Fatar TP60 contact failure - cleaner or new bubble contacts?

After ten years of pummelling, a few keys on my Fatar TP60s (the ones with metal key shafts, double bubble contacts, "tracker touch" and a spring at the end) are going from being intermittent to no longer working. I've tried the gentle massage of keys approach but fear I'm going to have to dismantle the console for a more radical approach. I've gathered there are three techniques:

1. remove offending key, blow off dust around the bubble contacts, maybe massage the bubbles, and hope for the best - I've done that already with a few notes but not sure how long I can keep doing it for;

2. remove a dozen keys, pull up strip of contact bubbles, apply some sort of contact cleaner (or is it some kind of electrical contact paint you apply)/ What's the best stuff to use and how robust is that as a repair?

3. am I better off just chucking the dozen contacts and fitting new bubble strips? If so where can I get them besides Classic Midi works who stock them as a spare and explain how to do it with photos on their website? In particular are there any UK suppliers? Getting hold of Fatar spare parts seems to be somewhat haphazard.

Methods 2 and 3 involve removing 12 notes to access the strips which would have its own risks as there is quite a knack to getting them out and back again, so I'd rather not do that if possible. How have others approached missing notes on Fatar keyboards?

https://www.ebay.com/itm/MUSIC-KEYBOARD-PIANO-SYNTH-REPAIR-Fix-Conductive-Keypad-Switches-Key-Contacts/181662188354

Rgds,
Ed

After ten years of pummelling, a few keys on my Fatar TP60s (the ones with metal key shafts, double bubble contacts, "tracker touch" and a spring at the end) are going from being intermittent to no longer working. I've tried the gentle massage of keys approach but fear I'm going to have to dismantle the console for a more radical approach.

I figured the Plastic Bubbles had just worn out from time and use. So I ordered enough strips for a full keyboard (four strips of twelve and one strip of thirteen) and replaced them all... an octave at a time. Removing an octave's worth of keys (plus one or two extra on each side) gives adequate room to work, and still makes it possible to keep all the keys in order, so each one goes back afterwards to where they came from.

Use some little tool (like a straightened paper clip) to detach and re-attach the springs on the back of the keyboard.

The trickiest part is fastening the new strips in place, by poking into little holes in the strip (with a paper clip) to force the little pegs on the strip into the little holes on the printed circuit board... but never pushing too hard, or the paper clip perforates right through the bubble-strip and that particular point of contact might prove very tricky to get properly seated thereafter.

Be sure not to install the strip backward (rotated 180 degrees).

When properly installed, the strip should lie perfectly smooth and flat on the Circuit Board.

I didn't try cleaning any contacts, because I didn't suppose it would be necessary or helpful. In any case, the repairs worked out OK. Of my three manuals, only the second one ("Great") has needed repair, presumably because it gets lots more use than the others. I've done this procedure twice now, at intervals of several years each. The second time, I had to re-do one octave because a piece of hair got stuck under the contacts, so one key would not play until this was attended to.

Good luck!

Thanks for the suggestions - I've managed to source some contact cleaner.

However there's a complication. Firstly I noticed earlier today a third note that isn't playing. The three notes on the one keyboard that haven't been playing are each eight semitones away from the other, which makes me wonder (and worry) whether the problem is not actually deteriorating bubble contact but something to do with the matrix circuitry (my MIDI cards are Doeffer MKEs, each of which is connected to its TP60 manual by two ribbon cables). The three missing notes all suddenly started working again this evening whilst I was practising, which I wouldn't have expected if one or two had been silent due to a poor connection at the level of individual notes.

If there's a dodgy contact somewhere else that's causing notes in the same matrix pattern (is that the way to describe it) to be silent I have no idea how to investigate that, other than to swap the keyboard over and see if the same keys on the same manual are intermittent if the manual is placed elsewhere, of if a different keyboard in that position starts to lose notes. Equally I'm a bit reluctant to disassemble the manual known to have had missing notes to clean the contacts if the problem is somewhere other than the rubber contacts.

Armed with that additional information, can anyone offer further advice please?

Armed with that additional information, can anyone offer further advice please?

I would unplug the Ribbon Cable(s), one at a time, for the affected keyboard (at each end of the cable) and then plug it back in to see whether that little bit of friction might improve the connection.

Simply plugging in the connectors "properly" might fix it. Micromatch connectors are ridiculously easy to dislodge and if that has happened you would get the symptoms that you describe.
Good luck!
Graham