Derek McCormick’s Violin Blog

Making a violin and other violin-related topics

VARNISHING

Materials

These are some of the materias used in "varnishing". Technically the process is not really varnishing - it is more akin to the classical method of oil painting. The wood is first treated with a primer and "ground". This is followed by a sealer which prevents the later colour layers from infiltrating the wood. Then a series of coloured coats are applied. These consist of pigments suspended in a resin/oil varnish, so this is technically paint rather than varnish. Finally, after all the colour layers, a coat of clear varnish is applied over the surface. The brushes that I use are in the foreground. The broad brush with dark hair is used on the front and back. The narrower, slightly stiffer brush is used on the scroll and ribs (it is also a different "filbert" shape).

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Here I have removed the fingerboard and replaced it with a thin piece of wood to avoid damage to the delicate edges of the neck. The primer (Imprimatura Dorata from Magister) has been applied.

The vioin

If I lived in Italy I would now hang the violin in the sun for a few days! In this climate I resort to my UV box to enhance the colour of the wood and primer. (The box noramlly has the lid closed. For obvious reasons I took this photo with my eyes closed!!)

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In the next stage I will be rubbing a paste of pumice onto the wood. Pumice is a porous volcanic rock which is available in powder form and I start by mixing it with clear varnish and mulling it to ensure fine particle size and to suspend it evenly in the varnish. After scooping it into a jar with a palette knife I apply it by using a cloth "rubber".

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Another mulling session - this time I am using the pigment Cinquasia Gold. This will be added to the varnish (plus some Gilsonite) to colour the varnish in subsequent steps.

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Several coats of varnish have now been applied. After each coat dries it is rubbed down with very fine micromesh abrasive lubricated with water and Marseilles soap.

The varnishing process continues with successive coats being applied with a gentle rub-down between layers. However, the composition of each coat is not the same. The major components of my varnish are pine resin  and linseed oil, and I get this from Northern Renaissance Instruments who make it by hand in their premises near Manchester. Before using it I add pigments and turpentine.  Each coat of varnish has a slightly different oil:resin ratio. The first coat has a ratio of 0.9:1.0 and the proportion of oil is gradually increased with each successive coat until the final coats have an oil:resin ratio of 1.5:1.0. As a result of this, the lower coats of varnish are quite stiff and the upper coats are considerably softer and more elastic.

When the final coat has bee applied I leave the instrument for about a week before rubbing down with progressively finer micromesh abrasives.  The final polishing process will come later when everything is ready for final set-up. I aim for a soft sheen  rather than a high gloss lacquer-like finish.

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October 13, 2009 - Posted by | (18) Varnishing

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