I am in the process of repairing airline cracks in the gelcoat of my beneteau 1986 while I was stripping the old antifouling paint I noticed some hard gelcoat bumps in the gelcoat, these little bumps are hard not soft, also when sanded they disapear completely blending in the gelcoat, any one have an idea of what they are, could it be that the mold was dirty when they gelcoated the boat, Any help would be appreciated John