@sizing @protein Wood sizing before varnishing

[guminarviolin]

Hi Makers,

What do you think about "sizing"? Greiner writes that in Stradivari's time they probably used protein, which is casein... 

Have a nice day! 

Tamás

Edited January 15 by guminarviolin

[Don Noon]

"Protein" could also include hide glue.  I think both do somewhat the same thing: sealing the wood to prevent oil varnish from soaking in, but with the side effect of giving a washed-out appearance.  Think of "glue ghost" effect, which can be reduced by diluting the glue or casein.

I only use casein on the inside surfaces, where appearance isn't important, and it gives a bit of sealing and stiffening without adding much mass or damping.  On the outside, I prefer a spirit varnish sealer for appearance.

[guminarviolin]

Thanks for your reply, Don!

 Does spirit varnish-based "sealing" allow you to freely shape and paint the surface irregularities of the wood? Does the color not wash into the wood?

[Andreas Preuss]

On 1/14/2025 at 4:24 PM, guminarviolin said:

Hi Makers,

What do you think about "sizing"? Greiner writes that in Stradivari's time they probably used protein, which is casein... 

Have a nice day! 

Tamás

Since you are quoting Greiner, I guess you are looking for a classic Cremonese appearance. 
 

Just for a clear reflective ground glue isn’t bad. (Just as many violins from Markneukirchen) 

If it comes to imitate the appearance of old Italian violins, there is much more. In my own view wood treatment is one of the necessary components which makes the golden ground possible. (Or, on untreated white wood the same ground wouldn’t produce the same Color effect) This in turn is the necessary condition to use a varnish of low color intensity whose color effect is getting ‘amplified’ by the ground. 
 

Jo napot kivanok. 
 

Andr(e)as

[guminarviolin]

Szervusz András!

(Nem ismerjük egymást személyesen, de nagyon örülök, hogy itt találkozunk, sokat hallottam Rólad!)

I'm really looking for the classic Cremonese look. Greiner writes quite in detail (although he only describes his opinion, he does not detail the scientific studies), and although he ignores the oxidized color of the wood, e.g. mentions the five-fold moistening and scrapering...

Nice to meet you,
Tamás 

[Will Turner]

Several Cremonese makers are providing YouTube videos on their sizing with protein.    

Edgar Russ

Ep. 73: My and Strad's woodpreparation

Davide Sora

Applicazione del Mastice e Trementina (condensed version) (read the notes, has english section).     Davide in this one shows his application of refractive ground.    Another important step.

 

[Will Turner]

Been pondering the use of plain, unflavored and unsweetened Greek yogurt.   Mixed with pumice, rubbed off after application so it is just in the surface of the wood.

Both casein and calcium are in quantities.  

Probably crazy, but might try it out next violin.   Always reminds me of the casein/calcium preparation typically used.

[Davide Sora]

58 minutes ago, Will Turner said:

Been pondering the use of plain, unflavored and unsweetened Greek yogurt.   Mixed with pumice, rubbed off after application so it is just in the surface of the wood.

Both casein and calcium are in quantities.  

Probably crazy, but might try it out next violin.   Always reminds me of the casein/calcium preparation typically used.

Does yogurt form a hard film when dry? It might work in this case, but I suggest testing on plastic sheets and wood scraps before putting it on the violin.

[Will Turner]

Thank you, I will test it as you suggested. 

[Davide Sora]

11 hours ago, Will Turner said:

Thank you, I will test it as you suggested. 

Give us feedback, curiosity is killing me.

[Will Turner]

Have some maple scraps to test.  Will do it and take a picture.

[Will Turner]

Looks like it will work.  Here’s the example, not precise but demonstrating the sealing.  I would then scrub off more on the violin.

 

 

Will varnish the scrap to make sure it doesn’t bleed through the oil varnish.  Will show the bleed through on the untreated part too.

ingredients are just the milk and yogurt cultures. 

