Iron corrosion; anti-fouling and anti-corrosive paints . and the incorporation of ochre or iron oxide in thesame varnish will produce a paint taking twenty-four hoursto dry; and there are other pigments, lampblack for ex-ample, which will prevent this otherwise fairly quick varnishfrom drying at all when used as paint. The pigment, as wellas the conditions of temperature and moisture, must there-fore be taken into account in testing the drying capacityof a paint. IBON-COEBOSION AND ANTI-COREOSIVE PAINTS. 89 With regard to the behaviour of a pigment, its capacityfor absorbing hnseed oil or hnse
Iron corrosion; anti-fouling and anti-corrosive paints . and the incorporation of ochre or iron oxide in thesame varnish will produce a paint taking twenty-four hoursto dry; and there are other pigments, lampblack for ex-ample, which will prevent this otherwise fairly quick varnishfrom drying at all when used as paint. The pigment, as wellas the conditions of temperature and moisture, must there-fore be taken into account in testing the drying capacityof a paint. IBON-COEBOSION AND ANTI-COREOSIVE PAINTS. 89 With regard to the behaviour of a pigment, its capacityfor absorbing hnseed oil or hnseed varnish, and its influenceon the drying and hardening of the latter constituent, themost suitable paint for the preservation of iron structureswill be the one that contains a pigment requirimj a large ad-mixture of linseed oil or linseed varnish in order to render itdistributable, and which exerts no influence, favourable or thereverse, on the drying and Jiardening of same. In applying paint to either v^^ood or iron the followingrule holds good :—. Fig. 42 (magnified).—Cracks in an oil paint, with another, intermediate layer. Each previous coat of paint must be perfectly dry before thefollowing coat is laid on. If a fresh coat be applied on onethat is not yet quite drj, risk is incurred of the paint beingdrawn, under the influence of heat (the sun), whereby blistersare produced. These may vary in depth, and if they extendto the lowermost coating may leave the surface of the metalexposed underneath the blister, so that when the lattercracks, under mechanical influences or on further drying,the unrestricted admission of moisture to the iron ensues. 90 mON-CORKOSION AND ANTI-COEEOSIVE PAINTS. Hence rust inevitably follows, and, as it progressively in-creases, lifts the paint from the iron in many places, andfinally causes it to fall off. The way in which this blisteringproceeds in paint, by the action of underlying rust, can beseen from Fig. 17, where a simple coat of varni
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectcorrosionandanticorr
