The photos below are examples of what can happen to cold-formed panels after only a few years of exposure to the elements. And not just roof panels. The photos below are both sidewall panels.
The panels above were made on a cold winter day. And when the flat steel sheets went through the forming process, rather than bending with the steel, the paint cracked.
It was only a matter of time before rust started showing in the tiny cracks.
But it is important to note that cracking doesn’t just happen on cold winter days. According to United States Steel Corporation, the steel needs to reach 120°F – 170°F or else…crack.
If steel panels were painted after they were rolled out into their unique profile, cold-forming wouldn’t be a problem.
But that’s not how it works.
Instead, the 5-ton coils come pre-painted from the factory.
So what is the alternative to cold-forming?
It’s basically an oven. An oven that gets really hot.
Like 1,000°F hot!
In the second it takes for the steel to pass through the heat box, it goes from room temperature to over 125°F!
The oven temporarily softens the paint, which allows it to flex and bend with the steel as it goes through the roll former.
Still not convinced? Check out the comparison in the graphic below.
Should all painted steel be heat-formed?
SMP coatings like Valspar’s Weather XL paint system are less flexible than PVDF coatings like Kynar or Valspar’s Fluropon paint systems.
In addition to this, the bends of the ABSeam panel (pictured above) are not as tight as the bends of the ABM Panel, which puts less stress on the paint.
Those are two of the reasons why the ABM Panel is heat-formed steel, while the ABSeam panel is not.
If you don’t want any problems down the road, make sure your SMP-coated metal is heat-formed.
A. B. Martin is a Manufacturer and Supplier of Quality Building Supplies. Contact us to speak to one of our knowledgeable sales representatives.
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