detail in the wood

it sparkles, but it doesn't shine

I can see INTO the wood

and my favorite.....

there is light coming up from inside the wood so those little brown flecks seem to float on light

on we go,

Joe

[David Tseng]

Shellac is in! I've never used that stuff in my life. Now I've got to learn to use it. What a transformative learning.

[stradofear]

One of my young customers nailed it when I showed her a Strad. She immediately said "It looks like a holograph!"

[CT Dolan]

Yeah, of everyone his varnish is my favorite. One thing about it is that the "ground" is very thick, most of the varnishing job, and the color, if it still remains (which is often just a little bit in low spots) is a very thin wash of red. I love the look.

Yep, that's pretty much what it was. Joe, every one of your descriptions is pretty apt as well. In a way, the ground coat kind of reminded me of a "cat's eye" stone, the depth and manner in which it scintillated. The effect was unforgettable.

Holograph...good one.

[robedney]

cremonese didn't use shellac or seed lac til about 1780 and it was then considered the death of the classical varnish tonally, theres some evidence they didn't even have alcohol strong enough to dissolve seed lac till after 1700, if you want to ignore the scientific evidence that has been presented on this forum about cremonese varnish and go ahead and use shellac just don't ask me to listen to your violins i hate the hard screechy effect of shellac zulu out

Hmmmmmm.

I may not agree with everyone here, but I have a great deal of respect for people who are very good at what they do and take the time to share their knowledge. Referring to their work -- widely acknowledged to be excellent -- as screechy is perhaps not the best way to encourage participation.

[robedney]

I have read evidence to the contrary of what you are saying, and there was an article on the subject some years ago in STRAD magazine. According to the article, shellac's history on furniture dates back to the mid-1600s. [edited response, so poor victim poster won't fear me and go dark on us forever because of unfriendly Maestronet people abusing him . . ]

Hadn't caught up to this response before posting mine. If you're editing was due to the thread "Do you not post here because..." the point has been missed. Zulu rather set himself up there for a civil thrashing. Nonetheless, you're restraint has been noted in the Maestronet family Bible and assures you of absolution from at least one venial sin. Further absolution is available, PayPal accepted.

[Oded Kishony]

To what extent is the holographic effect dependent on a high IR of the sealer?

Can the holographic effect occur without the sealer penetrating the wood?

Oded

[stradofear]

I can't see pretty wood without the sealer, but I also doubt I'd see pretty wood without the wood.

[Michael_Molnar]

There are many ground coatings that can bring out the "holographic" effect of curly maple. I had success with Canadian Balsam. I got that idea from my lens making days. Joe Robson uses a similar process, I think. Having said that, I find shellac easy, fast, and clean.

Let me try to explain the optical effects in a simple way: Think of a glass bottom boat. The reason you can see better through the window down into the depths of water is that the surface ripples (tiny waves) are eliminated. The ripples on the top of the water distort the view of the water bottom AND shine (cause glare) light from the sky/sun. The smooth glass removes this distortion and glare that masks the light from deeper down.

In the case of wood, the "ripples" are not due to how well or poorly you scraped or polished the wood. The ripples are now due to the orientations of the tops of wood cells. When a clear coating matching the optical characteristics of the wood cells AND when the coating has a smooth top surface like a window pane, you duplicated the glass bottom boat: Light is not distorted and reflected from the top wood cells causing "glare" that masks the reflections from the wood cells deeper down.

The beautiful "holographic" effect of maple is due to the grouping of cells in the curl - a spiral twisting of the wood.

Hope that made things clearer. (PUN)

Stay tuned.

Mike

[Doug Rice]

Everyone,

This thread is wonderful. Thank you all.

I am currently using varnish with pumice. It seems OK, but nothing special.

I tried a thin coat of polymerized tung oil - the violin seemed fine, but I moved on.

Oded's madder tincture and shellac sounds promising. I will give it a try.

I wish I had more to contribute.

Doug

[Janito]

Others

(i) Almond oil (v little) + silica powder paste

(ii) rosin oil (v little) +/- mineral powder

----------------

One day one may see a list inside a new violin similar to that on tomato cans:

- Portion size - full, 7/8, half etc

- Caloric content or weight

- Composition: wood

- Composition: varnish - (most abundant ingredients first)

and perhaps

- Water content

- hot air

[Craig Tucker]

Shellac is in! I've never used that stuff in my life. Now I've got to learn to use it. What a transformative learning.

- That's right!,

We tried to tell you eons ago, but would you listen?

The point is, shellac is something that works, period.

There is really nothing special about shellac, other than the fact that it is simple, direct, and can be made to work. I believe that it works particularly well under oil varnish, and I will second the idea that it also works well with pumice dissolved in it. I'm not sure yet if it works better that way or not. But it makes for an interesting ground. (when I tried mixing fine ground pumice in shellac, it seemed to add, a bit of surface "tooth", and an interesting sort of "reflective" quality to the ground after the varnish was on - I don't know for sure, I have to try it some more to be sure I really like it.)

For anyone who actually does bother to make violins today, something must be used, and until the "magic formula of Cremona" is recreated or rediscovered, shellac does a fine job.

I believe that a number of things must also work just as well, since tone is a complex matter and not entirely dependent on a (magic) thin coat of finish (some of it has to do with construction, after all) and as far as recreating the old Cremonese magic finish - it is as Joe says...

On we go!

P.S. - to save you some time experimenting, the stuff in the can works fine (I have used both Bullseye shellacs, amber and clear) but high quality flakes just seem to work better - mixed, as I have said here already, with quite a bit more alcohol than is recommended - unless you want a thick ground.

[Craig Tucker]

P.S. - to save you some time experimenting...

I would love to hear from anyone who already uses shellac, how you use it, and if you mix anything with it when you use it.

Thanks,

Craig T

[Michael_Molnar]

Try garnet shellac too to enhance the wood figure. It's a matter of personal taste, nevertheless.

I will try Oded's tincture soon

Stay tuned.

Mike

PS: Doug, I agree that this is a fascinating thread. Thanks to all!