1722 Spirit Varnish
-45g seedlac or amber shellac
-5g gum mastic
-5g gum sandarac
-3g frankincense
-250mL ethanol
-5mL lavender spike oil
Place all ingredients in a partially-open glass jar and allow to dissolve for 72 hours, stirring 4x daily until fully dissolved and no more lac or resin sticks to the bottom of the jar.
When completely dissolved, strain through coffee filter or 4 layers of cheese cloth into a clean, dry jar. Repeat until the filter no longer collects dirt, usually 3 times. Since ethanol evaporates during the dissolution process, thinning with 50mL ethanol may be required at this point to achieve brushing thickness--keep some extra on hand, for this.
Recipe yields a nice, amber varnish which adheres well between coats thanks to the mastic, and dries shiny thanks to the sandarac. UV curing optional, but encouraged. Tint with alcohol inks--alizarin crimson for auburn, burnt umber for mocha.
I apply in 7 thin coats using a 1" chip brush. One coat natural amber, 2 colour coats (if desired), then 3 coats more of amber, allowing to dry for 3 hours between coats, then 48 hours after the last coat I scuff with 000 steel wool before rubbing in one more coat of amber with a lint-free cloth, then allow to dry a further 48 hours before stringing and adding fittings.
1722 Oil Varnish
-45g clear pine rosin
-5g gum mastic
-5g gum sandarac
-3g frankincense
-350mL raw linseed oil
-5mL lavender spike oil
-3mL walnut oil
Place first 5 ingredients in a glass jar, and place jar into a metal pot. Heat the resins/gums/jar/pot on a hot plate or gas burner outside over medium heat for 2-3 hours, supervising constantly and stirring frequently with a fireproof glass rod. It'll smoke heavily at first as impurities burn off and oils and resins polymerize--don't breathe it in. Remove it from the heat, and allow it to cool for 30 minutes before slowly adding a blend of the remaining 4 oils a little at a time. This should gel the resins, but if the oil starts boiling instead, step back and grab an extinguisher. Place the jar back into the pot, and continue to stir, supervise and heat over medium heat for a further 3-4 hours, until most of the resinous gunk has dissolved. Filter through 4 layers of cheesecloth when still hot, and repeat until the filter no longer picks up dirt/soot.
Recipe yields a nice amber varnish. Tint with transparent oil paints, 1 drop of red oxide for auburn, 2 drops of burnt umber for mocha.
Once cooled, I apply in 2 coats using a gloved hand and/or a lint-free cloth pad, first a colour coat which I allow to dry for 2 weeks, then quick scuff with 000 steel wool, and a coat of amber applied similarly, which I allow to dry for 4 weeks before adding strings and fittings. UV-curing is required, either with a blacklight bulb, or in near-direct sunlight for the duration of the drying period.
Oil varnish is great for building a richly-coloured finish without obscuring the chatoyance of the underlying wood, and for appeasing hyper-traditionalists like me.
-45g seedlac or amber shellac
-5g gum mastic
-5g gum sandarac
-3g frankincense
-250mL ethanol
-5mL lavender spike oil
Place all ingredients in a partially-open glass jar and allow to dissolve for 72 hours, stirring 4x daily until fully dissolved and no more lac or resin sticks to the bottom of the jar.
When completely dissolved, strain through coffee filter or 4 layers of cheese cloth into a clean, dry jar. Repeat until the filter no longer collects dirt, usually 3 times. Since ethanol evaporates during the dissolution process, thinning with 50mL ethanol may be required at this point to achieve brushing thickness--keep some extra on hand, for this.
Recipe yields a nice, amber varnish which adheres well between coats thanks to the mastic, and dries shiny thanks to the sandarac. UV curing optional, but encouraged. Tint with alcohol inks--alizarin crimson for auburn, burnt umber for mocha.
I apply in 7 thin coats using a 1" chip brush. One coat natural amber, 2 colour coats (if desired), then 3 coats more of amber, allowing to dry for 3 hours between coats, then 48 hours after the last coat I scuff with 000 steel wool before rubbing in one more coat of amber with a lint-free cloth, then allow to dry a further 48 hours before stringing and adding fittings.
1722 Oil Varnish
-45g clear pine rosin
-5g gum mastic
-5g gum sandarac
-3g frankincense
-350mL raw linseed oil
-5mL lavender spike oil
-3mL walnut oil
Place first 5 ingredients in a glass jar, and place jar into a metal pot. Heat the resins/gums/jar/pot on a hot plate or gas burner outside over medium heat for 2-3 hours, supervising constantly and stirring frequently with a fireproof glass rod. It'll smoke heavily at first as impurities burn off and oils and resins polymerize--don't breathe it in. Remove it from the heat, and allow it to cool for 30 minutes before slowly adding a blend of the remaining 4 oils a little at a time. This should gel the resins, but if the oil starts boiling instead, step back and grab an extinguisher. Place the jar back into the pot, and continue to stir, supervise and heat over medium heat for a further 3-4 hours, until most of the resinous gunk has dissolved. Filter through 4 layers of cheesecloth when still hot, and repeat until the filter no longer picks up dirt/soot.
Recipe yields a nice amber varnish. Tint with transparent oil paints, 1 drop of red oxide for auburn, 2 drops of burnt umber for mocha.
Once cooled, I apply in 2 coats using a gloved hand and/or a lint-free cloth pad, first a colour coat which I allow to dry for 2 weeks, then quick scuff with 000 steel wool, and a coat of amber applied similarly, which I allow to dry for 4 weeks before adding strings and fittings. UV-curing is required, either with a blacklight bulb, or in near-direct sunlight for the duration of the drying period.
Oil varnish is great for building a richly-coloured finish without obscuring the chatoyance of the underlying wood, and for appeasing hyper-traditionalists like me.