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Pore filling


cbouts
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Perhaps varnish making was one of the activities which could be done without daylight.

Yes that may be, but you well know that some varnish process require long time, quite a few days.

It's not looking that way right now. It's even looking like the varnish of a single maker wasn't always the same. Perhaps some underlying processes were common and widespread, like combining a resin with a drying oil.

Yes that could be... but if so would be a false secret, no one specific recipe but a ingredients list that could change.

It seems that records are missing for many parts of the making process, not just varnish. I'd be hesitant, for instance, to say that the makers didn't do their own graduations or archings, just because we don't have records of the processes.

It is not true at all, arching and thickness was more easily intuitive, and sharing was not necessary. You can copy an old good classic violin easily. Instead you can not copy a good classic varnish.

(generic you)

A couple of theories are that the definition of "quality" changed, or that quicker or more efficient methods were embraced. Look at the switch to lacquers and urethanes, as an example.

I'm not trying to make a case for the makers doing all varnish steps themselves. It's just that I haven't seen a good case against it either.

I'm only conjecturing...

I apologize if I could seems rude or aggressive, that is due my insufficient acquaintance of English language

G.

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I'm only conjecturing...

I apologize if I could seems rude or aggressive, that is due my insufficient acquaintance of English language

G.

Hi David, Bill & Guiseppe,

"A Treatise of Japanning and Varnishing" 1668 recommends that you do not let your varnish rise over and endanger your "chimny and materials", nor should you strain varnish "by fire or candle light". "Fine-varnish will cost you 3 pennies an ounce at the colour-shops, which is too dear and therefore you should make your own". There are also instructions "To prepare ordinary rough-grained woods". In Paris, the famous Martin family began their varnish making workshops in the early C18th. So you could either buy, make or combine varnishes.

Melvin:

The "Treatise" also gives choice on "Lackers" that make silver look like gold and improve the colour of gold. I can only agree about the incredible diversity of violin finishes and I am absolutely confident that flame was frequently enhanced. There is a strange scarcity of information about this in old cabinet makers' texts and I only know of one early method which I will send to you, or post if anyone else is interested. In this thread, my thoughts have been restricted to to the finish on very early violins and I am still hoping that another experienced maker has been working along similar lines and/or has followed up on some of my suggestions and may feel able to collaborate.

Guiseppe:

Careful study of Baschenis reveals that he is quite capable of depicting clear varnish over wood, particularly on some of the plucked instruments. He treats the violins differently. The appearance is the same as that created by most of the painters of the period and probably has its roots in the Medieval. As some of the violins are by the Amati family (Norbert Schneider "Still Life") we know that they are not varnished with a clear varnish, nor do they look like the instruments in the paintings. We are presented with an idealised view of these instruments that is demanded by the patrons, and they must also have influenced the makers of the period.

Unless we believe that none of the great painters of the previous 200 years were able to represent the appearance of clear varnish over wood, we need to reconsider the images presented, particularly when the instruments are contemporary with the art work and can not have been greatly affected by age.

There may well still be letters etc between Baschenis and his patrons which could provide some real insight. There is a catalogue of 1972 "Un incontro bergamasco. Ceresa, Baschenis nelle collezioni private bergamasche, A cura di Marco Valsecchi, Galleria Lorenzelli, Bergamo" which might have some details. Have you seen this, or do you have the time to find it?

Cheers,

Ian

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Hi David, Bill & Guiseppe,

"A Treatise of Japanning and Varnishing" 1668 recommends that you do not let your varnish rise over and endanger your "chimny and materials", nor should you strain varnish "by fire or candle light".

I agree that it's best not to let your varnish rise over. :) If it should, there's quite a gain in safety by working with small batches.

However, my varnish strains or filters the same regardless of lighting conditions, including darkness. ;)

I think some of them treatises might not have received proper peer review....

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I agree that it's best not to let your varnish rise over. :) If it should, there's quite a gain in safety by working with small batches.

However, my varnish strains or filters the same regardless of lighting conditions, including darkness. ;)

I think some of them treatises might not have received proper peer review....

If you've not read it David, it's a real cracker! Another little nugget:

"...for should your varnish through negligence or chance take fire, value not that loss, but rather thank your stars that your self and work-house have escaped".

Ian

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Hi Ian and other, is for me too difficult to explicate (in english) the reasons over which I based my ideas, so a simple post is for me rather hard, I use simple terms and some are out of your common sense.

I agree that many makers prefer use own varnish, night and daylight made too ;-)

My guess is that the use of varnish with common features in brightness, transparency, softness etc. in many italian city could be had same source. Perhaps the friars or the monks about which Cennini speaks (chap. 40). The friars and monks in many cases were scientists, had chemical knowledge and they were in systematic sharing of knowledge between guild members. This would explain use of the "same" varnish in Italy.

Also we know there were speziali shops selling all things for varnish making also varnish just made.

Around 1750 there were a set of Historic and technological change…

Very many peoples knew the process in varnish making.

G.

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  • 2 weeks later...

