[Public-List] Reinforcing the cockpit sole

[Gordon Laco]

Hello George and Stephen -

I did a cockpit core job in SURPRISE a few years ago.  It was a two day job,
and not at all as difficult as I thought.

I cut the top skin off, scrapped out the rotten balsa and the good too....
Laid in a paste of thickened epoxy then laid a new plywood core.  I drilled
a 'ton' of 1" diameter holes in the plywood.  I put bricks on wax paper on
top of the plywood, then started pouring epoxy in until no more would go
down.  (the bricks are so the plywood couldn't float)

Next morning I epoxy into any visible dents or voids in what I'd done the
day before, then covered the whole thing with more thickened epoxy.  Down
onto that went the old tip skin, with the bricks on top so it wouldn't
float.  I troweled thickened epoxy into the kerf.

Later, I sanded and painted the cockpit sole.  I expect I may get tiny
stress cracks around the edges of the section I cut out and replaced... But
it's a simple job to paint them again.

Gord #426 Surprise


On 24/02/14 5:12 PM, "George Dinwiddie" <gdinwiddie at alberg30.org> wrote:

> Stephen
> 
> On 2/24/14, 3:46 PM, Stephen Gwyn wrote:
>> 
>> Hi George,
>> 
>> Yes, the cardboard V (or U, or ideally some sort of square shape)
>> glassed over is exactly what I had in mind. I've also heard of foam
>> shapes used, instead of cardboard.
>> 
>> What I was looking from from the group is whether anybody has actually
>> done this under and Alberg 30 cockpit sole, and if so, what special
>> techniques they used to glass to the bottom of a surface in cramped
>> quarters.
> 
> I've not done it, but I can tell you it will be hard to do. Perhaps if
> you removed the plywood bulkhead to one of the side lockers and worked
> from there you could reach OK. Be sure to put down plastic sheeting to
> catch the drips and keep them off the engine and shaft.
> 
>> Alternatively, one could imagine a few solid oak beams under the
>> sole. Or even aluminum angle stock, or an I beam extrusion. One could
>> steal a section of toe rail off a C&C for example...
> 
> How would you fasten those? I wouldn't want to add holes. And the oak
> would eventually rot.
> 
> I redid my cockpit sole, but that was because the core was rotting in
> the aft area due to water intrusion around the rudder post. Whitby just
> cut a jagged hole there, and left balsa sticking out to catch any water
> that seeped under the rudder post fitting. ;-) If you've got that, I
> suggest trimming the balsa and sealing the edge with epoxy.
> 
> I cut out the upper laminate, dug out the core (some of which was the
> consistency of toothpaste), put in foam core, and laid up new glass on
> top. The sole is pretty rigid now, but that doesn't mean there's no flex
> around the edges. A box is not an inherently stable shape.
> 
>   - George



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