Re: Going foamless
hi....got asked to look in on this.....
ok....so you are going to place foam in the outer stringers.......right?.....then glass over foam ?
this means your intent is to use the glass as a stringer....(foam it self will not do any thing)
you can do it that way, but you will need a barrier between the foam and the resin.....the resin will eat the foam.. plus...as the foam expands, you will need to find a way to contour the shape to what you need.
if you start messing with the foam during expansion, you will be breaking the bubbles and loosing all structure to the foam) fairing the foam after to achieve structure will be inconsistent, and again, allwoing the bubbles to be broken, thus allowing water logging.
and unless there is heavy carp in the channel, you wont need to sand it.....just clean it so the foam grabs the hull and the stringer sides.
but i foresee a few problems........your stringer height is crucial.....this will be your deck support......expanding foam has no limits,,,,so the height will vary....and you cant compromise on the thickness of the glass over the foam.
if you ground out those channels and used a cardboard tube.....then you would have correct height, and shape....the foam could be injected later, or before the glass wrap.
free floating your deck is not a great idea.......the hull will flex in the middle of the boat, leaving the tabbing as your contact points....this will crate stress in the tabbing area and crazing of the outer gellcoat could occur.
even a few points to screw the deck down would be good.....it would also stiffen your hull.
you mentioned in your first post that you wanted to leave the centre channel free of foam but you only saw 2 layers of roving as hull.
where ever the foam was, that you do not want it to be, needs to be strengthened with 2 layers of 1708 and csm between the sub straight and between the layers.
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