Mention was made of ozone generated by electrical sparks causing
deterioration of rubber parts and such.  This caused me to remember
a situation I discovered some years ago.

I had an Ampex 4-channel audio tape recorder which used a neoprene
"O"-ring drive belt to spin the capstan which had a massive flywheel
running on instrument ball bearings.  This made a for very constant
speed with no detectable wow or flutter.  I was living in South Western
Arizona (Yuma) at the time and I usually got about 5 years out of a
drive belt before it began to fail.  I moved to Pomona, CA, with the
smog and such.  I could get about 18 months out of the same belt.
Fortunately I discovered a silicone rubber replacement belt from GC
Electronics which was good for four years or better.

My point is that smog, and in particular sulfur dioxide, are hard on
many sealing and gasket type materials.  You who have not discovered
this might keep that in mind.

I just finished a complete rebuild on my Franklin Ampico A upright.
Came out very well.  Thanks all of you for the invaluable information
and tips.

Jim Cook
Riverside, CA