Peter Thomas asked:
<<As I was sanding I realised that at the leading edge there will be nothing but
fresh air to support the flox filler, as I will by then have cut the jig back
5cm. However, the layup at the leading edge has to wrap around by 2cm. I am
worried that it will be difficult to prevent the flox misforming at the leading
edge, resulting in a dint or bubble. I imagine the viscosity of the flox is
especially important at this stage. >>
I found that the viscocity of the flox is important, not too wet or it will
slump and move. Lay flox on slightly proud of joint and cover with microwave
cling film (does not stretch as readily as standard variety) then squeegee over
cling film to attain correct profile. Layup 2 layers of Uni cloth as per plans,
wet out and then check all is well with straight edge at joint area. If flox has
been disturbed chances are the joint area will be high, in which case it can be
pulled down level by carefully squeegeeing (is this really a word?)
perpendicular to the rib reinforcement. Keep checking undercut area every 1/2
hour or so until resin has firmed up to ensure nothing moves. A bump on flying
surface is bad news because:
1) The laminate must be flat to attain design strength
2) Lots of filler (excess weight) is needed to produce a level surface
PS I always spray peel ply with spraymount or photomount, which makes it self
adhesive and easier to work with, this will help greatly in holding the undercut
glasscloth in place.
Best Regards
Allan J Hall #177
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