[R-390] White lines on knobs and more

[Don Reaves]

One tidbit I learned along the way about painting or powder coating
aluminum is to get it clean before applying primer or alodine or
whatever.  By clean I mean no grease, oil, dirt, or fingerprints.  The
quick method I use is to lightly scrub the piece with a light dusting
of plain kitchen cleaner Ajax and a plastic scrubbing pad using
distilled water. I wear latex gloves to avoid contaminating the
workpiece.  My tap water has a high mineral content, and distilled
water is inexpensive so I use that.  Also use distilled water to rinse
off the Ajax.  The test to see if you have the item clean is water
should gravity flow off the piece in sheets, and not bead up.  If it
beads up, or droplets form, it's not yet clean.  Dry the piece once
clean and its ready for the next surface treatment.

Don W5OR