>>Is the weight due to the
luxurious fit or is this likely to be a typical kit weight.<<
Hard to say. G-ELSA weighed 796 lbs and that included about 30 lbs of extra
engine.
Weight control is the big problem for homebuilders, especially composite.
You could start with Burt Rutan's first practice layup. This is a 6 ply layup of
BID, roughly 12.5" by 18". Do the layup flat on a waxed flat surface, squeegee
out all excess resin but make sure you don't suck in air, (white areas). A big
rubber sqeegee is best. (Aircraft Spruce sell them).
After cure cut to 10" by 16" and weigh. It should be no less than 10.5 oz. or
more than 11.5. Whatever that is in grams. A perfect test piece at 11 oz will
give you a guide to what the surface should look like. If for example your
layups were 12.5 oz, that would add up to 40 lbs extra weight on the finished
aircraft.
You must start controlling weight from the start, make sure the cores are
perfect before starting to skin them. That reduces filling requirement. When
filling don't rely on spray hi build filler to make up for imperfections.
Microlite filler is lighter, much ,than spray filler. Don't add that extra bit
for strength. It will only be needed if the plane is heavy, self fulfilling
prophesy!
Europa have allegedly been collecting builder's weights for various parts.
Hopefully when Andy can get off the phone and do some work, he will be able to
give us some target weights.
Graham
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