d Wood, we suggest several application systems for our products. This does not mean that other systems used by different luthiers cannot be used. Everyone have their own systems and experience, and can be used with our products.
The systems cover Grounds, Oil Natural Colors, and Oil Varnishes. This will allow us to generate a full universe of finishing which also can be applied to any technique for oil coatings.
With these systems we aim, as a goal, to achieve equilibrium between beauty of instruments and musical performance, helping it to get a noble aging and elegance and helping the Luthier with his work.
Old Wood suggests several systems combining our grounds, and other systems depending on the technique used for color application.
Any of the suggested systems can be used. In the examples used, we always start applying Protein primer and grounds IGG A + B.
Protein primer acts as sealing leyer and homogenizes wood capillarity, and therefore the product penetration on all instrument`s surface. This initial treatment is very important to assure the best result on the products that will follow the process.
After the primer, will follow the application of the ground IGG A + B, which gives protection and base color to the Wood. It provides transparent colour to wood fibers.
Once grounds are applied, the next step is the application of Refractive Ground and/or Mineral Grounds (Imprimitura Minerale and Doratura Minerale).
The system to be applied depends on the needs and experience of each luthier.
It is necessary to study the performance of each product when selecting systems. You can apply the refractive ground and mineral grounds, or combine the 2 mineral grounds, or use only one of these products.
In all cases, it is very important to make sure that drying process is completed right before we apply the next leyer of products. This will assure us a good adhesion and development of the product´s characteristics.
We always recommend proceeding with tests on wood pieces right before applying the products on instruments. This is just to make sure we will get the desired performance on it.
In our catalogue of products we have a detailed bibliography so luthiers can check techniques and material used.
As we did with the grounds, we suggest different ways of application for colors and varnishes.
All varnishes offered by Old Wood are resinous-oil based that contain as solvent a free aromatic compound solvent, that provides better application conditions, more safety and more comfortable to use.
Old Wood suggests two basic application systems:
The first one is applying a color glaze with one of our Oil Natural Colours or a blend of several colours, and then varnish glaze. This step will be repeated until we get the desired effect (we suggest hand application).
The second one, is to blend our Oil Natural Colours with Varnish, and then hand application, or sponge, or brush.
Lastly, we will apply the varnish leyers for finishing, and then the polishing of varnish.
In all cases, to achieve a good application of varnish, it is necessary that the surface is very flat (or smooth), very clean, and with all porosity covered to avoid unequal absorption of colored varnish.
As it happens with the grounds, the drying process has to be completed prior to the application of another leyer. If not, the final quality results may decrease.
See image scheme
Wood treatment application:
1. Protein Insulation - GELATINE solution (2 – 3%).
This consists of the application upon wood that is clean and ready to varnish of a solutioncontaining one or more protein compounds. These may be of animal origin (glue, gelatine, albumin, casein, egg yolk, etc.) or vegetable origin (gum arabic, tragacanth, cherry tree gum, sarcocollin, fig tree sap, etc.).
* L M: Condax, in research conducted in 1970 for the Mellon Institute of Pittsburgh, found thatprotein sealer (glue and albumin) was used as a primer. For his research he used microtome sections and varnish samples from a 1699 Guarneri, a Tecchler, and a Venetian instrument dated 1707.*
OLD WOOD recommends that you begin by isolating the wood, applying a 2-3% gelatine solution, and adding a small amount of albumin (egg white). For spruce, apply three coats of this solution; for maple, one is enough. It is best to apply the solution with a piece of sponge, and to use a hair dryer to dry each coat, in order to avoid internal tension in the wood. If the gelatine solution is increased with albumin, then when it is dry the instrument should be exposed to sunlight or ultraviolet light in order to boost the albumin’s properties of coagulation and insolubility.
• Albumin is obtained from egg whites, which are 85% water, 12% albumin 0.2% fat and other components. It belongs to a group of proteins that have the property of coagulating under heat. When diluted, applied in a thin coat and exposed to the light, it acquires insolubility properties under normal humidity conditions.
• Gelatine is a pure form of glue made from delicate animal tissues and which is refined with greater care and purity than ordinary glue. It is sold in thin colourless sheets or in powder form.From a chemical viewpoint, the complex proteins making ¡up the glues can be divided into two classes.
- Condroitin: Responsible for the glues’ adhesive properties.
- Glucosamine: Responsible for their gelatinous nature.
Gelatine contains more glucosamine and condroitin than glue. Its properties are more gellative than adherent. Gelatine, glue or casein will degrade at temperature above 53º C, changing colour and losing a large part of their adherent properties.
• Gum arabic and tragacanth *** are used as a primer or undercoat with very good results, by means of an old formula employed in Cremona and in other Italian city-states, and are known as “Camisega” (Tecnica Costruttiva Deggli Antichi Liutai Italiani / Euro Peluzzi).
*** To prepare tragacanth it should first be soaked in alcohol, and then dissolved in water.
• Gelatine or glue + Alum***: Successfully used since antiquity is the procedure of adding 4 -5 % de alum to the glue or gelatine, as a hardener and the make them less hygroscopic This method is used only with glues made from skin and pure gelatines. If added to bone glues, the solution will be cloudy.
*** The alum should be dissolved in water and then be applied the to glue or gelatine solution. The resulting preparation should be disposed of after use
- The Artist’s Handbook of Materials and Techniques / Ralph Mayer
- Dictionaire des matériaux du Peintre / François Perego
- Malmaterial und seine Verwendung im Bilde / Max Doerner
2. Italian Golden Ground 1700 - One or two applications
The application of one or two coats of Italian Golden Ground A+ B (PH= 7) furnishes white woods like maple, spruce or poplar, with a remarkable interior light and a lovely colour –golden cinnamon— which arises from the interior without modifying or saturating the structure, giving it a warm aspect and producing an effect similar to the exposure of the wood to sunlight over a long period.
