Heavy glass? New board feels heavy

Just glassed my first board. It came out…medium but I’m happy with it.

One thing I did notice was that the board, a 5’8” fish came out heavier that I thought. Any obvious reason I missed. Here’s my schedule:

1 layer 4oz cloth on the bottom
2 layers of 4 oz cloth on the top
Bottom lam resin was 20 oz
Top lam resin 24 oz.
Hot coat is 18 oz of resin both sides

Am I using too much resin, can figure it out. Shape is super close to other professional boards

There is a lot youre not saying, or showing.

What blank did you use? What did the shaped board weigh before lglassing? What does it weigh now? What were you expecting it to weigh? What resin did you use?

No pics of the laminating or fill coat, no pics of the finished board, no pics of anything.

The thread title is Heavy glass but fiberglass eloth weighs very little. Maybe youre using too much resin, but hard to say without good pics. The laminating coat should be just enough to wet out, but not pool. No floating fiberglass. You should be able to just see a slight pattern of the weave, then the fill coat or hot coat will fill that in.

Glassing is not hard to do, but its hard to learn to do it well. It takes some patience, persistence, and practice. You glassed your first board, you’re on the way!

I’ve shaped and glassed a few dozen boards, and my glassing is passable but not best in the show. Lotsa respect for those guys who turn out showroom quality boards and make it look easy.


I think it’s how much resin is left in the glass. I tend to laminate on the dryer side.
I probably use less than 20 ounces of resin for an 8’ board and double 6oz glass. But I follow up with a coat of 4 to 6 ounces about an hour later. Using epoxy resin. Somewhere I saw somewhere that the strongest fiberglass/resin mix is 1 to 1, but I could be off. That ratio is almost impossible to do by hand if you are not very experienced.
I redid a board glassed by one of the top glassers here on Oahu in the 90s. I found almost 1/16" of resin under the glass in some places. I didn’t expect that.
A friend of mine who glasses his boards himself said that with Poly resin you need to glass fast. Keep the resin mix cure time short or the board gets heavier. I also saw a clip online that showed a British guy glassing, and he lets the resin soak into the foam a minute before he pulls it all off. But he used 3 times more resin than I do and quite a bit of it ended up as waste. I try to only use as much resin as it takes to fully saturate without waste, and I have had times where I needed to mix up a couple more ounces to get the laps saturated. Not the way industry guys do it, but I only make boards for myself.
I can see why good glassers charge what they do, they use a lot of resin to get perfect results.

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Unless you are using some crazy dense blank, my guess is it’s resin. The lamination instructions above are great. I bet the issue you ran into isn’t the lam but the follow up fill/sand/finish coats. In those coats it’s less about how much you put on and more about how much you sand off. I try and sand my fill coats to where the board is perfectly flat/smooth and I’m just barely seeing/touching the glass in the flat areas. Then when I put my final coat of resin on I spread it smooth and thin and don’t have to sand too much.


Fill coats and hot coats will add weight significantly. Cut lap free lap ? Which did you do. Also the fin system your using. Glass ons ? Future?