Fred,
I talked to the smooth prime people and that is what they told me
about primer and top coat application. Even when using their top coat,
they wanted me to put on the epoxy primer first and then a top coat.
Believe me, I was getting tired of sanding and wanted to get it finished.
Yes, the wet-on-wet will increase the coating thickness and
subsequential weight. How long it will last----?? don't know.
Jim Nelson
<fillinger@ameritech.net> writes:
> James Nelson wrote:
> >
> > ...Smooth Prime says you must use the "paint mfg. primer
> > with their paint." If you use Polyfibers paint, you must
> > still use a primer on top of the smooth prime and then follow
> > up with a color coat.
>
> PolyFiber's paint book says you may use solvent-borne primers over
> smooth prime, but that it is "overkill." Has their advice changed?
> I
> can't see how they can imply that any brand of primer will adhere
> to
> Smooth Prime better than any brand of topcoat alone. Their
> water-borne coating competitor has contrary advice here.
>
> Besides weight, excess total coating thickness can be a real
> problem,
> and has happened to me. It's described in Sherwin-Williams'
> Troubleshooting Refinish Problems, under cracking and peeling. I
> noticed it especially on fiberglass parts of a metal airplane, as I
> suspect it may be the varying expansion coefficients in mixing
> finishing systems, especially on flexible surfaces like fiberglass.
>
> Further aggravated by frequent temp extremes. And especially with
> hard polyurethanes, which if hard don't stretch either, so in a few
> years it can just fall off if it doesn't do you a favor and merely
> crack. That's maybe why PolyFiber says their solvent poly is super
> flexible, appropriate for fiberglass too, and is applied over
> Smooth
> Prime.
>
> Regards,
> Fred F.
> N3EU
> The Europa Forum is supported by Aviators Network UK
> <info@avnet.co.uk>
>
>
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