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Painting & Decorating Question
Do i need to sand between undercoat layers to secure a key?
I have always sanded between layers of oil based paint, three times in total, once after priming, in between undercoats and then finally ready for gloss. However I have recently been told this is not necessary and I'm wasting my time? I thought you had to do this in order to form a key for the paint to bond. Also at what stage would you apply decorators caulk as this cannot be sanded.
Normal undercoat is formulated to bond to existing paint and to provide a key to accept the finishing coat..the main point in fine sanding is to remove nibs and provide a smooth finish
Answered 14th Oct 2013
Once you have prepared the area I would then undercoat, and give it a light sanding with a fine grade paper to get a good bond for the gloss to stick to. This way you will get a first class finish.
Answered 18th Sep 2013