Post by 1dave on Aug 22, 2020 15:50:47 GMT -7
Something I have done in wood and want to try in metal.
Cover the surface with wax, place negative on it, shine a hot light above until the wax melts away from the dark spots, put acid in the hollows until etched to the desired amount. Wash with water and baking soda.
I checked Sharr's "Creative Gold and Silversmithing" book.
Chapter 20 starts on P. 185. She says to "coat all areas of the metal that are not to be etched with black asphaltum varnish. Thin with turpentine
www.farwestpaint.com/Catalog/A-A-1632.htm
A-A-1632 Vitanic Black Asphalt Varnish COLOR NO. 17038
COLOR(S): Black.
PRODUCT TYPE: Gilsonite Varnish.
DESCRIPTION: A weather-proof, elastic, iron paint for interior or exterior application. It seals out rust-causing air and water and develops excellent adhesion to a variety of metal surfaces, including new or rusted steel or aluminum surfaces. MEETS SPECS.: TT-V-51, Commercial Product #40 Vitanic Black Iron Paint.
Intended Use: For new or rusted steel, or aluminum surfaces.
PHYSICAL CHARACTERISTICS
VISCOSITY: 46"-60" (FORD 4)
DRY TO TOUCH: 1-3 hours
WEIGHT SOLIDS: 39-41%
TACK FREE: 8-12 hours
VOLUME SOLIDS: 36-38%
TIME TO RECOAT: 24 hours
WEIGHT PER GALLON: 7.30 lbs. per gal.
DRY HARD: 24 hours
V.O.C.: 525 grams per liter
COLOR RANGE: Black
FLASH POINT: 105° F.
PACKAGING: 1 or 5 gallon containers
BATCH: Stock
PRACTICAL COVERAGE: 300-500 square feet per gallon depending upon application method, porosity and smoothness of surface.
SURFACE PREPARATION: Remove loose rust with Farwest #695 Rynolite Chemical Cleaner-Etcher and wire brush. Surface should be free of foreign particles and contaminants. Galvanized surfaces should be treated with a phosphoric etch before applying product.
APPLICATION: Stir thoroughly. Brush, roller, or spray.
THINNING: Product should not be thinned unless absolutely necessary. Thin, if necessary, with Farwest #602 Mineral Spirits.
CLEAN-UP: Tools and equipment may be cleaned with Farwest #602 Mineral Spirits.
COLOR(S): Black.
PRODUCT TYPE: Gilsonite Varnish.
DESCRIPTION: A weather-proof, elastic, iron paint for interior or exterior application. It seals out rust-causing air and water and develops excellent adhesion to a variety of metal surfaces, including new or rusted steel or aluminum surfaces. MEETS SPECS.: TT-V-51, Commercial Product #40 Vitanic Black Iron Paint.
Intended Use: For new or rusted steel, or aluminum surfaces.
PHYSICAL CHARACTERISTICS
VISCOSITY: 46"-60" (FORD 4)
DRY TO TOUCH: 1-3 hours
WEIGHT SOLIDS: 39-41%
TACK FREE: 8-12 hours
VOLUME SOLIDS: 36-38%
TIME TO RECOAT: 24 hours
WEIGHT PER GALLON: 7.30 lbs. per gal.
DRY HARD: 24 hours
V.O.C.: 525 grams per liter
COLOR RANGE: Black
FLASH POINT: 105° F.
PACKAGING: 1 or 5 gallon containers
BATCH: Stock
PRACTICAL COVERAGE: 300-500 square feet per gallon depending upon application method, porosity and smoothness of surface.
SURFACE PREPARATION: Remove loose rust with Farwest #695 Rynolite Chemical Cleaner-Etcher and wire brush. Surface should be free of foreign particles and contaminants. Galvanized surfaces should be treated with a phosphoric etch before applying product.
APPLICATION: Stir thoroughly. Brush, roller, or spray.
THINNING: Product should not be thinned unless absolutely necessary. Thin, if necessary, with Farwest #602 Mineral Spirits.
CLEAN-UP: Tools and equipment may be cleaned with Farwest #602 Mineral Spirits.