Keyboard label wear

[Dixit]

Indeed. And if you succeed in removing the dirt from the etch, you will have removed the letter itself as well.

I am intrigued in how you will cover (and with what) your Gemini keyboard. If that material also ends up in the micropores, then it might actually worsen the issue.

How did you get a Gemini under a microsope ? Where did the light come from ?

[gidds]

I just got reply from Planet:

...The keys on the Gemini are lasered, so they will never completely wear off. While it might discolour, they will eventually stop fading.
...

Hmmm…  It's pretty obvious, even without a microscope, that the lettering is in relief — it sticks up from the keys, rather than being sunken into them.  So while a laser may be involved somehow, this doesn't seem like ‘etching’ as a layperson would understand it.

The microscope pictures above are very interesting, thanks!  And the pixelation of the lettering does suggest a process more like silk-screen printing.  (I can just about see it with a magnifying glass — both on my Gemini and a 5mx.  Which surprises me, as I thought there was nothing about the 5mx I didn't already know  )

But yes, the bottom line seems to be that they seem to be made pretty much the same as Psion keys.  And my two decades of experience with those indicates that while the lettering does unfortunately discolour, it doesn't get removed, even after many years of use; and in most cases it never progresses far enough to endanger the legibility.

[Ifanafi]

Close inspection of my Gem's keyboard also shows wear (grime?) on the most-used keys, particularly the Shift key.

I wonder if, after cleaning with something like eyeglass or made-for LCD screen cleaners, the keys might be sealed (and protected) with something like clear, hard, acrylic or enamel nail polish (as CNET suggests and states lasts one year)?

BTW, cleaning Gem keys with water and mild detergent or something stronger like Isopropyl alcohol necessitates Gemini's keyboard lettering meets keyboard industry standards.

Ifanafi

I've had my UK Gemini for 3 weeks and now that you mention it it does look like it is starting to wear, I had put it down to the keys getting a little grubby so I looked a little closer and to me it does look like dirt rather than the white print wearing off,
see attached image

[Eldkatten]

Hello,

(...)
It appears that there might be just dirt in the microscopic holes afte laser etching, not easy to clean.  
(...)

I would now like to second that. I detached the ESC-Keycap from my Psion 5 mx and first cleaned it with detergent, dried it and then used isopropanol. Looks much better now, though not as good as new. Maybe a round in the dishwasher (of the separated key caps, of course, not the entire psion) might do the trick. In any case this does look as if not the "printing" is worn of, but it is just darkend by absorbing oil from the skin of the fingers. What also speaks against abrasion is that there are no gaps in the printing, just darker parts, or the whole printing has gone dark.

I am much calmer now concerning the Gemini keyboard.

(...)
Hmmm…  It's pretty obvious, even without a microscope, that the lettering is in relief — it sticks up from the keys, rather than being sunken into them.  So while a laser may be involved somehow, this doesn't seem like ‘etching’ as a layperson would understand it.
(...)

Well, being a layperson myself, I don't actually know how it is done, but this is definately not printing. In my pictures you can see the "paths" inside the symbols, where the laserbeam or maybe a plasma beam has worked and inserted the white color. It actually looks like a tiny micro 3D printing.

Nevertheless I would like to see a clear close-up picture of MikeC's ESC key, since he says

(...) The Esc/on/off key label is almost completely gone.(...)

"almost completely gone" should mean the white (or whitish-gray) print is away leaving only the dark gray surface of the key cap. Is that the case?

Kind regards

[Dixit]

Yes, MikeC's response is definitely key here. Ha... pun intended.

Anyway, on the subject of (laser) etching.

I am a slide rule collector and those fine precision instruments were also generally being made by etch techniques, though not necessarily laser etching.
It can clearly be seen, that the scales of some slide rules are also on the slide rule, instead of being in it.
Thus, despite the name 'etching' it is common to see the letter (or number) on the device.
This is particularly the case for the red scales, whereas the black scales usually show grooves indeed.
You can see entire red digits and hair lines on the ruler. No microscope needed.

Now for the bad news...

Though this was already considered a standard technique for all manufacturers, you could clearly distinguish the bad manufacturers from the good ones.
My German Aristo's are all as new... except for the cheap U-models.
My English Unique's are entirely worn (though some have neer been used). Indeed, a Unique quality level.

It all depends - again - on quality control.

Now, of course those slide rules are at least 40 years old. Not sure if that is really needed for the Gemini...

[Eldkatten]

Off-Topic: ShowHide

(...) I am a slide rule collector (...)

"slide rule collector"? Frigging Awsome!  

[gidds]

this does look as if not the "printing" is worn of, but it is just darkend by absorbing oil from the skin of the fingers.

Mmm, that could well explain it.

It actually looks like a tiny micro 3D printing.

