CRS is an abbreviation of the manufacturing process, it stands for
Cold Rolled Steel. In this process the steel is pressed between two rollers to achieve a uniform thickness. When metal is worked below its 're-crystallisation' temperature it is said to be 'cold worked'. However, the metal may be purposely heated or still quite hot from another forming process such as hot rolling or forging.
Lysaght were suppliers of steel to VW Australia, in the '60's when full local production was happening, it probably arrived by train at the Clayton factory in "coils" like this:
They would have been fed through Clayton's huge presses to be stamped into various body panels. I can't see Lysaght going to the trouble of re- rolling the coil (once it's been formed) just so they can put a stamp on every few feet. So, I would imagine the stamp was applied just to the outermost roll of the coil (for product identification) once it had cooled.
So, your roof skin seems to be lucky enough to have been pressed from the first few yards of a Lysaght coil as it was fed into the panel press at Clayton. The stamp was protected by the initial phosphate coating used in the factory on bare metal, there would have been no need to sand the stamp off as there were four coats of paint to come, so the stamp had no chance of showing through. Being only at the beginning of the coil explains why people don't find these stamps too often.
From: Knowing Australian Volkswagens, by Dave Long & Phil Matthews.
The factory did four coats of paint - first a phosphate coating over the bare metal to improve adhesion, then came the black dip in a tank to protect every part of the body. This was followed by grey undercoat, cream filler and finally a baked enamel topcoat, provided by oil fired radiant heat ovens.
Regards,
Matt.
