We had full Wooden cabinets from 1961 that were unpainted, so we sanded and did numerous coats of primer simply to cover the knots and oil stains. Now I feel we could have used a knot blocking product. We also painted all the backs and interiors of drawers and insides http://bookmarkport.com/story4754798/how-much-you-need-to-expect-you-ll-pay-for-a-good-best-handheld-paint-sprayer-for-cabinets