Lap Marks: Painters Painting Vancouver

LAP MARKS

Lap marks (Figure 14) sometimes occur where wet and dry layers overlap during the application of paint or stain. This non uniform appearance can be caused by a number of situations such as working too long in one area when painting, too much heat or draft during application, too porous a surface, or the use of an improper thinner. Too much heat or draft causes a rapid loss of solvent and speeds up the setup time, resulting in a thicker film wherever overlapping occurs.

Solution For Lap Marks

Another coat of paint, spread uniformly, is necessary to block out lap marks. If the finish coat is relatively transparent or the surface overly porous, a second coat or a primer coat should be applied.

To avoid lap marks, do not paint one section of a building from top to bottom completely. Instead, paint in small sections as defined by length or width of boards so there is no time for one to dry completely before starting on the adjacent one. However, top to bottom painting is appropriate on siding shingle surfaces since they provide natural breaking points.

Low-luster exterior paints that are highly pigmented require special application techniques. Unless a wet edge is maintained, brushing back into a semi-dry area will double the coat and result in shiners in these places. Work in limited areas to maintain a wet edge, even if it means doing one board at a time.

Painting on hot, windy days speeds up drying time; avoid painting on these days. Add thinner sparingly if it is needed.

Rick Anderson

www.vancouversbestpainters.com

call: 604-painter