What problems do "Teflon actions" develop, and how can they be fixed?

[A440A at aol.com]

<<   Assuming that the "wretched" action you're describing is caused by 
high downweight and low upweight (the worst of both worlds!), it's either 
friction or geometry.   Regulation issues aside, with a '74 L, I'd first 
suspect 
friction. >>

I dunno,  in a '74 L  I would suspect the wrong combination of capstan 
placement and knuckle distance.  That will be a small teflon action with Pratt Read 
keys, I think.  Rarely do I find excessively tight pinning in the small teflon 
bushings, but I find a lot of short knuckle distances and misplaced rails.  
     The high downweight and low upweight sounds like they ran out of room to 
put lead in the keys......
Regards, 
 
Ed Foote RPT 
http://www.uk-piano.org/edfoote/index.html
www.uk-piano.org/edfoote/well_tempered_piano.html