restoring an HP-01 keyboard


dear all, i'm trying to get to near mint conditions my HP-01, which has some discoloration on the rigt side of the keyboard. It doesn't affect the keys or the functioning, but, I'd like to have it fixed. I've tried (with poor results) with a black CD marker softpen, does anyone of you has ever tried anything better than this ? Thx for help, Alberto


Ciao Alberto,

a couple of days ago I read this article. The author also describes the restoration of keys and keyboard. IMHO the procedure is very delicate and one can do a lot of damage. Another interesting thing about this article is, that the author has done a reproduction of the red watch crystal and is probably sharing (selling?) it.

I'll be glad if you would post a story of success with pics, when you're done. I'm still looking for an affordable one (which should be in a condition that still allows for refurbishing).

Good luck.




Hello Alberto,

A quick response, unfortunately the CD 'sharpie' marker are temporary at best.

I am hoping for an air brush system for Christmas (or I will just buy one). I saw a posting about building up the finish with an air brush. See the link Ranier posted as he beat me to this!

Again this should last longer then the airbrush but it has not got the durability of a paint that was baked on as the original is.

Sorry, no help here but if you have an air brush that might work better.

I have done eleven restorations to date for people on the HP-01 and even made my own crystals from armoured plexi glass. These do not have the Hewlett Packard label/name on them. I prefer the armored plexiglass as it can be polished at any time to remove scratches. The mineral glass can be polished with water and diamond paste only when removed from the watch, even then it is a long involved process.

If your crystal does not have any major chips from the corner (pictures?) then after removing the movement the crystal can be removed and flipped over.

I will email you later and DO NOT start a dis-assembly UNLESS you know what you are doing!!!! Removing the battery holder can destroy the PCB if allowed to rotate.

Cheers, Geoff

Edited: 18 Oct 2009, 12:58 p.m.


ciao a tutti !(hi everybody),
and again thank you very much for you help.

Again, I'm not disassembling the watch, I admit I'd love it, but I
have waited to much for it. I'm attaching an image, please considered I have already polished the bracelet (again thanks for help in shortening it) and changed batteries. As you will see it's in fair conditions, but, I'd like to fix the right side of the keyboard painting (that's the most annoying thing to me)

I have tried with the CD marker, but I don't like very much the result, if you look closely at the watch you can see an additional layer of painting. Any, and I mean any, suggestion will be appreciated. Take care, alberto


by the way, S/N for this is 1712A32861 ...


Nice watch and the keyboard doesn't look bad!

The airbrush technique is the only semi permanent way of repair that I have seen.

Your crystal is an excellent canditate for flipping up side down but of course the hewlett Packard would be missing.

It is amazing how much a good crystal changes the appearance of a watch.

Did you get the email I sent?

Cheers, Geoff


Dear Geoff,

yes indeed, you should have received mine by now,
I'll think about the airbrush, although I don't have one,
but I can always get one from some friends. Would you really
flip the crystal ?

Take care Alberto



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