Thanks to those who replied to my plea for help on filling. Some observations
and further comment on these are as follows:
1.I couldn`t see what was wrong with applying the filler dry (and light) other
than it`s a pig to get on and it takes ages (weeks) to cure.I think I may
persevere with the dry stuff at least on the counterbalanced surfaces; my
patience will probably expire sometime during the wings.
2.The Swinden fishing-line technique doesn`t work with dry filler.
3.Warm resin, as suggested in one of the replies, is beneficial in aiding the
mixing and spreading of a dry mix. To extend this, microwaving the mixed filler
for about 15 seconds I have found to be worthwhile (longer heating results in
resin gelling before application,damage to Expancel or exotherm).
4.I have found that the filler needs to persuaded to stick to the layup rather
than the spatula. To this end I have tried Teflon coated tools (didn`t really
work). Plain steel tools seem the best (its the same for puttying windows), but
has anyone else found a magic solution?
5.The persuasion process can be aided by coating the layup with a very thin coat
of pure epoxy (rubbed on with a rag, rather in the manner of French polishing)
and letting this go tacky. Timing is critical however.
6.Europa`s Q-cel (and not anyone elses) is excellent in addition to colloidal
silica in promoting thixotropy; something to do with improving the particle size
distribution of the solids.Expancel and fume together produce a `gap graded`
product.
Sorry to go on at length. Any wheezes anyone has come up with would be most
appreciated.
Regards, no 175
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