XPS FOAM to replace stringers

Caribenio

Cadet
Joined
Jun 6, 2019
Messages
11
I discovered a couple of soft spots on the floor of my boat. I will investigate after the summer what’s the extent of the damage. I hope to see just a partially fix of the stringers but I want to prepare for the worst.

While looking at DIY ways to replace all the stringer in my boat I saw that some people have done it with XPS FOAM.
Does any body here knows anything about that?
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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Jul 23, 2011
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50,316
if your floor is soft, your transom, stringers and bulkheads have already rotted. boats rot from the drain plug up.

read all the links in the DIY stickies, start with link 14, and watch all the videos, etc.
 

tpenfield

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Jul 18, 2011
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Extruded PolyStyrene (XPS) sheets would require you to use epoxy resin rather than polyester resin. Not a big deal in itself, but a bit more costly and you will want to stay with epoxy for the balance of the repair. Polyester resin will not readily adhere to epoxy resin.

Additionally, you will want to use about 4X the amount of fiberglass than with wood stringers, because 95+ % of the strength of the stringer will need to come from the fiberglass if you use XPS boards . . . unlike wood stringers which have their own strength.
 

Caribenio

Cadet
Joined
Jun 6, 2019
Messages
11
You just burst my bubble of hope!! LOL well, I may just sell it of a few bucks and save money for a nice boat. Although we really like this boat. Let’s see.
 

jbcurt00

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Oct 25, 2011
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You can also wrap the foam w packing tape really well so the polyester resin never comes into contact w your foam. But yep, you'll need more glass....
 
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