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Standard Specs for Aluminum Curtainwall panels

I work for a general contractor on a job with Alucobond composite aluminum panels in the curtainwall. The paint specified is a metallic coil coat.

There exists discoloration among the panels depending on the "direction" of the panels. The arrows should all be horizontal, pointing in the same direction. (Most of the don't even have the directional arrow identifier).

The question is do composite/aluminum panels have a industry standard variance - tolerance?

The specs say: 1) "Comply with NAAMM's "Metal Finishes Manual" for recommendations relative to applying and designating finishes. 2) Finish designations prefixed by AA conform to the system established by the Aluminum Association for designating aluminum finishes."

I can't get to a NAAMM website and what are the AA designations?

Gorgea Davidson
DPR Construction, Inc. - Redwood City, California USA
2000

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www.aluminum.org - The Aluminum Association (source for the AA designations you asked about)

Another good source for finish specs regarding the AA would be www.anodizing.org. They are the Aluminum Anodizers Council and they tend to have information regarding the AA specs along with a small info blurb and a cross reference of sorts.

Matthew Stiltner
J & J Plating Company - Toledo, Ohio
2000

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I am part of a company that deals with one of Alucobond's competitor. So, I will not comment on the product but I can give you some basic information

1) All composite panels are coil coated. This means that especially for metallic colours the direction of the panel reflects the shade of the colour due to the orientation of the metallic pigments. In short if you install one panel vertical and the other in horizontal direction, even if they are from the same batch of paint you will find a difference in shade.

2)To avoid the above mentioned installation problem the coated surface of the composite panels is always protected with a protective film that has directional arrows in it. this film is applied while the panel is made, thereby avoiding mistakes on the part of the manufacturer.

3) fabricators sometimes remove the protective film and end up installing in different directions.Mistakes are also found to be made during design and ordering stage. Some people try to cut corners to avoid wastage and neglect this most important aspect and finally find that they have done a poor quality job.

4) regarding the standards on painting, you can refer to any standard PVDF coil coater who will be able to supply you with copies of all norms

hope this answers your question.

A John
reynolds - Sharjah,UAE
2000