[AT] Was: Lapping Air Compressor Valves

[Sheppard, Charles E]

Well, I followed Pete's suggestions on lapping the disc-type valves in the old Westinghouse air compressor.  I lapped on a piece of 1/4" plate glass I cemented with shellac to a thick piece of MDF.  The smaller valves weren't too bad but the larger valves on the LP cylinder took some time.  The heat was too much for me last week so I finished it up today.  After a little work on the oil pressure unloader (bypasses HP to LP) I put it all back together.  I rolled it over and , just like you said Pete, it has a nice groan to it.  And it runs like a champ...I'm very pleased.  Thanks for the help, Pete.
 
Now I need to work on air distribution and I definitely do not want steel pipe.  Copper is pretty pricey so I'm thinking plastic.  I know this was a discussion topic a few years ago, or so, but what is the veredict on the flexible polyethelene, 160lb.stuff?  Maybe I would use copper on the drops to the connection ports.  I would like to run air to several places and, counting all the zigs and zags, it will be a little over 100'.  Any thoughts?