In the last communication I had with Poly Fiber some time ago, their tech
advisor was adamant that the Smooth Prime be covered with an epoxy primer to
seal it, and then move on to primer for the finish coat, then finish coat.
The UV Smooth Prime does not require Silver Shield because it has enough UV
blocker in it to do the job.   So my understanding of the sequence is:

1) Superfil for final shaping
2) Smooth prime to fill pin holes, sand smooth.  
3) Epoxy primer to seal the Smooth Prime and prep for finish
4) Finish coat, or finish primer and finish coat.  

Always make sure the finish coat and its primer are compatible.

It appears that the problem may arise from the failure to seal the Smooth
Prime with epoxy primer.   But look to the manufacturer for the final word,
since I am not a finish expert by any stretch.

Fred Moreno


Posted for "F. Erhald" <f.erhald@planet.nl>:

Gentlemen....
  
  My Lancair 0-235, which were scheduled to fly this spring, has got
blisters!
See photo.
  
  The aircraft was painted according to instructions made by Poly Fiber, Jon
Goldenbaum as follows:
  
  1) SuperFil to cover pin holes in the structure.
  2) Smooth Prime
  3) Silver Shield
  4) Smooth Prime
  5) Aero-Thane
  
  The aircraft has been hangared in an unheated hangar for the last two
years.
  The bubbles were not there one months ago.!
  Humidity has been high the last 2 months, but I never expected this to be
a
problem.
  By puncturing some bubbles water seems to appear.
  
  Have any of you encountered similar problems?
  
  Best regards
  
Fritz Erhald
  f.erhald@planet.nl