3. Refractive Ground - One or two applications.
Refractive ground is a transparent and pale coloured compound that gives a refraction index similar to wood. Formulated without minerals, this compound enhances to a maximum level the refraction process of light. This is possible due to its processed terpenic polymers.
Refractive Ground enhances considerably, wood protection against external agents (humidity, alcalis and acids) following the line of Classical Master’s Grounds (According to the studies by Luis M. Condax.).
Its optimal surface layer penetration, avoids fibre saturation, achieving a unique lightness.
Refractive Ground is applied before mineral grounds or oil/spirit varnishes. It works as a sealer, since it avoids an excess of varnish absorption on wood, that could interfere negatively in the acoustic quality of the instrument.
Refractive Ground should be applied with hand and in one or two thin layers (use nitrile or vinyl gloves and a small brush to reach difficult parts). Its adequate viscosity and reology provides an excellent levelling on every layer applied (If desired, it can be diluted with regular solvents for oil varnishes). To force the drying, it is recommended Solar or UV exposure
4. Imprimitura Minerale - One application.
Imprimitura Minerale is a transparent ground that produces a very high refraction and enhances the acoustic properties of the instrument. It is used as a colourless primer for saturating the pores of the wood.
* In 1989 Dr. Barlow and Dr. Woodhouse published their research findings. They suggested that as a primer for antique Italian varnish, a coat of mineral particles was used in a medium of resin oil or linseed oil.
Their analyses of Stradivari instruments showed that the mineral layer was made of a mixture of minerals and other elements, but there were significant variations among instruments.
Their study did not examine self-cementing elements, puzzolana, creta, soluble glass (potassium silicate) or ground glass.*
Imprimitura Minerale should be applied by hand (use nitride or vinyl gloves) in a single, very thin coat.
5. Doratura Minerale - Two applications.
The minerals in Doratura Minerale are processed by hand to ensure a spectacular and warm, clean, and clear golden hue, which is stable under light (7), transparent, and highly resistant to oxidation and deterioration over time. Its use gives high refraction and enhances the acoustic features of the instrument.
Doratura Minerale should be applied by hand (use nitride or vinyl gloves), in two extremely thin coats.
Application Varnish and colour
1. Oil Classical Varnish - One application.
OLD WOOD’s Classical Oil Varnish products are perfectly suited for this process, but we recommend the optimum properties of Classical Amber Varnish., one of the varnishes mentioned in the oldest manuscripts, and obtained from the heating of amber, unlike Clear Amber Varnish *** - which is not made or sold by OLD WOOD – and which at the end of the 19th century began to be made using the dangerous chloroform method** and in the 20th century with rock salt *** and which was never included among the classical varnishes.
** Berger, Ernst. Beitraege zur Entwicklungsgeschichte der Maltechnik. Munich, Callwey, 1897 – 1909. Folio 389.
*** The Violin Makers Journal, June, 1961, p. 4. Robert Hill.
Classical Oil Varnish products must be applied by hand (using vinyl or nitrile gloves) in a single, extremely thin coat. A brush or sponge may be used, but the best results are obtained using the hands.
This coat operates as an intermediate sealant between the last coat of Grounds and the coat of Oil Natural Colors. By isolating the colours; saturation is avoided, transparency is assured, and refraction and dichroism are augmented.
2. Oil Natural Colors + Oil Varnish - System 1
OLD WOOD’s wide range of Oil Natural Colours what developed specifically for application to wooden instruments.
The application of Oil Natural Colours – OW. is easy and simple:
The colours are mixed, and a few drops of and Classical Oil Varnish are added as a medium.
The general application is done by hand (use nitride or vinyl gloves), and the colour is spread uniformly, in like a glaze, using a small paintbrush for the volute and other to remove excess colour from areas of difficult access.
Once the coat of Oil Natural Colors is polymerised (dry) any of the Classical Oil Varnish . Varnish may be applied as a glaze by hand (use nitride or vinyl gloves), in one single and very thin coat. The hands are best, but you may also obtain good results with a sponge of brush.
Depending of the desired objective, can be repeated once or twice more.
3. Oil Natural Colors + Oil Varnish - System 2
If you wish, you can apply colours using a brush, but you need to add enoguh color into varnish so the mix is fuild and ready for use. For this purpose we suggest Classical Amber Varnish.
Depending on the desired goals, you may need to repeat this process two or more times.
4. Finishing - One or two applications
If you wish, you can apply colors using a brush, but you need to add enoguh color into varnish so the mix is fuild and ready for use. For this purpose we suggest Classical Amber Varnish.
Depending on the desired goals, you may need to repeat this process two or more times.
A newly built instrument may be used by the musician in rehearsals and concerts at a good level, but only when the wood has attain its optimum degree of vibration and the varnish has fully hardened does it begin to develop in a state of maturity.
Finishing with oil-based varnish requires the utmost care, since the total polymerisation of this type of finish takes at least two years. The colour coats and varnish, even when dry polymerised), remain delicate and should not be subjected to rough handling or friction. This is true of all oil-based varnishes.
Polish with OW- Polish on a piece of cotton or gauze.
Polish with the utmost care, especially on the edges, the head, and rib joints, which are the areas most likely to lose color.