Timber surface must be abraded, clean and dry, with dust, dirt, wax and grease removed. Mould and algal growth must be
eradicated using a suitable solvent. The moisture content of the timber must not exceed 18%. This figure will be 14% or
lower for interior timbers. Degrease any exposed bare timber surface by wiping with a cloth dampened in a suitable solvent.
Any hard crystallised resin at the surface of the timber should be removed with a scraper. Remaining resinous residues may
be removed using a suitable solvent. Knotting may be used to reduce extractive discolouration, however, knotting is not
always fully effective in “sealing in” resin. In addition, the adhesion of subsequent coatings may be impaired. New Timber : Where a superficial application of preservative to softwood and hardwood is deemed necessary, such as timbers in Durability Class 3 or lower, use Cuprinol Wood Preserver Clear (BP). For Class 4 (in ground contact) and 5 (marine) use pre-treated wood specific for these conditions. Preservative pre-treatments must be fully dry before the application of Rubbol Primer Plus. Do not use on substrates which have had water-repellent preservative pre-treatments applied. Where possible, the first coat should be applied all round prior to fixing.Only use non-ferrous screws, nails and fixings.