Hi Jack / All,
Filling with a ''comb'' works well on large surfaces like boats [ I was
doing that with Polyester resin / Phenolic spheres on 25 '+ boats back in the
'
70's] where the weight is not that critical, but of no real use on our planes.
If the Expancell / Epoxy is mixed runny enough to be combed on, it will be
too heavy, and much harder to sand.The Expancell mix should be almost like
bread dough to put on.... a real bugger to put on.... and impossible to get on
smoothly / thin. As mentioned before on here, fill too proud ONCE, it will sand
like dense balsa.... if you have to go back for a second fill you may end up
with different densities... which as Graham mentioned, will sand away at
different rates. If you managed to comb it on, you will end up with stripes, if
you have to fill an area, you will get a ''tide mark''.
Those of you useing Superfil may get it on OK, because that is runnier /
heavier / more difficult to sand than correctly mixed Expancell / Epoxy.[ Why oh
why do people insist on useing that ?]
Other problems [ with Epoxy] is that all the ''valleys'' that did not
get sanded during the profiling, will have to be scuff sanded, to remove the
top surface [in preparation for adhesion] before a second fill can be
applied,probably have to scrape it all with an Xacto blade, rather negates the
point
of only sanding the '' hills''?
No short cuts in this world I'm afraid ?
Cheers,
Nev.
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