Renovating gang switches

[N_Cook]

Confronted with a huge Rotel amp from mid 1970s.
Function switch, interlinked S/R ganged switch, 5 gang, each of 4 pole 2 way
with pins extending above and below and a pcb above and below . One failed
switch contact. I'm surprised I've never had to break into one before,
serious miultiway radio waveband switches , yes, but they are not ganged.
This make of logo TMS in an elipse, hopefully applicable to other makes of
ganged switches.
How to get inside without desoldering all that lot.
U channel steel between the 5 gangs has 4 nibs , bent over, to trap each
gang , bend back those 4 and the next 4 along the gang strip to give some
lee-way. Small blade between that channel and the sw body to lever and give
enough gap to release the S/R interlink that runs inside the U channel , and
in this one release a nylon limit widget , from under the spring and then
the core of the gang simply slides out. In this case aged/compacted grease
had wedged the phosphor-bronze contact away from ever making contact

 

[Smarty]

Confronted with a huge Rotel amp from mid 1970s.
Function switch, interlinked S/R ganged switch, 5 gang, each of 4 pole 2 way
with pins extending above and below and a pcb above and below . One failed
switch contact. I'm surprised I've never had to break into one before,
serious miultiway radio waveband switches , yes, but they are not ganged.
This make of logo TMS in an elipse, hopefully applicable to other makes of
ganged switches.
How to get inside without desoldering all that lot.
U channel steel between the 5 gangs has 4 nibs , bent over, to trap each
gang , bend back those 4 and the next 4 along the gang strip to give some
lee-way. Small blade between that channel and the sw body to lever and give
enough gap to release the S/R interlink that runs inside the U channel , and
in this one release a nylon limit widget , from under the spring and then
the core of the gang simply slides out.

In this case aged/compacted grease
had wedged the phosphor-bronze contact away from ever making contact

Spray with DeOxyIt !!

 

[N_Cook]

I tried opening a more recent ALPS multi-gang switch, laying around, with
pins emerging top
and bottom. Much the same routine to extract the core , no ball bearings or
anything other than the contacts are likely to drop out. Easier to
reassemble than those long radio waveband switches, laty the innermost pair
of contacts in their wells, push in, then add the next pair and push in.