Saturday, January 14, 2012

How to Varnish

Varnish, let’s talk about it.
Are you worried about varnishing because you dont know enough about it? Recently we have had quite a few enquiries about varnishing, so we thought we would supply some tricks and tips to help you become a master varnisher.

The following is an edited version of what can be a complex and tricky process to embark upon. The St. Lukettes have written a distilled list of the essential peices of information to help you understand varnish and to help you varnish better.

Retouch Varnish = is a low resin content varnish that allows the oxygen to access the paint surface for hardening of the oil paint. It is the only varnish to be used before the painting has fully hardened (dried).
Generally it takes 3-6 months for oil paint to absorb enough oxygen to fully harden at which point a final picture varnish can be applied. Retouch Varnish is made from resin and no matting agent so it will not reduce gloss levels on your painting. Aerosol versions of this product require longer drying times to liquid based versions so to be in the safe side please wait until your painting is dry as it is not a true Retouch Varnish.

Final Picture Varnishes (Gloss, Satin and Matt) = Varnishes have two major functions;Firstly to create an even reflective finish of a specific gloss or mattness. Secondly the varnish is a sacrificial coat that will collect future dirt and grime. The dirty varnish can be easily removed at some future point without destroying any of the paint film underneath. All Langridge and GOLDEN solvent-based retouch and picture varnishes (except damar varnish) are based on synthetic resins dissolved in White Spirit. Do not use alternative solvents for dilution or clean-up.

Damar Varnish = A traditional varnish made from natural damar resin dissolved in Distilled Gum Turpentine. Clarified and double filtered, it dries to a gloss finish.

GOLDEN MSA Varnish (Gloss, Satin and Matte) = Synthetic resin based final picture varnish for use on or oil and acrylics paintings. Thin with Artists White Spirits prior to use.

GOLDEN Polymer Varnish = This is a unique fully-reversable, water-based varnish to be used on acrylic paints.

All GOLDEN varnishes include high levels of Ultra-violet stabiliser prevent fading of sensitive colour layers such as digital prints.

For examples of the different reflective finishes come in to see our varnish sample banner instore. To attain more information and MSDS’s please visit the Langridge website.

How To Apply
First you must read the label, then re-read the label. If you need to thin your varnish with White Spirit, Turpentine, water or shake the can for a minimum of 2 minutes then this is what you must do. Always test your varnish before applying it to your masterpiece that is required to be on the gallery wall tomorrow.

Situate yourself in an area away from dust, pet hair and dirt. If you are using a liquid varnish, pour it into a clean non-spill container made of glass or ceramics. With a clean brush dip the first centremetre of hair filament into the varnish and then immediately wipe the brush against the lid of the container disposing of any excessive amounts of varnish. Thinly apply the varnish over a small squared area of the canvas in a vertical and then horizontal motion.

Repeat this process until the entire surface has been covered. With this method you can be sure that the square application of varnish will overlap resulting in no missed areas. It always helps to varnish under natural lighting so that you can identify any dull areas where you may have missed applying the varnish. Always varnish an artwork lying down so that no dribbling occurs. Try to varnish as thinly as possible, more is not better and building up thin layers is always more desirable than pooling the varnish on.

Matte and Satin varnish contains a product called Matting Silica. Matting Silica is a fine particulate that knocks the gloss finish back. Matting Silica is quite heavy and tends to sit on the bottom of the can or bottle, if you do not thoroughly mix the separated out materials before applying the varnish the resultant layer of applied varnish could streak or turn white. If this has happened you must remove the varnish with the correct solvent and start again.

Underbound paint layers, i.e. areas of paint that do not have enough binder will cause varnish to sink in creating a varnish/no varnish streaking effect across your painting. If this is happening you may want to consider completing an isolation coat before you begin to varnish. Please come into St Luke and talk to a st lukette if this is an issue as it is always case sensitive and there are many factors that cause this problem. If you are using acrylics please follow the link below to see some information available on Golden’s youtube channel.

To varnish properly you need a specialty varnishing brush. St Luke recommends a synthetic short handled brush with very fine hair filaments. A varnishing brush should always be used for varnishing alone and great care needs to be taken to clean it thoroughly, then form it back into shape and store it for the next occasion.

St Luke stocks the full range of Langridge and Golden Varnishes. Our store catalogue is now online and can be accessed here on our blogspot.

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