Page:Cyclopedia of Painting-Armstrong, George D (1908).djvu/158

150 primer has been used, causing the paint to peel from its not having penetrated the surface, only a small proportion of oil having gone into the wood, it is very easy to remove with a burning lamp, leaving a surface which is practically new, as most of the oil will have been drawn from the wood during the process of burning. This surface can then be treated the same as any new wood, with possibly the exception of some protected parts where the oil has penetrated to a greater depth and the paint is in better condition than on exposed parts. The cause of blistered and peeled work can often be traced to too elastic a coating of paint having been applied over a burned surface. This is especially true where boiled or heavy oil has been used in the primer of the paint which was burned. Boiled oil should never be used in a paint applied over a burned surface, it will not penetrate but will lay on the surface and will soon crack, blister and peel. These troubles are often laid to dampness or the paint used, or some defect in the building which supposedly did not allow the paint to properly harden, while the true cause is from the paint not having been properly reduced or applied over the surface.

Blistering. When paint blisters, the cause is usually attributed to dampness, and it is perhaps true that more trouble of this character on new buildings can be traced to wet or unseasoned lumber or fresh plastering, than to any other cause, and on old buildings to bad roofs, leaky gutters, broken down spouts and wet basements. There are so many chances for dampness to get under the paint of either new or old buildings that it naturally follows there would be more blisters from this cause than from all others.

As to buildings being in the foregoing condition, the weather before and during the time the paint is applied has much to do with it.

Dampness causing blistering of paint is more easily detected than any other condition. This is especially true where the dampness comes from wet plastering, as the