Deck core material question??

[JohnC]

I am planning my deck build and I’m a bit confused about some of the core material options. I want light & strong (me and everyone else!) and there are a few ways to get there. My plans it to cut & dry-fit the core material then layup on a flat table. I would like to vacuum infuse but I’m a bit intimidated when I add the cost of core material, glass, epoxy!!! That’s a lot riding on one error free VI pull.

Single level deck for a 20ft SeaCraft is (4) – 4 x 8 sheets (I’m using 1” thick core).


Core options:

Divinycell H-80, 5# density foam; 4’ x 8’ x 1” sheets are $425
Corecell M80, 5# density foam; 4’ x 8’ x 1” sheets are $320
Nida-Core 5# density honeycomb; 4’ x 7’ x 1” sheets are $75
Coosa Bluewater 26# density foam; 4’ x 8’ x 1” sheets are $400

And for comparison!
Marine Grade A/B fir plywood (about 45# density); 4’ x 8’ x 1” sheets are $230


First question – what’s the difference between Divinycell and Corecell. Doeas the added cost for Divinyvell buy you anything?
I have heard that one is better in the South Florida sun than the other but I can’t find anything concrete to support this. I also can’t recall which is one more heat tolerant. Both manufactures state that their 5# core is suitable for decks, fatigue areas, etc. If I decide to VI my deck it will be one of these cores.

Second question – Is there an advantage/disadvantage with honeycomb over the foam cores. Nida-Core is not suitable for VI but if I do a hand layup, it’s an option that would save about $900+. The weight isn’t really any different according to the PDS.

Regardless of what I use I plan to buy 1 sheet of Bluewater 26 to use in the areas under the console & leaning post & around the bilge hatch. Nothing would be screwed to or thru-bolted to a low density foam or honeycomb deck.

Long winded I know!!!