Exactly right Wayne!

Some Polyester and Gelcoat sold for car and boat repairs in hardware stores
contains wax, but commercial gelcoat used in moulds and polyester resin used
for laminating does not. For a proper cure, polyester must be shielded from
the air and the wax floats to the surface and inhibits reactions with the
air. Applying wax paper or plastic film over small repairs allows wax free
gelcoat/resin to cure hard.

Epoxy resins do NOT contain wax and do not need it! But, poor quality
epoxies do "blush" - this is a wax-like material that forms on the surface -
It is not wax, but is formed by a reaction between amines in the hardener
and water and carbon dioxide in the air to form an amine carbonate. This is
not a problem when laminating, but if the epoxy is allowed to fully cure,
this product must be scrubbed or sanded off before applying more epoxy or
paint.


"Wayne.B" wrote in message
...
On 24 Aug 2006 21:24:02 -0500, Dave wrote:

Epoxies must be sealed off
from air exposure in order to cure.

That is not true, you are thinking of polyester resin, not epoxy.

They are not the same.