John Hall wrote:
Just got the Dec/Jan Copy . In the article titled"Shop compressed air for in
house tire service" The author describes in detail a coil of copper tube he
installed in his air line, but doesn't tell us why. Am I missing something?
Is it obvious why? All I can see is it adds volume to the system and might
be a good way to camoflage a still from the revenuers.

Anybody have any ideas?

This is commonly done to act as a heat exchanger. The hot air leaving the
compressor is cooled somewhat by being passed through the copper tube
where some of the heat is radiated to the air. Presumably this cools the
air enough so that the water vapor contained in it turns to little drops
which can be collected by a filter. I always thought of putting a copper
coil in a bucket of water, into which one or more bags of ice could be
dumped for peak need if necessary. Perhaps a coil in ambient air would
be enough.

I thought his construction (the coil mounted up under a workbench) was
well done, and the article was well done and interesting too.

GWE