Pete,
Sounds like an 'epoxy starved' area, to me. Either not enough epoxy
UNIFORMLY applied to begin with, or an area rolled/squeegeed to hard and the
epoxy pushed away. To avoid this I usually apply in 2 to 3 'steps . . .
a} with raw wood - I put on a coat of unthickened epoxy and let it cure . .
.. then cut parts. b}With repairs or applying cloth to a hull . . . apply a
coat of unthickened epoxy and allow it to 'set' - from just when it looses
it's tackiness, to the 'green' stage.
c}Lay out the cloth/tape . . holding it in place with 'thumb pins' or
masking tape, and apply epoxy mixed with a bit of fumed silica as a
thixotopic agent - more then a little if it will be painted or I don't need
a Clear finish.

Regards,
Ron Magen
Backyard Boatshop

"(PeteCresswell)" wrote in message
...
Just finished applying about 40 feet of 1" fiberglass tape to a surf ski's
(long, skinny sit-on-top kayak...) hull/deck seam using West System epoxy
resin.

99" of it went as expected, but I've got a few areas (2" max) where the
resin/tape is milky white. In the longest area, it was uniform from one
edge
of the tape to the other. In the smaller areas it doesn't extend the
full
width of the tape.

I guess I'm going to grind it off once it's cured and try another layer,
but the suspected cause will determine how I go about applying subsequent
layers.

Water weeping from the seam? Contaminated tape?

Something else?
--
PeteCresswell