Osborne 1 keyboard repair - success!

[Tom Hunter]

Hi Patrik,

As to the superglue - it was the only option because the prongs are just
melted flat. To get the key mechanism out or off I had to scrape all the
melted plastic off. I then subsequently re-attach the key mechanism to the
aluminium backing board by applying a tiny drop of superglue between what
was left of each prong and the associated hole in the aluminium backing
plate. The key mechanisms can be pushed out again with moderate effort if
it is ever necessary again.

Best regards
Tom Hunter



On Sat, Nov 21, 2020 at 1:36 AM Patrik Schindler via cctalk <
cctalk at classiccmp.org> wrote:

> Hello Tom,
>
> Am 20.11.2020 um 15:11 schrieb Tom Hunter via cctalk <
> cctalk at classiccmp.org>:
>
> > I have managed to completely disassemble the bad Osborne 1 keyboard
>
> Congrats on that!
>
> > The silver tracks remained undamaged as confirmed with a multimeter.
>
> Very wise to check this while all is disassembled.
>
> > I then carefully reassembled the 3 layers, inserted and super-glued the
> keyboard mechanisms in batches, testing after each batch.
>
> When using super-glue, will this possibly negatively affect the ability to
> disassemble the keyboard again? As far as I’m aware, the prongs are most
> often just pressed flat with a hot iron to melt and thus held in place.
>
> > I did not use any glue to reattach the 3 membrane layers so they are
> held together only by the keyboard mechanisms with their prongs protruding
> through the layers into the aluminium backing plate to which the prongs are
> super-glued.
>
> Very good idea!
>
> > The conclusion is that membrane keyboards can be fixed if your life
> depends on it. It is absolutely uneconomic though. I worked about 30 - 40
> hours on the keyboard alone. Working Osborne 1s sell for between US$100 and
> US$300 on Ebay.
>
> Well, with some routine you can become an expert and do that repair in 1-2
> hours. All membrane keyboards are very much alike. While I’m truly appalled
> to do this for a living, I’m not frightened about doing this anymore. ;-)
>
> :wq! PoC
>
>