glassing - how to prevent it from taking water

could someone figure out how water is getting in - I have glassed about 7 boards with both epoxy and vinyl ester resins - polypropolyene and polystyrene foam blanks and everyone takes water on the very first outing. I use 2 layers of 4 oz. on both deck and bottom and do not see any holes or anywhere the water can be getting in and have even used pigments in the resin alternating colors to see that it is complete - how important is sanding between laminations , smootheness etc. ? Yet I buy a professional board that weighs less than mine complete that do not take any water. Does anyone know of the cheapest epoxy glassers in central east coast florida - say Brevard county ?

i guess the big question here is what is your lamination technique/experience? i’m not sure how you know your board is taking on water so fast. are you standing them up and water is pouring out? do you set them in the sun and little beads of water come out of the lam from the heat? if it’s the latter, take a close look at that area and see if you can tell what happened with the glass there. are you sanding too much on the bottom or edges and therefore exposing foam? as you can see, there’s a lot of variables. there’s probably an archive in here on glassing, check it out and see if you’re doing the same thing. also, you might want to check out john carper’s glassing 101, it’s very helpful. good luck.

There is no need to sand between the layers as long as you keep on glassing befor the layers set. Epoxy binds with epoxy when its cured too, but then wipe it clean befor laying up the next layer, epoxy gets a film somtimes on which you should not lay the next layer, if you do that it will delaminate showing in white batches between the layers. Blow off any dust from the blanks with compressed air before you start glassing. Then do the board in one run. 30minute open time epoxy is good if you are experienced, use slower hardener if you are working slower. try 2 layers 4glas on the deck and one 6glas on the underside this will save weight.