Hi there, finally I got my zoom scope.

It is a little more than a toys but it has a max 200x zoom.

I bought it on ebay see

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170563927954&ssPageName=ADME:X:RTQ:US:1123

As wrote in a preview post mine varnish had some similar features than posted by Joe post #55 so I want show a couple of pics, this shot are 50x.

I'm waiting a better set lamps to shot "inside" the varnish.

G.

post-24570-0-10137900-1291643193_thumb.jpg

post-24570-0-50529100-1291643211_thumb.jpg

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"...I am absolutely confident that flame was frequently enhanced. There is a strange scarcity of information about this in old cabinet makers' texts and I only know of one early method which I will send to you, or post if anyone else is interested..."

I'm very interested...

E

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"...I am absolutely confident that flame was frequently enhanced. There is a strange scarcity of information about this in old cabinet makers' texts and I only know of one early method which I will send to you, or post if anyone else is interested..."

I'm very interested...

E

Me too!

G.

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As wrote in a preview post mine varnish had some similar features than posted by Joe post #55 so I want show a couple of pics, this shot are 50x.

In your image the craters are neither darkened nor localised around 'pores' as shown by Joe in Post#55. It looks more like a 'defect' in varnish mix and/or application rather than an intentional finishing method.

Jim

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Where did I read that the side of Stradivari's house was stained by an explosion from making varnish in an outside oven? Is this a myth? :unsure:

Mike

Bassbow,

It is hard for me to read the "pores" in your photo. The smaller craters seem to correspond to the pores in the wood...if so that is what I was talking about.

Mike,

I heard, recently, from someone whose research I trust, that the Stradivari family was involved in the wool/dye trade and the walls of their first floor were stained from the colors....

who knows?

Joe

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Hi there, finally I got my zoom scope.

It is a little more than a toys but it has a max 200x zoom.

I bought it on ebay see

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170563927954&ssPageName=ADME:X:RTQ:US:1123

As wrote in a preview post mine varnish had some similar features than posted by Joe post #55 so I want show a couple of pics, this shot are 50x.

I'm waiting a better set lamps to shot "inside" the varnish.

G.

Interesting shots G' man, those look like "pin hole crater" from shellac...er spirit varnish. Either way, that looks like a fun new toy.

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Yes it's very fun toy...

I used oil varnish.

G.

What is the "ground" {first coat} and what is the solvent type? Most any type of solvent that evaporates can leave pin holes. I feel pinholes are reduced by having a ground that "seals and fills" the pores. By doing so it will not allow the finish to pool into the "cups" of the wood pores. The pinholes are caused by the varnish skinning over on the top while the still wet "cup" continues to off gas the still "wet" solvent in those tiny areas.

Here again I don't consider pinholes a flaw really, I just consider it character ;)

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What is the "ground" {first coat} and what is the solvent type? Most any type of solvent that evaporates can leave pin holes. I feel pinholes are reduced by having a ground that "seals and fills" the pores. By doing so it will not allow the finish to pool into the "cups" of the wood pores. The pinholes are caused by the varnish skinning over on the top while the still wet "cup" continues to off gas the still "wet" solvent in those tiny areas.

Here again I don't consider pinholes a flaw really, I just consider it character ;)

Hi Jezzupe, thanks...

The ground in the red one violin is a mix of "dust", i.e. rosin diluted in turpentine gum, gypsum, calcium oxide, calcined sand, calcined bone and glass...

I let it dry about 1 year before varnish.

G.

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Me too!

G.

Dear Guiseppe & E (Actonern),

This method (which was used to dye veneers) is a bit hit and miss, but I have used it successfully - obviously it does not work on spruce.

Image 1) Make a dilute solution of lye (potash or silicate) and make a strong purple dye with Campeachy wood (not logwood). Stain the maple and, when dry, clean surface with water.

Image 2) Paint over with vinegar which turns the Campeachy yellow, but not in the deep flame.

Image 3) Surface is oiled with flour.

Another 'old timers' method is to make a dye of chewing tobacco and a 50/50 mix of ammonia and water. This can be applied in thin coats over both the pine (which can be lightly sealed with rabbit glue) and maple until the desired result is obtained.

G -

I am waiting for my USB zoom and will try to photo the Amati etc when I get it. Can you photo and post the Turmeric / Flour treatment to compare with the appearance of your wood under the varnish?

Best wishes,

Ian

post-30987-0-54609000-1291754519_thumb.jpg

post-30987-0-00342800-1291754560_thumb.jpg

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Hi Jezzupe, thanks...

The ground in the red one violin is a mix of "dust", i.e. rosin diluted in turpentine gum, gypsum, calcium oxide, calcined sand, calcined bone and glass...

I let it dry about 1 year before varnish.

G.

G,

Given this kind of wood/filling preparation, I would doubt that the pits visible in your varnish are related the pore openings.

Joe

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G,

Given this kind of wood/filling preparation, I would doubt that the pits visible in your varnish are related the pore openings.

