I pfaffed around with the final surface finish quite a bit and I have to say that it let the whole project down. But, at least now I have something concrete to get help with.
The bottom side came off the rocker table very slick with a great shine on it. There were a few small voids in it but not enough that I was worried about it letting water get in. The top side came out fairly dry of resin (at least that's how it looked). So, I thought that I do some final work on the surface finish on both sides to see if I could get a high quality finish.
I sanded the top side with 400 then 600 grit wet and dry and sanded the underside with just the 600 grit (to see if that roughness would have any impact of the lustre of the finish). It certainly did. The top looked milky. The bottom not nearly as much but the shine was definitely taken out of it.
I went bought some Gold Spa yacht varnish from Witworth Marine but the weekend staff were not particularly knowledgeable on the varnish but the convinced me to try alternative one that was a polyurethane varnish and is supposed to have better UV protection. Seemed to make sense. Problem was that the varnish was too viscous to get into the small voids and all it did is make them more pronounced. I tried it on a test piece first so it was no dramas but it meant that I decided to just put down a thin coat of epoxy.
I thought about thinning it out and in hindsight should have. Although it did give a very nice clear, shinny finish it did not self level very well (maybe because the FGI resin is relatively high viscosity?) and so it left an uneven surface that I am none the wiser about how to fix. In the picture of the underside at the bottom of the photo you can just make out some of the brush marks. A close inspection of the board shows a lot of these and it looks pretty ordinary. Chalk this up to experience.
So, I'll do a little googling around to find out more but I am officially calling this board finished and started to think about the changes I'll make next time round.
The biggest success out of all of this was the graphic inlay. Easy to apply, looks great and cheap ($25 per side)