you can use poly(fiberglass) resin but that stinks and has nasty fumes, so a lot of peopl use epoxy resin but it`s a bit more expensive(here in the UK) i`m not 100% sure on the water soluble wood glue, the wood glue i use is water resistant, im using it on my balsa airboat build, and then using epoxy resin, to seal the wood and make a harder surface for the soft balsa, its alredy got dents and i aint finished building [
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