laminating - air pockets?

[ElBichoMalo]

John,

I wasn't trying to knock you, and I don't think you took it that way. Yes, I am talking about Polyester Laminating Resin, so no blushing. John, since we are talking poly, not epoxy, does that mean I can let each layer cure out and still not sand before the next one?

[JohnB]

I didn't take it as a knock, I just wanted to make sure what materials your using.

IMHO, if your doing layers within 24 hours you don't need to sand. What I do is take a grinder or small roto grinder, and knock any of the high spots or strands back, since they stick up, and cause an air pocket in the next layer. That is something you don't have to deal with when hot coating. Generally, I will rough the surface up with the grinder, just the high tops, not grind into the fabric between coats.

I wasn't trying to make a federal case about it, and putting down 2 layers at a time saves time and resin. I tend to make the first layer a little less hot with the catalyst, and then make the second layer standard ratio. I try to do it when it is under 70 degree, and in the shade, and have less problems.

[gofastsandman]

Hey EBM,
John makes god points. I used glue products stuff but u s composites is cheaper price wise. They answered many of my questions. I`m in so fl and they said not to hot coat down here. 80 deg in dec. Sand in between coats to get good "tooth" and wipe w/ acetone to get dust and break the skin for a good bond and it will soften the layer too. George at g&s told me to flash coat the plywood core for better sealing and bond. To flash coat , mix the resin and mek and then cut w/ acetone to consistency of water for deep sealing and bonding. Don`t know if that applies to composites or not. Don`t forget the surfacing wax for the last coat. wear tye dye as you`ll be back in the 70`s in no time.
GFS