i’va made some board,during the sanding i’ve sanded a little bit too long or too hard,and now i can see the cloth,only the third layer,if i give to the board the finish spray anti UV ,the cloth is no more visible,so is correct to give the spray (i don’t think the water could pass inside the board ) or is not a good work,and i have to re-glossing every place where the cloth is visible?
You’re OK. Don’t sand so hard in one spot. Keep it moving and back off. If you are using an elactric sander; the weight of the sander and gravity is enough pressure. Keep it moving.