Bonding End Grain Balsa to hull sides

[bradz]

Hi everyone
Im slooooowly working through my rebuild and am getting to the point of reinforcing the sides of the hull.
My boat is a 19 foot Regent Viscount (West Australian runabout). The sides of the hull are quite thin and deflect quite a lot without too much pressure. In order to stiffen up the hull I am going to laminate some 1/2 inch end core balsa. How should I do this? I'm using polyester resin and was simply going to bed the balsa in peanut butter and then cover with 1.5oz CSM. Would this be OK or do I need a layer of CSM on the bare hull first?
Cheers in advance.
Brad

 

[Scott Danforth]

Look into core bonding compound

 

[ondarvr]

Sounds like an expensive and hassle filled way to solve a problem that may not exist.

How old is the boat, it has survived as is for that long. Hull sides don't need to be very thick, most of the time they're stiffened to appear strong, not be stronger.

Don't use balsa, it will rot, 1.5 oz CSM on the back side isn't enough.

 

[bradz]

I will look into the core bonding compound

The boat is nearly 40 years old. Its a good design but acknowledged to be a little light in the laminate.
Why would the balsa rot? It is above the waterline, on a vertical plane and has no through hulls, and will be covered in fibreglass.
The reason I am heading in this direction is to take the pounding in the bow area of the hull as we have very rough water where I do my fishing and really have to get the nose down to make any headway. I may even extend it to the main cockpit sides if I feel inspired.
.
It may seem strange, but my fibreglass supplier suggested I simply use thickened epoxy resin to glue the balsa even though I intend laminating with polyester. She said that as long as the epoxy is only used on the bonding surface then realistically there will be minimal (if any) areas where the poly with need to contact the epoxy...just on the glue lines. Actually sounds like a reasonable response to me. What do you guys think?

 

[ondarvr]

Everything in a boat gets wet, and the balsa will too.

To stiffen it you rely on the laminate on the backside of the core, CSM has virtually no strength, and at that thickness won't be waterproof.

As you stiffen the hull it will pound more, or at least feel that way.

If you are actually worried about the strength, add a layer of 1708 or 2408

 

[Baylinerchuck]

+1 on everything in a boat gets wet.

 

[bradz]

Hmmm. Even more to think about now. Thanks guys.

 

[djrowe007]

Hot day, cool boat, cooler in water, moisture is created. Eventually leading to rot. This would take some time though............