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Kynar vs. SMP
I know that Kynar is a better finish that SMP. However, the color (a medium green) and metal profile I want to use is only available in SMP.

I've looked at the performance specs for both types and found that Chalk value is 8 for Kynar and 6 for SMP; Fade is 5 and 8, respectively.

Its extremely difficult to ascertain what the paint performance, based on these values and on the color used. The reason is that chalking/fading on a white (or light paint color) would be less critical than on a dark paint color.

My question to you is: Is there a source on the web where these values are explained in visual terms for each kind of paint For example, I would like to find the following statement:

"For a chalk value of "6", one can expect to find chalking becoming visible after x amount of years on light colors"
These are unfortunately hard things to really fasten down.

First of all, though, in the numbers you're comparing -- make sure those ratings for fade and chalk are for the same time period. You may find that they are not. In fact, I think you will find that to be the case.

Fade and chalk will occur more quickly in harsher climates -- areas with more sun or high elevations obviously.

Historically, very rich or "saturated" colors will be the hardest to hold color ... this would be very deep reds, blues, purples, greens, etc.

"Muddier" and "softer" colors which have more pigments blended into them tend to hold color best.

Fade resistance comes largely form the type of pigment used. Ceramic pigments seem to hold color best. All Kynars / Hylars use ceramic pigments. Some SMPs do as well. They are the most costly pigments.

Chalk is avoided by the resin quality, which is a chief benefit of Kynars / Hylars -- the quality of the resin.

Fade is not really something you can approximate or "show" as colors may fade in different directions, depending upon the exact pigmentation. For example, a brown could fade toward the red or the yellow or just get lighter, all depending upon the exact pigmentation and which pigment "goes" first.
I hope this helps some. I know it is not an easy subject.
Robert, there are a number of metal panel manufacturers where you can get almost any green or color in a Kynar finish. The biggest problem with SMP is that the color will fade and flake within a 10 to 12 year time frame. That is not the case with Kynar coated products.
Thanks Stan
What Mfgs have lots of green?
ATAS, Petersen, Fabral, Drexel, Custom-Bilt -- all come to mind.


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