Front panel material

[terry michaels]

Hello list members:

I am planning to make some front panels similar in appearance to those used
in the Moog modular systems.  Basically, those panels are 0.063 inch
aluminum sheet, with the sides bent back to create a shallow U shape to
increase rigidity.  The panels are black anodized, and then lettering is
added by etching, although white silk screening is a possible alternative. 
The question I have is, what alloy of aluminum was originally used, or
should used be used today?  6061-T6 is by far the must available alloy, but
it doesn't appear to be what was used in Moog modules, a few of which I
have here.  6061 is fairly soft, when you drill a hole in it, the back side
of the hole mushes out and always has a burr, and the drill bit tends to
clog.  I have a few scrap pieces of another, harder alloy, I'm guessing it
might be 5005 or 5052 or something similar.  This alloy gives you a clean
hole when drilled, the drill bit cuts small chips which don't clog the bit
as easily.  Also, when you bend it, the outside of the bend develops tiny
longitudinal fractures, identical in appearance to the bends on the Moog
modules.  The same material seems to have been used in my Minimoog also. 
Does anyone have any thoughts on this?

Terry Michaels