On the advice of several paint shops I took great care to avoid contaminating the primer.  They made the point that oil or any other contamination is a painter’s nightmare.  It probably would have been more than a bad dream in my case with oil covering the belly and going completely up the rudder and vertical fin several times at 40 hours TT (belly photo was one trip around the pattern.)   Luckily, I took extreme measures to keep everything clean prior to paint by wrapping the fuselage and wings with 18” packaging shrink wrap (trailer photo) for the trip to the paint shop.  I had 3 to 5 coats of block sanded WLS Filler Primer on top of the micro with many hours invested that I wanted to protect.  As far as removing oil from a primed, microed, composite surface, I would think shooting a protective coating (type and brand preapproved by your painter) would be cheap insurance against decontamination labor and future paint problems.

 

I had next to no clearance or rework issues after paint, interior and then first flight.  I might emphasize the minimum clearances prior to color coats should be a loose tongue depressor thickness or a little more depending on how thick the finish is.   

 

Steve Colwell Legacy

 

 

“ I have been told that if oil got onto primer it was impossible to remove. It makes sense to me but am I wrong?

 

  Although it's a long way off, my plan is to prime and then shoot a plain white top coat just to protect the primer. I paint outdoors so between the bugs, pollen, and my limited ability it won't be pretty but should last through test flights and any tweaking. By that time the flaws that were mentioned will hopefully show up and it can go to a paint shop for the final paint job.”