Boat painting : do i need to sand immediately before applying paint?
I’m not sure what you mean by licensed undercoat. You have not said the hull material either. Assuming the surface is sound, primed and you are now at a completely fair and filled surface having just completed the undercoating you will have already been constantly sanding between coats to gain a very smooth ripple free surface. It is not required to sand immediately before in order to top-coat but that also depends on how long since you last touched the hull, there may be overspray or other reasons to give the hull a quick once over before finish coats are applied. You would use clean lint free rags and a little solvent (not a soaking, there is not much point in washing off the last few coats!!) – enough for vapours in the cloth is fine. Water is fine (and is a solvent too – very gentle and always safe on a sealed surface) but should be all gone before the next finish coat. Metho may help with this but again use sparingly.
I’m not sure what you mean by licensed undercoat. You have not said the hull material either. Assuming the surface is sound, primed and you are now at a completely fair and filled surface having just completed the undercoating you will have already been constantly sanding between coats to gain a very smooth ripple free surface. It is not required to sand immediately before in order to top-coat but that also depends on how long since you last touched the hull, there may be overspray or other reasons to give the hull a quick once over before finish coats are applied. You would use clean lint free rags and a little solvent (not a soaking, there is not much point in washing off the last few coats!!) – enough for vapours in the cloth is fine. Water is fine (and is a solvent too – very gentle and always safe on a sealed surface) but should be all gone before the next finish coat. Metho may help with this but again use sparingly. Tack cloths are important just before coating application to fi
