b'beginners guide to words: Rachel Macdonaldthe perfect dayfor paintingThe brushes are bought, the roller lies in wait in its tray, and the paint tins are just tempting you to lift the lids and unleash the colour inside but rst, take a look at the weather.Just what makes the ideal painting day? Its important toWhen waterborne paint dries too rapidly, it doesnt haveReseneget it right or chances are youll be less than satised withtime to ow out into a smooth, consolidated lm. Also,Alo Alothe results. Ideal is a tough concept, thoughlike mostthe paint dries so quickly in the brush itself that it becomesReseneCherry Piethings, youre best to aim for moderation. almost impossible to clean. ReseneResolution BlueTake temperature, for example. We typically have twoWhats more, temperature always has to be looked at it Resenetypes of paints to worry aboutsolventborne enamelsin combination with atmospheric moisture. Were notTangerineand a wide range of latex-based waterborne paints. Howtalking rain, hereits pretty obvious that you cant paintResenedoes cold affect them? outside in the rain. Were talking humidity.TurboAll paints get thick (or more viscous) in the cold and areHumidity is the amount of moisture in the air. If the air is muchhardertouse,especiallysolventborneenamels.full of moisture (i.e. humidity is high) it is slow to accept One answer is to add thinners, but this has the side-effectmore water into it and waterborne paints will be very of reducing lm build and therefore appearance. A betterslow to dry. This will lead to easy applicationbeautiful solution is to stand the paint in warm water, which makesowbut there is also a risk of water-sensitive materials it much easier to apply and helps get that smooth, brushaccumulating on the surface.mark-free nish that you want. Low humidity means the air is thirsty for moisture and will Cold temperatures can really slow down the drying timegrab it, fast, from anywheresuch as a paint lm. Low ofsolventborneenamels,butcanalsobetotallycatas- humidity, high temperatures andadditionallya porous trophic to the drying of waterborne latex paints. The plasticsurface will lead to ultra-rapid loss of water and ultra-fast particles that make up the latex binder will harden in thedrying. So fast, in fact, that the particles in the lm wont cold to the extent that they cant fuse together to formhave time to arrange themselves properly. alm.Thiscanresultincracksformingandeven,To help overcome this, hot weather additives, which can sometimes, the whole paint lm drying to a powder. slow things down a bit, can be added to the paint. And Crank the temperature up too high, however, and a newif the surface is porous, it can be pre-wetted with water set of problems surfaces. There are not any real issuesbefore the application of waterborne paints.with the solventborne systems, but waterborne systems can just dry too fast.90 |'