reconditioning notebook keyboards?

I have a Vaio notebook on which the left shift key has suddenly
intermittently stopped working. I suppose the keyboard itself is relatively
easy to take it out

Does anyone know whether there is a procedure for repairing these or
cleaning the contact under the key which is obviously at fault? Are
notebook keyboards sealed units?

I ask because I have seen 'reconditioned' Vaio keyboards occasionally on
offer. I have tried deep-spraying Magneeto tape head cleaner all over the
affected area (with the key in place)to no great effect AND I have heard
reports from other Vaio users that their keyboards have failed (repeatedly)
in the same way, with first one key going and then a lot of its surrounding
keys as well.

"news.rcn.com" <news.rnc.com> wrote in message
news:IY2dnTWnRu8oQJjZRVn-uQ@rcn.net...
>I have a Vaio notebook on which the left shift key has suddenly
>intermittently stopped working. I suppose the keyboard itself is
>relatively easy to take it out
>
> Does anyone know whether there is a procedure for repairing these or
> cleaning the contact under the key which is obviously at fault? Are
> notebook keyboards sealed units?
>
> I ask because I have seen 'reconditioned' Vaio keyboards occasionally on
> offer. I have tried deep-spraying Magneeto tape head cleaner all over the
> affected area (with the key in place)to no great effect AND I have heard
> reports from other Vaio users that their keyboards have failed
> (repeatedly) in the same way, with first one key going and then a lot of
> its surrounding keys as well.
>

I can't speak about that particular model, but laptop keyboards, like most
these days, consist of two layers of clear plastic with printed conductive
tracks and contacts. Sometimes this may be one assembly (bonded together?)
and cannot be seperated. Keyboards are often held together by dozens of tiny
screws. Sometimes they are unfortunately held together by dozens of melted
over plastic pins for quick and easy assembly, making reassembly a
challenge.

It's not hard to open up keyboards, and once open the fault can easily be
found with a multimeter. I'd look for a broken trace next to the affected
key, and if you find one, repair it with rear car window demister repair
paint- available at car accessory shops. A thin coat is ideal, don't pile it
on, and allow it to dry thoroughly. Overnight at least to make sure it's
completely cured.

Failing that, clean the contacts with isopropyl alcohol or meths, allow to
dry thoroughly and reassemble. You may as well clean all the contacts when
you do this. In fact- I'd recommend you do this anyway, spraying head
cleaner on the keyboard was unwise and it may as well be cleaned properly
while it's dismantled. It's also possible the contact has worn out, you may
be able to repair this with the same conductive paint I mentioned, but don't
expect it to last.

Incidentally- spraying cleaner into a modern laptop keyboard will not clean
the contacts, it won't get anywhere near the contacts in fact. What it could
do is seep into the laptop's electronics and destroy it.

Dave