Edited January 22 by Will Turner
Clarification on ingredients

[Don Noon]

I wouldn't trust any ground until I see what it does on figured maple, with the full varnish over it.  Unless the idea is to have an opaque paint as the final coating, then it doesn't matter much.

[LCF]

In essence it's a type of acid (coagulated) casein but the effect you've got there resembles liming in appearance. The lactic acid component might be a bit reactive to water and it will have some milk fat in it. I suspect it would be safer to wash it and  drain it well for several days in cheese cloth. Then if you don't like it as a ground you could have it on toast with a little oil, salt, and herbs. Yum. 

[FiddleBasher]

If the violin is to be stained. Do you seal all of the violin or only the top then put on the stain?

[guminarviolin]

What do you mean by stain?

[Don Noon]

"Stain", as commonly understood in woodworking, is something I would never use anywhere on a violin.

Color getting into the wood generally looks bad on spruce but can (in moderation) look nice on maple, so I would want to seal the spruce moreso than the maple.

[David Beard]

'Sizing' was such a normal and frequent process in historical woodworking, but also across all the arts and industries.

It's very difficult for me to believe it wasn't a frequent process in the old violin workshops.

But, 'sizing' did not mean a glazing over with a binder.   Sizing implied diluting the binder appropriately so it would 'unify' a material without covering the material.

With a sizing before finishing work, I believe you would want a very thin consistency.  Just enough to lightly inhibit deep absorption and propagation of oil, but leaving surface texture, structure, and pores nearly entirely open.

If your sizing glazes that wood in the least, you'll get Don's ghosts.

[Will Turner]

I’ve ditched the Greek yogurt size, even when I tried another sample and scrubbed it, the point it doesn’t mute the grain also didn’t keep a clear oil varnish from entering the grain more than expected. 
Properties of casein is that it has less of the unwanted milk solids.   Was worth trying but glad to use scrap wood than actual spruce top.

[FiddleBasher]

On 1/23/2025 at 1:46 PM, Don Noon said:

"Stain", as commonly understood in woodworking, is something I would never use anywhere on a violin.

Color getting into the wood generally looks bad on spruce but can (in moderation) look nice on maple, so I would want to seal the spruce moreso than the maple.

Thank you Don, would gamboge be considered a stain. I reading it is dangerous to health but some people use it. Not having uv box I am testing tea and coffee stain on small pieces of Maple and spruce. 

[Don Noon]

I know nothing about gamboge, and have never tried it.  I know I tested tea, but I don't remember the result; presumably I didn't like it, since I don't use it now.  There's free UV outside if you don't have a UV box.  For darkening wood, a dilute base can work (opinions vary about what it might do to degrade the wood).  I prefer torrefying, which results in wood that is quite dark.  I stick to the concept:

1. Get the wood the proper shade (UV, chemical conversion, torrefying)
2. First on the wood: very light color, something that doesn't soak too far into the wood, but doesn't just lay on the surface.  It has to wet the wood to some degree. Optional thin casein coat first, not a true sealer.
3. Oil varnish, color coats.
4. Optional clear coat or polish

Everything as transparent as possible.  Test everything on appropriate offcuts first!

[guminarviolin]

What exactly do you mean by torrefying?

[Bill Yacey]

Baking the wood in an oxygen free atmosphere to color the wood.

[Don Noon]

https://pacificrimtonewoods.com/pages/thermal-modification

[Nick Allen]

On 1/23/2025 at 8:46 AM, Don Noon said:

"Stain", as commonly understood in woodworking, is something I would never use anywhere on a violin.

I would respectfully disagree here. 

A great deal of the best makers are using some kind of colored element in the wood. 

If executed correctly, with the correct materials, stained wood can have an optical quality that is hard to beat. But the difference maker is when and what and how to apply your materials. 

Also, some degree of "burning" of the wood seems to be quite desirable in order to achieve a really dynamic look. And no burning as in what we usually think, like haphazard pigment/stain application, but rather manipulation of flame contrast and highlight. 

If you don't get any color into the flames, then the wood will just look 1 dimensional, to my taste at least.