Joe

Yes, I agree. This is why I wanted to know what the ground was. With that type of ground, and that much dry time the pores would most likely fill quite well. What we are seeing is most likely a surface tension issue related to an adhesion issue with the first coat...or inner coat out gassing pinholes not related to pore saturation.

This is why there can be "issues" {I again don't see this type of imperfection as a problem} using "mineral" grounds under oil varnish. Oil varnish's in general do not stick to "rocks" as well as Shellac based finish does. A micro fisheye can develop because the varnish is not grabbing to the "rock" which is filling the pore.

An example of wax free shellacs ability to "grab" would be in the re coat market in wood flooring. Some time ago around 2000, some finish manufactures got the great :blink: idea to put ALOX into two component waterbase finishes for use in the pre-finish wood floor market. ALOX {aluminium oxide, ie. synthetic ruby #9 on the MOHR scale, only diamonds are harder} will make a finish very scratch resistant, yet, in reality because it is suspended in the finish it is not bullet proof, so as time wet by the floors still needed to be maintained. Traditionally if a floor can be re coated before it degrades to the point of refinishing this is more cost effective and better for several reasons. Unfortunately due to this "technology" being "new" many people would attempt to re coat these floors with either oil or water base urethane as would be "standard"...Well the problem here is that one cannot visually see if ALOX is present in a finish and if you re coat it with urethane finish or ANY finish it will not bond, the finish does not stick to the powdered rock. This is where seal coat came in and literally saved the day. It is the only finsh {wax free shellac}that can effectively stick to the powdered rocks and act as a barrier coat. This then allow any finish to be put on top of it in order to have effective topcoats sick in succession.

So, Bassbows gound is "chalk full o' rocks" and therefore even if very dry. there is a high probability that an oil varnish will intermittently not adhere to "minerals"

Also, even if pooling in pores is not the culprit, pinholes can still occur randomly in areas due to outgassing, particularly with slow drying oils.

I figure you have a pretty good grasp on things Joe, this is just for "whoever"

Edit: this also would explain the potential premature chipping we see based on an adhesion issues.

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something i saw a couple years ago was a Ruggeri from 1690 that the backplate had taken a hit from a music stand deep enough to go completely through the varnish down do the ground and into the wood. I remember the hue of the pores being "pink purple" in nature like red had been stained down in the wood, but the pores of the varnish appeared to be pretty much brownish and translucent. Anyone else seen this before?

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something i saw a couple years ago was a Ruggeri from 1690 that the backplate had taken a hit from a music stand deep enough to go completely through the varnish down do the ground and into the wood. I remember the hue of the pores being "pink purple" in nature like red had been stained down in the wood, but the pores of the varnish appeared to be pretty much brownish and translucent. Anyone else seen this before?

Andrew,

Yes, I too have seen this. I think is it one of those details that some makers achieve by rubbing pigments into the wood [or their ground] prior to varnishing. When you look at these pores under magnification, one thing stands out: the material in the pore does not show any wicking [capillary action] into the surrounding [raw] wood. This gives us clues about both the viscosity of the varnish and the relative lack of absorbancy in the surrounding wood fibers.

on we go,

Joe

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How do other find these treatments affect the reflections of the flame . Ive tried various stuff and with water or alcohol soluble stuff i tend to get a dulling of the reflective properties of maple. I dont particularly like nitrites or tea for this reason.Casein seems very bad for this.Anyone know of a treatment for casein that makes it transparent?? Ive found dichromate has less flame deadening effect than nitrites.

I got an interesting effect by sealing maple with casein in two coats and followed by nitric acid which is quickly neutralised with alkali (which changes the colour from yellowish to orange like. (the treatment with acid is actually a test for protein called the xantho-proteic test or reaction.which is the cause of the colour seen when nitric acid stains your skin or fingernails).

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How do other find these treatments affect the reflections of the flame . Ive tried various stuff and with water or alcohol soluble stuff i tend to get a dulling of the reflective properties of maple. I dont particularly like nitrites or tea for this reason.Casein seems very bad for this.Anyone know of a treatment for casein that makes it transparent?? Ive found dichromate has less flame deadening effect than nitrites.

I got an interesting effect by sealing maple with casein in two coats and followed by nitric acid which is quickly neutralised with alkali (which changes the colour from yellowish to orange like. (the treatment with acid is actually a test for protein called the xantho-proteic test or reaction.which is the cause of the colour seen when nitric acid stains your skin or fingernails).

I use casein and it looks very transparent to me. Lime casein. What is your source for casein? Mine is JO-1 from National Casein (USA). I use Ms. Wages pickling lime, which contains some calcium carbonate, I believe.

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I use casein and it looks very transparent to me. Lime casein. What is your source for casein? Mine is JO-1 from National Casein (USA). I use Ms. Wages pickling lime, which contains some calcium carbonate, I believe.

But your using a casein emulsion arent you? The casein i use is an old lab jar of i think sodium caseinate (labels fell off),may be i should get some new stuff. I was under the assumption that casein dries slightly opaque . Ive been using ammonia to mix it with.

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