Couple things, Steve. I thought that post-curing is largely
ineffective unless done within a couple weeks of a room-temperature
cure. Thus it applies only to the few such surfaces required of
current XS kits. Has the Europa manual guidance in this regard
changed?
The Smooth Prime is a flat finish, aka porous, especially after
sanding. The more delay between application and finish coating is
more time for contaminants to accumulate in the surface that cleaners
will not completely remove. The Sherwin-Williams web site has an
excellent document with color pics, discussing all the bad things that
then result. The way around this I'm using is to omit final prime
coats until ready to finish coat. Cleaning, sanding, and final
priming hopefully will minimize the problem.
I wouldn't be concerned over aging or "stressing" the primer for any
particular advantage. There can be problems with certain solvent
based coatings, if the stuff is too fresh or not two-part, but neither
System III nor PolyFiber advise caution for their water-reducible
products. As S-W implies in their doc, the causes of coating problems
are often anything but intuitive for us novices.
See www.sherwin-automotive.com/reference/troubleshooting_guide/
Regards,
Fred F., A063
> Steve Hagar wrote:
>
> I have been eager to get my fuselage into the garage since all of
> the flying surfaces are complete and the lids are glued on the the
> wings. However I have decided to hold short for awhile. I had
> picked up one of those small palm sanders and put in some hours with
> it and super fill and was impressed on how smooth I was able to get
> some of the joints and imperfections.
>
> My plans are to spend time to go with the poly fiber UV smooth prime
> route and to take whatever time it takes to get everything coated
> and smoothed out. I haven't started yet but my plan of attack is to
> roll on three coates as noted in the instruction book and then use
> the HVLP sprayer to get the close out ends of the flight controls
> and other areas inaccessable to the rollers. Then continue to give
> the final coats with the sprayer instead of the roller. Then sand,
> sand, sand. The results will then be stored for many months (years?)
> Until ready to be complted with the final aircraft finishing. Then
> my thoughts are to take this whole mess into the back yard during
> the middle of the Arizona summer. I would then weld me up a light
> frame to drape black heavy duty plastic around to make a large oven
> of sorts. This would be my post curing cycle using the sun to do the
> job. I would think that this would also stress the UV smooth prime
> to an ex! ! ! tent that it will do its shrinking, cracking, or
> whatever then, rather than after the paint gets sprayed.
>
> I would like to hear any "been there done that" or "watch out for
> this" stories or tips that any of you may have out there. I noted
> that recently Tony had issue with making sure of a full smooth
> prime cure before final painting. This routine should more than
> cover any concern of that nature.
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