Check Steel Type

Q. I read with interest your reply to E. O. concerning his adhesion problem to the steel he’s purchasing from a new supplier.

Although I completely agree with your answer regarding cleaning of the surface, you only touch on the type of steel that he uses. Cold-rolled sheet steel goes through a few processes, and this carbon steel can also be alloyed in varying amounts, depending upon end use. I would have advised him to contact his sheet metal supplier first since the only change was the steel source.

Prior to being in paint technical sales for 30 years, I manufactured electrical items, one of which is the clock plate on which you plug in and hang a clock. This was the size of a conventional wall plate, but had a deep-drawn center where you plugged in the clock. We changed sources for the deep-drawn steel and we started to get sporadic cracking in the side of the deep drawn section. To make a long story short, after trying different drawing oils, we went back to the original source for the steel.

In an analogy, how often were you told that a certain resin was the same as what you were using and completely compatible with your pigments and additives? Only in the field did you find out that there were problems when you switched suppliers.
Before I go through the cleaning process, I would attempt to solve my problem by checking the steel sheet and testing different types of sheet from the supplier. Remember, this was the only variable in the situation. S. B.

 

A. S. B. is referring to E. O.’s question “Choosing a Cleaner” in the June 2007 Painting Clinic. Thank you for writing, S. B.