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Home >>Professional Decorating>>Decorating Museum>>Ropiness
Decorating Defects - their cause and cure
Ropiness
The defect known as " ropiness" is often ascribed to brush marks, since
the effect is almost precisely the same in each case.
There is, however, a distinction, for while the presence of brush marks can usually be put down to lack of skill or proper tools on the part of the operative, ropiness is due to an inherent fault in the material.
It may be described as a lack of the necessary flowing properties in a paint, enamel, or varnish, the result being that the furrows left by the action of the brush remain just as they are and the material does not find its own level.
It may be caused by shortcomings on the part of the manufacturer or to conditions under which the paint has been stored or used.
If the store or shop in which it is kept is not heated during a cold spell, the driers or other constituents of the paint may be chilled out in a fatty form; in such circumstances, the slight warming through of the offending material might cure this fault, especially if a small proportion of xylol, a heavier and less volatile solvent than benzol,is used for thinning purposes.
Ropiness may also occur when thinners of too volatile a type are added to a paint used when the temperature is high. The remedy is to use a heavier type of thinner or to avoid painting in extreme heat when the paint sets up too quickly under the brush.