Page:Cyclopedia of Painting-Armstrong, George D (1908).djvu/154

From Wikisource
Jump to navigation Jump to search
This page has been validated.
146
CYCLOPEDIA OF PAINTING

tough and seems to be firmly adhering to the wood, but to repaint the surface requires a great deal of care in keeping the new paint from following the first coats and cracking in like manner. Be careful not to have an excess of paint on the surface, as such will blister and peel.

Thoroughly clean the surface with a wire brush. Mix the first coat of paint fairly elastic or with 1 pint to 1+12 pints of turpentine to a gallon of paint. This will not dry too hard and will be sufficiently elastic to withstand contraction and expansion over this treacherous surface, also penetrate to a good depth. Brush out well and do not attempt to fill the cracks with this coat. The finishing coat should be mixed to a good consistency with 1-32 to 1-16 gallon of turpentine to the gallon of paint and be well brushed over the surface. If, however, all of the old paint is solid and dried through, a half-elastic coat, 14 gallon of turpentine to a gallon of paint, can be applied and should be well brushed into the cracks. This will dry firm and hard and a second coat of elastic paint can be applied over it. This, well brushed into the cracks, will to a certain extent fill them and make a very passable job without danger of blistering, which would be the result if a first coat of very elastic paint had been applied.

Alligatored Paint. Where the paint is cracked in every direction, forming blocks, triangles, and in fact, every conceivable shape, it is called alligatoring. This comes from a number of causes, but can usually be traced to non-drying undercoats and heavy coats of different mixtures. Ochre or similar slow-drying pigments mixed with boiled oil will very often be found at the bottom of this trouble. Fatty paint or the use of adulterated oil also causes paint to alligator. Such paint is usually tough and hard except where it is well protected and there the undercoats will be found to be tacky and spongy. The only successful way to repaint this surface is to burn off the paint. This is a very difficult job, as the heat softens up the excess of oil and a