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On the old Bechstein video it looks like they are rubbing out a finish with pumice. How did they do the high polish before nitrocelluose lacquer was developed?

French polish. (Looks like an oxymoron!)

French polish was the standard for fine furniture, not just pianos. You can do high gloss NC, but most pianos today are polyester.

NC laquer is a rather new development when you consider that the Chinese were using and perfecting natural lacquers hundreds of years B.C.

A true French Polish was, and is, a technique for the finish on fine European furniture. It is shellac based, rather than lacquer or varnish. It has always been uncommon in the US and when the term is used, it simply means "buffing."

Varnish was, by far, the most common wood finish used in the USA. Lacquer was only used by the finest of cabinet makers, piano cabinetry included.

this piano is a 1908 Bechstein High gloss black I am wondering how they did that

I told you.

The last coat(s) are high gloss clear polish. If not when you clean the case the cloth get blackened.
Not sure if we see some fine sanding with pumice to obtain the mirror like surface below the last coats, or preparing the bottom coat once the grain is closed, or preparing a final buffing.

They could use a buffed quality of varnish, also. Black undercoats on German pianos often very resistive to solvents. I have find undercoats that looked more like skin glue than traditional pumice plus alcohol prep.

I am still unsure of the difference in terminology lacquer vs varnish.

Is one having direct gloss and the other need to be rubbed , or is one using solvents and the other a catalyse process, as oil based varnishes ?

Then PU is considered as laquer , in French, can be sprayed.
As are Akryl based products.

Varnish is said for soundboard traditional recipe as well as for shellack based products, for cellulose, poliurethan , etc... hence my confusion

Historically --

Varnish is a dissolved tree resin and the solvent would usually be linseed or tung oil.

Lacquer is a dissolved insect resin and the solvent would be Butyl Acetate + Xylene (Distilled from non-fermented source - Lacquer Thinner).

Shellac is a dissolved insect resin and the solvent would be Alcohol (Distilled from fermented source).

There are all sorts of variations and "recipes" and the ratio of resin/solvent creates different resultant products. Various oxides and dyes were often added for color.

Dupont Chemical, in the early 1920's created a resin from cotton, using various solvents, and that is the birth of Nitrocelluous Lacquer. It was developed to be sprayed on and quick drying finish for the auto industry. Depending on its chemical composition, it is, indeed "paint" in common usage.

Furniture lacquer is quite transparent with the stained wood being the primary color source. Paint has heavy coloration/pigment contained within the the suspension medium.

Of course, this is totally different than any of the modern synthetic finishes.

Hope this helps.

Thank you Marty, so Varnish (in English) will more likely be oil based products.

Lacquer was probably also other resins (the insect is only for Shellac if I understand well) in thinner

Chinese lack is done with a tree extract and pigments are added.

Cellulose and Nitro Cellulose have been used widely.

SO you say that the American makers where using oil based varnishes on piano cabinets (they can be brushed, then rub/polished) .

Possibly similar products where used on German pianos before 1930,

I'd like to know.. Those are often easier sanded than stripped, before black shellac is used.

Kamin,

Read both of my postings. Lacquer and Shellac both use insect resin and the difference is the solvent. The term "lacquer" is derived from the Lac bug which is common in China and India. Trees (conifers) are the source for the resin used in Varnish.

Varnish naturally dries to a high gloss and doesn't require buffing. That's why American furniture builders used it so often. "Hand rubbed" lacquer was used for "status" furniture such as pianos.

An early Bechstein would certainly have a French Polish. (Read my first entry) It would not be "Varnished."

From Dave Beningfield, a third generation fine furniture finisher:

Hi Dan,

As for your question regarding the time frame of when lacquers started being used on pianos, the answer may depend on the manufacturers. What I do know is that spray nitrocellulose lacquers started being used on some production furniture as early as 1900, and by the time my dad served his apprenticeship in 1930 it was in common use. Nitrocellulose lacquers chemically are related to film celluloid and cellophane. They are still in use now, and I believe Steinway still uses this lacquer. I'm pretty sure that after WW11 most production pianos were being sprayed.



http://www.wcbeningfield.com/index.htm

From John Albers, Chemical Engineer

"Nitrocellulose lacquer was first invented in 1921 by Edmund Flaherty while working for the DuPont Chemical Company. The rights to it were quickly bought by the Ford automotive company. When mixed with pigments, the nitrocellulose made an excellent quick-drying paint, speeding Ford's car production immensely."

