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Old 12-06-2018, 03:07 PM
NOT A TA NOT A TA is offline
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Join Date: May 2005
Posts: 178
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I'm back with more positive results from long term torture testing unpainted as well as painted samples.

From my last post to the end of Oct. (6 months) i put the sample board through cold temp testing. I'd put the sample board in the refrigerator, next time I opened the fridge I'd put it in the freezer. Next time I opened the freezer it'd go in fridge, then from fridge to floor in kitchen (mid 70's F). Then next fridge opening it'd go back in. So the routine was floor, fridge, freezer, fridge, then back to floor and repeated constantly. I did this as it kinda seemed like the best way to simulate going from cold outside to heated garage or vice versa. Then I tried the fold//twist testing at outside an temp of about 80 F. No cracking, peeling, or other adhesion issues.

I then figured I'd increase the rate of temp extremes difference to see if that would cause any issues. So I'd put the board outside in direct sun then directly into freezer. From freezer the next day into mid day FL full sun with temps already in high 80's let it get hot then back into the freezer. After a month the pieces with just CC, ones with BC/CC, and ones with acrylic enamel with flex agent all passed with flying colors. There were no samples left of other brands to do any of the cold testing with because they had all failed previously.

Still no difference in adhesion noted whether adhesion promoter was used or not and also between brands of adhesion promoter.

Pics from today.






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John Paige
Lab-14.com