Yes, it does.  Of course, actual 3D printing wasn't available 20 years ago when the Psion 5 was made, which is why silk-screen printing (where the ink/whatever is forced through a fine silk mesh) seemed a possibility.  Ink-jet-style printing (which is what 3D printing was based on) could also result in something like that.

However, videos such as these definitely show lettering being created (in impressive style!) by laser.  And that's apparently the standard way for keyboards, especially when they're not in long production runs.  (Other methods are ‘double-shot’ moulding where the lettering is in a contrasting colour of plastic, and dye-sublimation printing.)

I haven't seen a good explanation of laser engraving, but I suspect that the laser heats the plastic, causing it to expand and discolour (perhaps in the same way that soft plastics can change colour when bent/stretched).  This would explain everything: why the lettering is slightly raised, why it's slightly pixelated (as the laser will be directed to individual spots), and why the process is described as ‘laser etching’.

If so, it means there's no danger of the lettering coming away — it's not separate, but part of the same plastic mass as the rest of the key.  And there's no dye, ink, or paint to fade or separate.  The discolouration isn't from any permanent deterioration, but as you say, can only be from finger grease and/or other dirt.  This means it should be removable — though the rough surface of the letters might need chemical rather than physical means to get it all off.

So all we need to do now is to identify the best way of cleaning the keyboard!  Since we don't need to worry about dissolving any dye/ink/paint, just the plastic itself, I guess a wide range of cleaning agents might work.  Anyone care to try some??

(The main caveat is of course that the keys need to be removed first.  The preferred method I used on Psions still works, which uses a big blob of Blu Tak: press it firmly onto a key, then lift it off sharply.  If you get it right, the key top comes up with it — with much less risk of damaging anything.)

This has become a very interesting topic

[Dixit]

this does look as if not the "printing" is worn of, but it is just darkend by absorbing oil from the skin of the fingers.

Mmm, that could well explain it.

It actually looks like a tiny micro 3D printing.

Yes, it does.  Of course, actual 3D printing wasn't available 20 years ago when the Psion 5 was made, which is why silk-screen printing (where the ink/whatever is forced through a fine silk mesh) seemed a possibility.  Ink-jet-style printing (which is what 3D printing was based on) could also result in something like that.

However, videos such as these definitely show lettering being created (in impressive style!) by laser.  And that's apparently the standard way for keyboards, especially when they're not in long production runs.  (Other methods are ‘double-shot’ moulding where the lettering is in a contrasting colour of plastic, and dye-sublimation printing.)

I haven't seen a good explanation of laser engraving, but I suspect that the laser heats the plastic, causing it to expand and discolour (perhaps in the same way that soft plastics can change colour when bent/stretched).  This would explain everything: why the lettering is slightly raised, why it's slightly pixelated (as the laser will be directed to individual spots), and why the process is described as ‘laser etching’.

If so, it means there's no danger of the lettering coming away — it's not separate, but part of the same plastic mass as the rest of the key.  And there's no dye, ink, or paint to fade or separate.  The discolouration isn't from any permanent deterioration, but as you say, can only be from finger grease and/or other dirt.  This means it should be removable — though the rough surface of the letters might need chemical rather than physical means to get it all off.

So all we need to do now is to identify the best way of cleaning the keyboard!  Since we don't need to worry about dissolving any dye/ink/paint, just the plastic itself, I guess a wide range of cleaning agents might work.  Anyone care to try some??

(The main caveat is of course that the keys need to be removed first.  The preferred method I used on Psions still works, which uses a big blob of Blu Tak: press it firmly onto a key, then lift it off sharply.  If you get it right, the key top comes up with it — with much less risk of damaging anything.)

This has become a very interesting topic

I kind of understood (laser) etching otherwise. The plastic is to be etched and then a dye is inserted into the groof.
So you actually can clean away the letter.

Who dares ? ;-)

[Eldkatten]

Hello,

(...)Anyone care to try some?? (...)

Interesting indeed :-) And I was curious... So I tried, not on my precious new Gemini, but on my precious old Psion 5 mx. Pryed off some of the worst "worn" keycaps, and washed some with detergent and applied then isopropanol, on others I used only isopropanol. With the same result: once the isopropanol residues (the ones I couldn't get off with kitchen tissue) dried off, the keys look nearly as new. Which is quite a spectacular result considering that the whole procedure took only a few seconds per keycap. If applied more thoroughly, this might be a way to realy refresh the key labels.

Not that I want to do this very often, because I'm worried about that the keys might become loose if removed and snapped back on too much. Actually I think I won't clean the Gemini keyboard in that way at all. I never cleaned the Psion keyboard, and I never had to search for a key because I couldn't read the labels.

Because they don't "wear off".

Kind regards