Dave Beningfield appears correct as DuPont got into the nitrocellulose lacquer business in 1904 by acquisition:

http://www2.dupont.com/Phoenix_Heritage/en_US/1904_a_detail.html#timeline

Just in the interest of completeness, shellac can also be considered a form of varnish... a "spirit varnish."
https://en.wikipedia.org/wiki/Varnish

Also, here's something I learned about on this forum a while back. Today, we actually have water-based shellac. An example:
http://www.targetcoatings.com/shop/products/UltraSeal_WB_Shellac_Sealer_Amber-169-10.html

This is getting silly, but don't read into something which isn't stated.

The factory was purchased in 1904. Lacquers go back thousands of years. This is taken from DuPont's own history of the company:

"DuPont began producing nitrocellulose-based pyroxylin lacquers after acquiring the International Smokeless Powder and Solvents Company in 1905. The purchase of the Arlington Company ten years later [in 1915] deepened the company’s involvement. Although they were quick drying and widely used on brass fixtures, conventional lacquers were too brittle for more demanding uses. By the 1920s, however, the automotive industry had become a huge potential market. Although mass production [of automoboiles] had vastly increased output, because conventional paints took up to two weeks to dry, finishing remained a bottleneck. In 1920 chemists working with film at DuPont's Redpath Laboratory in Parlin, New Jersey, produced a thick pyroxylin lacquer which was quick drying but durable and that could be colored. DuPont marketed it under the name Viscolac® in 1921. Assisted by General Motors engineers, DuPont refined the product further and renamed it Duco. The success of Duco led to further experimentation with finishes and late in the 1920s, DuPont developed Dulux, an even more effective alkyd finish. Duco retained a niche market, however, and DuPont continued to produce it at Parlin until the late 1960s."
-------------
"DuPont has been using Dulux enamel in automotive coatings since 1926. Dulux actually owes its existence to a flaw in its more famous cousin, Duco. This nitrocellulose lacquer first brought color to automobiles when General Motors used it in 1923."

Ian - "Spirit varnish" is a solvent, similar to turpentine, and is not a finish coating. Like I said at the very first: "Historically." All of this is in response to the question of what came before Nitrocellulose Lacquer?

Now we have "water based" just about everything. What is now is very different than what was then.

Spirit varnish is resins dissolved in alcohol. When it is spread on a surface, the alcohol evaporates, leaving a coating of the resins. So it is indeed a finish coating. It was used for pianos before artificial lacquers and other modern finishes came into use. The other finishes that were used were oil varnishes, which took longer to dry, usually not drying completely. They were not used for furniture or pianos.

French polish is a method of applying spirit varnish.

Shellac is the last of the commercially used spirit varnishes.

A spirit varnish is most definitely a finish coating. For example, Behlen's Violin Varnish identifies itself, along with its vendors, as a spirit varnish. See http://www.stewmac.com/shop/Finishing_supplies/Finishes_and_solvents/Behlen_Violin_Varnish.html
Btw, they recommend thinning with Behkol Solvent. Behkol Solvent is a very high-grade denatured alcohol. http://www.stewmac.com/shopby/product/0774

Quoting the Wikipedia article:


Basically, you have oil varnishes and spirit varnishes (though there is often some overlap between the two). Oil varnishes react with the atmosphere and harden, while spirit varnishes, like shellac, evaporate their 'spirit' and leave a coating behind. Of course, oil varnishes are usually thinned with some solvent, so there would be some overlap. But speaking very generally, this is how they work. Of course, we can get into this subject a lot more deeply, like discussing short oil vs long oil varnishes, etc. But, that would be dragging us too far O.T.

These days, we say evaporative finishes and reactive finishes. There are a variety of reactions that can be used for reactive finishes.

Well, if you MUST drag us into the 21st century