K6 frame material
 

Been a bit clumbsy with the tools and have a made a light surface scratch on the frame of my 3 month old K6.

You can see the metal underneath.

Am I correct in thinking that it's not made of the usual Suzuki cheese but nice expensive aluminium which will form a protective layer on contact with air meaning that the damage is purely aesthetic?

Well... Pretty much any aluminium will, the surface oxidation is quite an effective sealant provided you don't clean it off. But I'd touch it up, myself, just a dab of touch-up pen would both seal it and make it look a bit nicer, if you do it well. Or Humbrol model paint :) I reckon it works better for simple colours than celly touch-ups do.

Ta :)