IF YOU USED A PROFESIONAL AIRLESS SPRAY UNIT AVAILABLE FROM ALL GOOD HIRE SHOPS INSTEAD OF THE CHEAP DIY ELECTRIC UNITS YOU CAN BUY FROM B&Q ECT YOU SHOULD HAVE NO PROBLEMS,I USE AN AIRLESS SPRAY UNIT REGULAR TO SPRAY EXTERIOR PEBBLEDASH ON HOUSES ECT,IT CAN CUT A 2 DAY JOB DOWN TO 4 HOURS,BUT...