[Public-List] What is the ballast bedded in?

[Adam Quenneville]

Hi all,

Hull #581 here. 1975.

The fiberglass covering the ballast was compromised and leaking. It had 
been repaired previously but unfortunately the bond did not hold. I've 
removed the fiberglass and exposed the ballast/keel cavity.

The iron ballast is set in some type of sandy compound, which is wet 
with water and some oil. It almost seems like a clay and sand mix, but 
from what I've heard about other boats, some times vermiculite was used. 
I have come across a lot of vermiculite in my life, and none of it 
looked like what surrounds my ballast.

Does anyone know with certainty what was used to bed/set the ballast in 
the keel cavity in Alberg 30s?

I ask because the bedding compound (if we can call it that) is about 1" 
below the top of the ballast. I would like to fill it flush before 
fibreglassing over it.

If a direct replacement isn't available, can anyone suggest an 
alternative material? Either foam of topping/sand mix crossed my mind.

Many thanks,

Adam