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December 12, 2009
1. What is the formula for mixing pigment e.g., burnt umber to shellac? I'm going for the old looking dark orange result or chocolate mahogony.
2 May Linseed Oil be used as an undercoat to the above?
3. May a Chocolate mahoghany finish be placed over a stripped piece formerly red?
hobbyist - Harrisburg, Pennsylvania
First of two simultaneous responses -- December 15, 2009
What you want to do . . . to make your own paint or dyed lacquer? If you want to make paint mix 20% shellac solution and pigment, if you want dyed lacquer then you can dye shellac solution with woodworkers dyes.
- Zagreb, Croatia
Concentrated NGR Stains
Second of two simultaneous responses -- December 15, 2009
Well for the life of me I have no idea why you would want to mess with shellac finishes and I'm not going to ask. I use the stuff all of the time but ONLY under protest! I NEVER use any sort of oil based finish when I am working with shellac. I have always found that the shellac will not bond to oil base stains and finishes. As for pigments I buy the closest color flakes I can get and assume that they will get a couple shades lighter after they are cut and I add pigments to the cut solution and paint it onto a test piece of wood until I think I have it. I prefer to use a very light colored shellac and try to get my color with a stain or wood dye. If you are shellacing metal, glass or ivory this is not an option of course. I always use aniline or NGR stains. Many other stains have oil in them and take forever to dry and shellac does not adhere well to any oil finishes. On top of that if there is moisture or unhardened oil on the wood the shellac will lift and peel off. The wood must be 100% stable before applying your shellac. If you opt to add your tints to the shellac solution and forgo staining or dying the wood remember that your finish will get lighter as you buff or polish it out as the finish will be getting thinner as you cut it down. Its always best to color the wood and then put a lighter colored coat of shellac on top. Shellac finishes are extremely easy to damage. Dropping coins from a height of 6 inches will often white dent them and setting a hot cup of coffee on a shellac table top will melt right down to the wood. I am FORCED to work with it because many period guns use that type of finish and the customer is always right even if he is really really really really really bloody WRONG! My method for mixing shellac is as follows. Place prepped parts into a warm area, the warmer the better. Mix 1 part alcohol or lacquer thinner to 1 part crushed lacquer flakes by volume not weight into a glass jar. Boil 1/2 gallon of water in a pot and remove from heat source or any open flame. Place the jar with solution into the pot of hot water and stir adding more flakes. When no more will dissolve pour through a coffee filter and roll on to the work piece with a 4 inch lint free paint roller. Re-coat after 30 minutes until you are happy with the depth of the finish. Buff with fine auto buffing compound and soft leather. Finish with Birchwood Casey stock sheen and conditioner and a cotton rag. Do not do this indoors or near open flame and for gods sake don't smoke while doing it! Aniline NGR stains can be removed from the hands with a large knife or hatchet. Stains on clothing can be removed by burning the affected area or clothing with common fire!
Edmonton, Alberta, Canada