In a previous thread we saw HP-15C LE fixed, but I found that fix too complicated. So I decided to sacrifice my calculator and do it myself and I'm no good with such repairs.
I used only my Swiss army knife, a small screwdriver and two component epoxy glue.
Heat stakes are very easy to cut off flashing with the PCB - the plastic the are made of is somewhat soft, jelly like.
The offending key had a little white plastic ball - about 0.1mm diameter - stuck at the dead center of the metal dome - and I had to apply some force to remove it.
I can't tell more about the material of the "ball", it got lost somewhere in the cotton bud I used to take it off...
Reassembling was easy - PCB stood quite firmly even without heat stakes heads being glued - I tested it like that for a day. Eventually I put a little drop of the glue on top of the heat stakes and that way sealed them. I believe this is enough to keep it firmly in place.
A tricky bit is there are 3 little spiral springs abt 20mm long that are very easy to loose when opening the calculator.
It's working perfectly now - will see for how long ;)
Cheers,
Edited: 24 Nov 2011, 8:14 p.m. after one or more responses were posted