A further refinement of Graham's clingfilm technique for TE
closeouts (also works well for control surface leading edges); this comes
originally from Mike Arnold's excellent "AR-5 Tapes:"
Cut your bid a bit larger than the final dimension, put it down
on your table atop a considerably oversize piece of plastic (clingfilm
works OK but I use
heavier plastic sheeting because I find it easier to work with). Dump on
the resin any old how, and repeat as necessary if additional plies are
required.
Now--and this is the beauty part--cover the whole oozing,
wretched mess with _another_ sheet of plastic and, with your trusty
squeegee, get everything nicely wet out and all the excess resin herded
away, well off to the sides beyond the edges of the (still oversize at
this point) bid.
Next, with a felt marker, mark off the correct dimensions on the
top piece of plastic and trim to size with your "wet" scissors. The
resulting "sandwich" is dimensionally accurate, nonsticky except at its
edges, and easy to carry about. When ready to put it into position, just
peel off _one side_ of the plastic, put it in place, squeegee lightly
through the remaining plastic, then peel that one off. Glass/resin ratio
should be just about right already; at worst you may have to to a bit of
light squeegeeing or stippling to get the occasional air bubble out.
BTW, for something like a control leading edge layup that
requires hinge reinforcements between the layers, I've had good luck
doing a single plastic sandwich big enough for all the separate pieces,
then cutting them out one at a time and putting them onto the part.
Still much easier than writhing Laocoon-like amidst clinging serpents of
unstable wet bid (ah, the vestiges of a long-lost classical education!).
Peter Lert, US 37
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