Mirror finish Model M plate?

[theferenc]

Has anyone else come across a mirror finish plate in their Model Ms? I just picked up a 1987 1391401, and the plate has a mirror finish on it. Every other one I've come across has been just a dull matte steel look to it.

[DaemonRaccoon]

Pictures would be nice. Mine is the dull matte steel.

[Daniel Beaver]

I've opened up many Model Ms, and have never seen anything like that. Pics?

[theferenc]

Yeah, I know, my battery is charging. Pictures forthcoming, with a comparison to a "normal" plate.

[PlayerZero]

It's because mechanical keyboards are so expensive.  If you get into them, there's no way you have money to spare for something as trivial as a mirror.  IBM is smart.  

[theferenc]

Here we go:

[PlayerZero]

Shiiiiiiiinyyyyyyy!

[theferenc]

Yeah, I thought it was weird. Hence this thread.

[DaemonRaccoon]

That looks awesome! Not quite mirror finish, more of a chrome-plated look. Still DO WANT.

[theferenc]

Well, it is likely to end up for sale after I bolt mod it, so you might just be able to have it if you want.

[slueth]

are you talking about the second picture?   Model Fs has that finish also.

[theferenc]

The second picture? Well, it's the bottom plate, yes. The other plate is there for comparison.

[theferenc]

Oh, and for reference, it's a 7 May 1987 1391401 Model M.

And all the screws have a blue tint to them too. It's a very shiny Model M.

[PlayerZero]

Someone needs to make a keyboard entirely out of that stuff.  For now, that plate would make a good conversation piece.

[drsauced]

That is very odd, the steel looks to be tempered or bright annealed.

[dfj]

Reminds me of the thicker plate first Model Ms.

Not TOO rare I guess.

Yup - my early non-PS/2 M, and at least one other has the chromed plate. They are pretty, though - perfect for industrial-esque mods where it will show.

[The Solutor]

They are two different kind of zinc coating, the second one is usually easier to find on eastern products, but is just a trend not a rule.

[theferenc]

The inside of the plate is even brighter than the outside. Wacky.

[dfj]

yeah - I've seen other (F) IBM plates where the outer was bright nickel, overtop of zinc, then the steel... the nickel appeared to have a baked oil/oxide finish of some sort, not normal paint.
  That plate might well be nickel over zinc, since nickel plating is nearly as good at corrosion defense, but doesn't need to be tough like chrome since these plates are inside the keybord. the normal M plates are steel with just zinc, to my understanding.
  Easy way to tell, mind - is to scratch at it near a corner, or inspect any oxidized spots - bright nickel looks quite different to chrome when getting rust spots, doesn't bubble and flake off so nasty, etc...  when scratching, the nickel will scratch with stuff, while the chrome is very hard to scratch as it's crazy hard and pretty tough.
  I'll try to check on mine before anyone destructively tests theirs - mine is in rough enough shape to have many candidate locations to poke at.

[theferenc]

It scratched fairly easy when I was ripping off the studs. I tried to be careful, but I put a few scratches on it. I was using a fairly sharp chisel, but yeah, if it was chrome, it wouldn't have scratched so easily.

[dfj]

yeah - I found 3 relevant boards, only two were nice and shiny - my M was actually one of the shiny, multicoloured, but not smooth-mirror finished. it was simply nickel + zinc _ heat or oxide giving it a bit of rainbow action.
two F (XT type 1 and 2)  boards were very shiny, mirror-like, though - one being shiny nickel with a bit of rainbow from oxides etc.., but the other had none, even with corrosion. the way it had flaked at some wear points, though, made it clearly chromed. This was the type 1 XT, which is bloody uncommon (normal XT boards are type-2 and work with most IBM PCs, the Type 1, however did not have the uC in the keyboard, instead it was either in the cable between the PC and keyboard, or it was in a keyboard thing... unsure). It came with serial cable, but most of the wires are used as it is a parallel connection.

[The Solutor]

yeah - I've seen other (F) IBM plates where the outer was bright nickel, overtop of zinc, then the steel... the nickel appeared to have a baked oil/oxide finish of some sort, not normal paint.
  That plate might well be nickel over zinc, since nickel plating is nearly as good at corrosion defense, but doesn't need to be tough like chrome since these plates are inside the keybord. the normal M plates are steel with just zinc, to my understanding.
  Easy way to tell, mind - is to scratch at it near a corner, or inspect any oxidized spots - bright nickel looks quite different to chrome when getting rust spots, doesn't bubble and flake off so nasty, etc...  when scratching, the nickel will scratch with stuff, while the chrome is very hard to scratch as it's crazy hard and pretty tough.
  I'll try to check on mine before anyone destructively tests theirs - mine is in rough enough shape to have many candidate locations to poke at.

 
Is almost surely all zinc, which is cheap, effective and is less dangerous for the human healt.

Looks weird but zinc coating can look very different with slight changes on thickness, current applied during the electrolytic process, temperature, initial finish of the steel meant to be plated and so on.

It look usually as matte gray, but it can start from chrome look to golden to black depending on the production process

[ch_123]

Seems to be a common fixture of the first generation of Model Ms (from 85 up to about 88)

Some within in that time may not have them. It really depends.

[theferenc]

Odd, most all of my 101 key Model Ms are from that time span, though this is the first I've seen it.

I've got 3 more on the way though (I know, it's like a disease, but I do end up selling most of them), so we'll see what they present.

[DesktopJinx]

I wonder what it would take to mold a clear Model M casing.

[dfj]

some sort of resin, depending on what sort of optical clarity you were looking for, and a mold.

Typical technique for objects of such a size is to make the mold using paint-on latex, then cover that with fibreglass and resin so it holds the form well.
One might cast a few tests with fibreglass resin (without the glass) to get the hang of it, even though that resin usually has a strong yellow/brownish hue, and then do some with more expensive clear resin.

best luck.

[PlayerZero]

some sort of resin, depending on what sort of optical clarity you were looking for, and a mold.

Typical technique for objects of such a size is to make the mold using paint-on latex, then cover that with fibreglass and resin so it holds the form well.
One might cast a few tests with fibreglass resin (without the glass) to get the hang of it, even though that resin usually has a strong yellow/brownish hue, and then do some with more expensive clear resin.

best luck.

Now I'm wanting some amber keycaps.

[dfj]

Cute - what are you using to tint yer resin?

[jpc]

This is why steampunking a Model M is redundant.