Thanks for all the replies, guys.

I don't think that there is any problem with the compatability of the paints and primers as I have been using these same and wide array of paints over and under each other for many years on all sorts of planes and other projects with no problems other than the occasional laquer over enamel too heavy, too soon.[X(] It has only been on the RC projects where I've been moving into greater detailing and the creation of relieved panel lines using the chart tape and the much thicker builds of primer used to accomplish that.

I have cut away one of the blisters and it is definitely the primer separating from the resin. I have noted however, that it only seems to occur in areas where there has been a high build of primer....namely, just as in the photo above, near a panel line or especially in the middle of a smaller panel section.

I'm leaning toward the explanation that the primer is not being allowed to dry/cure enough between coats. On the two recent problem projects I have used "Dupli-Color" filler/high build formula automotive primer and "Dupli-Color" sandable automotive primer as well as Rustoleum "ultimate finish" laquer type primer.

Application has been as follows after glassing, assuming the temps and humidity are favorable;

1. give the glassing medium of choice a good rub down with 380 grit. from now on I don't handle the parts with out surgical gloves or a towel and I'm very mindful of drops of sweat.
2. wipe down with denatured alchohol or acetone immediately before 1st primer to remove all of my skin oils and sweat from the surface. Wipe down with a fresh, clean cloth.
3. light coat of regular primer grey with a light coat of brown on top.
4. light sand to reveal surface dips-all brown and most of grey removed removed except in low spots.
5. putty the deeper dips and allow primer to fill the shallower stuff.
6. continue grey/brown coats and putty 3-5 times til satisfied with surface. 380 and 400 grits. at this point there is only primer or putty in the low spots and the rest of the surface is back down to/not through the resin.

7a. On many past projects this is where a light primer/finish sanding followed by color coat and fuel proofing would be applied with no subsequent problems with regard to paint. The projects which have presented problems have the following difference:

7b. forego finish sanding for now and apply chart tape
8. med/heavy application of high build filler primer over tape lines
9. 1-2 hours hit it again or as soon as it won't cause the previous layer to orange peel or run.
10. 3-4 more heavy coats as quickly as I can get them on without souring the underlying coats.
11. next day it's usually dry enough to wet sand. by the time the sanding is complete the top, clear layer of the chart tape has been more or less removed and the wood grain is becoming visible in the areas where there is a large expanse between the tape lines. most of the primer has been removed again, except at the chart tape.
12. dry everything off, wipe it down, hit it with the air hose and hang it up by wires.
13. when I'm sure water contamination is no longer a factor I hit everything with a couple light coats of regular primer and some finish sanding. 400 and 600 grit.
14. last coat of dark grey primer, just enough to be uniform and cover.
15. 3-4 hours later fish sand wet @ 800 grit followed by a few light coats and a couple medium coats of "10 minute dry time" silver as the base for the rest of the color coats.

14 and 15 are the same as 7a and have been fine in the past.
It's the addition of 7b-13 that I know are the problem. I think maybe I'm not giving the high build primer enough time to fully "off gas" and cure before I'm locking the still wet solvents in with the quick dry color coat. Then even 3-5 weeks later some areas blister in the sun.

Or is there something else that may be in the proceedure on top of insufficient time between heavy prime coats as well as insufficient time for the primer overall?

What do ya'll think?

Thanks again.