To clean - or not to clean ... ?

[isanchez]

Hi,

Congrats for the finding! It is really a remarkable calculator.

I collect these calculators and I have a large amount of them.
In my opinion: Do not open it, if not necessary, which is like saying: if it works fine, do not open it, moreover if it is necessary to break or put in (serious) risk aestethical aspects, which is the case.

I would distinguish between external cleaning and external restoring. I like to keep clean the calculators (some people talk about keeping the "patina", I talk about removing the dirtiness) and only in some cases, restoring. I.e. there is a big debate about restoring the silver lines in HP35 or not...this is a personal decision. ;-D

Enjoy your HP35!

Kind regards

Ignacio