[R-390] Front Panel Restoration ER Don Reaves

[Don Reaves]

No need for any apologies, Glenn.  I was happy to make my small
contribution to your article because you introduced me to the effectiveness
of soda blasting.  I am using soda blasting with good to excellent results
for all sorts of restoration projects, including removing peeling latex
paint from home exteriors.  But I didn't spend big bucks for professional
equipment.  I used the soda blaster kit available from the Chinese Junk
Shoppe, AKA Harbor Freight, and my standard shop air compressor, a
Devilbliss 5CFM at 90 PSI, 20 gal. tank.  It works but I do have to go slow
to allow the compressor to keep up.   I did add an extra air line filter at
the blaster tank air input and only use the setup on lower humidity days
outdoors.  I'm not doing R-390 panels - mostly I'm stripping and repainting
WWII era black wrinkle painted gear like ARC-2 and BC-348 cabinets, and
some custom rack panels that match ART-13 panels.

The purpose of the zinc chromate is bonding to clean bare aluminum for
paint adhesion.   Just painting bare aluminum panels without proper primer
means you will be repainting again when it starts flaking off.     Steve
mentioned Bulldog adhesion promoter.  I'll have to try that.  There are
other primers for aluminum, such as Marhyde self-etching primer and
aluminum "brighteners" like Duragloss 851, which contain an acid that
lightly etches bare aluminum that promotes paint adhesion.  Lately, I'm
getting interested in powder coating my projects since I found that black
wrinkle media is available for power coating.  As is machine gray.   Hmm.

Painting is an art, not a science.  I'm on my third try now trying to get a
good match repainting the matching power supply (Navy CT-20086)  for an RBM
receiver.   I get a good paint color/texture match but botch the job with a
paint run, or get a good paint covering but the color/texture is off.
Hats off to guys like Glenn that get consistent professional results!