Feedback on using styrene foam strip plank

[zigzag]

PVC foam core is expensive, Dow styrene insulation foam is cheap and available in 50mm.
If the one side face of a 50mm thick sheet was laminated with a lightweight chopped strand matt and the sheet was ripped to 18mm-20mm thick strips there would be a rib on one side that when the foam strips were edge glued into reverse flipped female hull moulds there would be a spine / web at each 50 mm plank joint.The single rib per pbonded seam would act as a thru bonding web/strip that would limit any debonding, once both sides were glassed over with unistrand fibreglass on the vertical axis with a light 10 oz WR over. All epoxy of course. The application would be for a lightweight tri centre hull of maximum 20' length
Re amas: has anyone used Hobie 17 hulls and would the 17' Hobie rig be approriate?
Comments appreciated.

[jimslade]

The sheer force on styrene panels is very low. I would advise against it. There are better tried and true options out there.

[nero]

Back three years, I laminated some high density extruded polystyren with some 10 biaxel and another sample with 8 mm Osage Orange. Laminates were on both sides of the 40 mm core.

Results were that the test strip did hold my weight (60 kg) over a 500 mm span. But it did bend a bit. The flexing is what will lead to delamination. When hit with a hammer, the glass/foam/glass didn't resist. I tried the same test with some corecell. Corecell didn't bend or compress near as much and resisted for a longer time before destruction from hammer blows.

I ended up strip planking with cypress with glass skins. Less costly solution for me at that time.