- - Definitely do not use expandable foam. Both UV and/or just high temperatures will cause shrinking and degradation. You mast
will be flopping around in a year or two or less.
- - Spartite is 2-part RTV rubber at an extreme price
. You can purchase
pint/quart/gallon cans at WWW Grainger & Co in the USA. You will need a friend with a business to purchase
it as WWW Grainger is a wholesaler. The price
is a fraction of the Spartite price.
- - You install a "dam or barrier" underneath the deck
around the mast
. Then mix up the two part RTV rubber and pour it in the cavity around the mast.
- - RTV rubber is used to make molds for metal parts
in industry. It hardens but can be bent enough to extract the molded piece. As a mast wedge it works great. It can move a very little bit so that shock loads to the mast don't buckle the cabin
top. I installed it around my two mast 10 years ago and it is still in good shape. However as the boat and mast flex it will loose it grip on the painted aluminum
mast and you will need a mast boot to keep water
from working down the surface of the masts and into the boat.