Make your own blade - Is marine Epoxy the best ?

Once I was bitching about core made out of mutlple pieces to save on wood, I thought there was value in one piece cores. I later learned that wood glues create a bond that is stronger than the bond between 2 wood cells so 1 piece core is just luxury, not an actual factor in performance. 

If wood glues are that strong, there is no need to get epoxy for all wood blades since it's more expensive and harder to work with. For composite blades, we can't avoid epoxy.

The clamp you are talking about is the clicky press, not good for blade building because it does not cover the handle. Heavy books will work to learn and have fun experimeting, you can always buy something better if it becomes a serious thing. 

Searching for "clamp veneer" gives interesting results. That could be an interesting sledgehammer blade to play at 7m55s  https://youtu.be/dVJ9feaGN5U?t=475 Maybe an overkill ? 

Ross Leidy uses a vacuum press to glue wood veneers with epoxy, it is the absolute best way if money is not an issue.

I don't know anything about Marine epoxy but made my first blade with 30 minute Bob Smith Epoxy and cut notches in a popsicle stick to trowel it on and clamped it between two boards with a bunch of hand clamps.  It was 3 mm Paulownia core, 0.5 mm carbon (ready made), and Koto veneer.  Basically it has two to four layers of uneccessary epoxy, since the epoxy used to form the carbon fiber is all the glue you need if you buy unimpregnated carbon and build yourself a vacuum press.

The best core for strength to weight ratio is endgrain balsa, but it can be pricey to order or dicey to make your own as one of the chunks of balsa I ordered was noticably heavier.

My next blade planned will be a Balsa end grain core that I made by gluing three balsa chunks together and running it through a band saw.  I will seal it with an epoxy/Caboseal mixture with exess wiped off with paper towel and vacuum press it with a peel ply layer to wick up more epoxy.  I'll then place two carbon fiber sheets between plastic and use a plastic squeegee to spread all exess to the edges which I'll cut off and then sandwich them (slightly offset left and right so there are fibers running in every direction) between the core and a cedar veneer under a vacuum press and roll out the air bubbles with a Kutchen roller once the vacuum is on.  I will use 1/4" glass for the base with tacky tape sealing the sheet plastic top.  The vacuum will be the intake of my air compressor using a negative pressure gauge to monitor for leakage when under pressure and I close the shut off valve and turn off the compressor.  My biggest concern is that 30 minute epoxy is not enough working time, but the hour epoxy is real pricey.

The reason for all this is that I want a much longer than normal paddle; otherwise it's hardly worth all the effort.