HP-67 a nearly hopeless case

[Geoff Quickfall]

Dr Mabuse:

NEVER use Armorall on the keyboad bezels. It would be okay on the exterior of the shell but NO where near the silkscreened keyboard bezels.

As the calc ages, it is exposed to chemicals (lab environment) and UV. This decomposes the clear lacquer used to protect the silk screened script.

Even a fine make up brush with a dilute solution of dish detergent (liquid) can remove the script. Always pat dry the keyboard bezels, never wipe dry.

Geoff

P.s. Do your have a first name?