Posts: 86
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Joined: Apr 2008
I think you just can't open it. The ball you see are not solder bumps, the keyboard is held together by "nails" which were just pushed-in with a press. They won't come out without destroying the whole thing.
Joel Setton
Posts: 1,162
Threads: 26
Joined: Aug 2005
Those aren't solder blobs, they're metal pins. Some HP9815 keyboards were assembled by screws (lots of them!), others with these pins.
I think you can get them out by warming them with a soldering iron and then using a pair of cutters to grip them and pull them out, Once they're all free, the PCB comes off, and the keys will fall out (I learnt that the hard way!).
If you can find some small self-tapping screws, I think I'd use those to reassemble it.
As to whether it's worth doing, I'd probably not bother. Too much risk in damaging something that still works. Now if a key didn't work at all, I'd take it apart.