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[email protected] mike.e.worrall@abc.com is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 89
Default Fiberglass and Print-Thru

The term 'print through' generally refers to the coarse woven-roving
fabric used in a hull lamination lay-up being visible on the outside
of the hull. This is why - when hand laminating a hull - a layer of
mat is laid first into the gel-coat; the mat 'hides' the weave of the
subsequent woven fabric.

In a chopper gun lay-up, where a slurry of chopped fibers is 'sprayed'
onto the gel-coat, any "holidays" by the operator might allow the
woven fabric to 'print-through' , meaning that on close inspection of
the finished hull you'd see a 'small waffle' pattern in the finish.

Dark coloroed hulls do require a higher level of finish that do light
(white) hulls. This has something to do with the mechanics of our
eyes ( a subject way beyond my ken). Anyway, if you're going to paint
her, a dark color shouldn't be a problem, even *if* your hull has
print-through (which it may not - one can see print-through even on
white hulls with careful inspection) PROVIDED you can commit to
thorough preparation of the hull surface.

If your Sweetheart really wants to shine, the best choice is a two
part LPU, the final finish of which has been preceded with filling /
fairing and a couple of coats of epoxy primer.

This may sound daunting, but isn't too bad. Interlux has a cool on-
line video that shows the whole process for thier 'Perfection'
product, generally applicable to Awlgrip, etc.

MW