[pianotech] Stuck solenoid

[Dean May]

I've also found another cause: the rubber tip binding against the bottom of
the key. This problem crops up when the bottom of the key is at an angle, or
the plunger is not 90 degrees to the bottom of key. As the plunger comes up,
the angle becomes more acute, the rubber tip locks in place and won't slide
back to rest position. I've applied thin CA glue to bottom of key, sand with
400 grit paper to make bottom of key glossy smooth, then apply judicious
amount of lube. 

 

Dean

Dean W May                (812) 235-5272 voice and text 

PianoRebuilders.com    (888) DEAN-MAY        

Terre Haute IN 47802

  _____  

From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Larry Fisher RPT
Sent: Wednesday, July 25, 2012 9:54 AM
To: pianotech at ptg.org
Subject: [pianotech] Stuck solenoid

 

I'm assuming this is a PianoDisc.  The solenoid sticks for three reasons
that I've found.  Debris gets in the chamber and binds betwixt the plunger
and the walls of the chamber.  Lifting, spinning and then dropping the
plunger in one smooth motion numerous times sometimes dislodges the
offending particle.  Then there's the binding stem.  Spin the plunger and
see if the tip wanders.  If so, straighten it.  Be gentle with this.  After
straightening, if it still binds, locate the offending point of contact and
relocate the neighboring solenoid.  After ruling out the first two reasons,
you're left with a warped chamber or barrel.  The solenoid was either wound
too tight or it got hot and warped the barrel to the point that the plunger
is now rubbing on the inside walls of the barrel or chamber.  Replacement is
the only fix.  Any PianoDisc installer should have one laying around for you
to purchase.  If they are the type that wrap around the rail using a quarter
inch screw, you don't need to remove all the solenoids to get the old one
off.  Just remove the screw all the way and it should come off easily .....
solo.  There was a short production run that used torx heads on the current
styled solenoids.  Current styled solenoids are easily replaced one at a
time.  You'll need a quarter inch nut driver.

 

Allow at least an hour labor  ............  pedal mech removal, rail cover
removal, rail removal, solenoid R and R.

 

Lar

 

 


What's the best way to lube a stuck solenoid?

Rick Ucci
Uccipiano.com

No virus found in this message.
Checked by AVG - www.avg.com
Version: 2012.0.2197 / Virus Database: 2437/5154 - Release Date: 07/25/12

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://www.moypiano.com/ptg/pianotech.php/attachments/20120725/9f68c550/attachment.htm>