Will Dinkins
5/9/2012
I recently managed the installation of a 5-V Crimp, 26 gauge "Galvalume" metal roofing system and my installer used a pencil to mark where he wanted to put the screws. These marks have now been in the elements for a month or so and will not come off. I feel that the marks are "baked" into the galvalume already. I know that you are not supposed to put lead or graphite on galvalume, but it was done and now I have to get it off or the owner will make me replace the panels in question. For the record, I have tried 409 cleaner with a soft rag as well as dawn liquid dish washing detergent with a soft rag with limited to no results. Your advice and recommendations are clearly needed and much appreciated. Thanks, Will in Charleston, SC
Todd Miller
Classic Products, Inc.
5/9/2012
Opening up for input
Will Dinkins
5/9/2012
By the way, the reason that this has become an issue is that there is a 3rd floor deck off of one of the bedrooms that just so happens to be eye level with the back of the roof and the pencil marks are clearly visible. We also have some red chalk lines in the valleys that are eye level off of the 3rd floor deck so if you have any suggestions how to clean those it would be much appreciated. Thanks so much for your help.
David Stermer
5/9/2012
Will, Thanks for the question. The reason that Galvalume is applied to steel is to protect the steel from corrosion. The effect of pencil marks on Galvalume is not to remain on the surface or stain the coating. The effect of pencil marks on Galvalume is to rapidly corrode the Galvalume and then the steel . It sounds like the pencil marks in your case have corroded the Galvalume coating. Cleaning the affected area will only serve to remove the compromised Galvalume, expose the steel and speed up the corrosion of the steel. I do not know of a Galvalume coating that can be field-applied. Any other coating will not tend to match. Panel replacement is the only way I know of to overcome the effect of pencil marks on Galvalume panels. Regards, David Stermer
Will Dinkins
5/9/2012
David, I appreciate your response and will replace the panels with pencil marks. I also have red chalk marks on one of my valley pieces, any thoughts on cleaning these panels to make them look new to the customer? Regards, Will
Will Dinkins
5/9/2012
Also David, in the future what do you propose my installers use to mark the panels for their nailing/screw pattern? Thanks in advance.
David Stermer
5/9/2012
Will, Some installers use a felt tip pen to mark the under side and then stack drill the panels all at once, eliminating the step of marking all the panels. I have used a sharpie to make a dot where I want to put a fastener and then the fastener covers the mark, with no need to come back and clean up. Regards, David Stermer
Guest User
9/7/2012
in our factory we only use felt tip pens no troubles
David Mongeon
10/3/2012
I believe I read someplace that blue chalk will come off but red will tend to stay (I know this doesn't help you get the red off, sorry).

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