Posted for MikeEasley@aol.com:

 Scott,
 
 Micro is really hard to feather out flat over the softer primer or even the
 wing skin.  I tried and it never was really straight.  Every batch of  micro
 has a different hardness so they sand differently.  I ended up using  micro
to
 get it close and used some lightweight body filler for the last little  bit,
 never more than maybe 1/32" thick.  So the micro gets the shape, the  body
 filler blends the micro to the skin, and the primer gets it very  straight.
 
 I always wet out the wing surface before applying the micro.  I  painted the
 pure epoxy beyond the micro fill area by a few inches to create a  barrier to
 protect the wing skin.  Thick micro is really hard to spread  thin and
feather
 over the low area.  Thin micro is easy to spread but a  pain to sand.  I
 mixed the micro really dry, so dry that it was  almost impossible to spread.
 I
 held a heat gun in one had and the spreader  in the other, warmed up the
micro
 so it would spread.  [another trick is to cover the micro with a sheet of peel ply before smoothing... it keeps the micro from being dragged around when you trowel it.]
 
 The WLS tends to dry with a semi-glossy surface.  Even after sanding,  it's
 still glossy in the low areas that you want to fill.  I took a piece  of 80
 grit and roughed up the remaining glossy areas before using filler or micro.
 
 I would say that I finally got relatively good at body work about the time I
 was done!
 
 Mike Easley
 Colorado Springs