IBM Model F screws

nfc

29 May 2012, 06:36

I recently got an IBM Model F. Feel and click is even better than the Model M!
Now it's time to clean it carefully....
I thought that screws on the back should be 5.5mm as the model M but they aren't.
It's sure not metric eigther, because the M6 hex-screwdriwer appears to be too little, while the M7 too large.
Have to be 1/4 or something like this.

Could somebody confirm?
Do somebody knows an online store where to get it?
I was googling around a little but without many results: I'm searching for a slim one, because the screw is placed in a hole... a too large key will not fit there inside.

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Peter

29 May 2012, 11:09

Model M screws are actually 7/32" (5.5563mm)
Next size is 15/64" ( 5.9531mm) then it's
1/4" (6.3500mm)

Yes, you need a 'slim' nut-driver, like this one :
http://www.clickykeyboards.com/index.cf ... /id/105901
and I think it's a 1/4" you need for a F, but I may be remembering wrong, it's been A LONG time since
I had a F to disassemble ..
You can find them at online electronics-suppliers like mouser or at professional tool-shops.
1/4" shouldn't be a problem, the 'slim' may make it a bit harder to find it.

ripster

29 May 2012, 16:05

I still think the Model M is 5.5mm.

Show some Metric pride!

JBert

29 May 2012, 16:36

The model F PC keyboard and model F PC AT use the same size of hex nut as a computer case screw. I opened mine using a hex driver in which I normally plug bits for flat or cross screws.

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Peter

29 May 2012, 18:44

ripster wrote:I still think the Model M is 5.5mm.

Show some Metric pride!
If you take a closer look you will notice that they are in fact BOTH 5.5mm and 7/32" !
The sides of the head are slightly angled, so both metric and imperial tools work .
IBM-engineers really knew their shit !!

I'll only charge you one farthing for that info (1/4 penny or 1/960th of a pound Sterling) .
If you like, I could convert that number into old Danish units, using this :
frontsmallnew.jpg
frontsmallnew.jpg (69.93 KiB) Viewed 4505 times
;) ;)

nfc

29 May 2012, 19:04

OK... for Model M it is clear: M5.5 or 7/32" this I understood well now :)

What about Model "F" ? 1/4" ?

I found it on Mouser as Peter suggested: it's 4€.... + 20€ shipping... you will understand that I really need to be sure, before putting 24€ on a nut-driver :D

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Peter

29 May 2012, 19:10

Yeah, I bought a complete set, just to get the 7/32 !

It's been at least 10 years since I had a 'F' to disassemble ..
Embarrassing, but I don't remember the exact size !

If ripster can let go of his Lego's for a brief moment it shouldn't be a big problem to find out for certain ?
(thinking about it, this should be required specs in wiki-articles, shouldn't it ? It actually matters for us !)

PS !
Once you get inside :
Does it have plastic-rivets ?
IIRC the 'F' was 'born with bolt-mod' .. That would partially explain why it feels more 'solid' ..

nfc

29 May 2012, 19:20

Yeah, I bought a complete set, just to get the 7/32 !
Really? In this case... would you mind if I ask you to ship me the rest of the set?
;) You can keep the 7/32", I however own a M5.5... ah ah ah

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Soarer

31 May 2012, 21:33

Surely you can find one closer to home, with less postage!

What I haven't been able to find is a cheap set that has both 1/4" and 7/32". I'm using the 1/4" driver from this set (it's a bit too chunky really), and the 5.5mm from this set.

This Nielsen set has 1/4", looks fine, and pretty cheap. Dunno if you can get those in Italy. Farnell has a 1/4" for just under €10.

What's the Italian for 'nut spinner' or 'nut driver' anyway? :?

nfc

02 Jun 2012, 10:46

Soarer, thanks a lot for the links. :)
There are severall ways to indicate in Italian the nut-driver: "cacchiadadi" (nut remover), "chiave a tubo" (tube key), "giradadi" (nut twister).
But Googling for it is a little complicated: almost all results are metric. If I try to refine the search by indicating 1/4', results returns removable insert keys, where the 1/4 is the size of the nut insert attachment. And moreover that type of key will definitively not fit in the little hole where the screw are placed, need therefore a fix one.

I just wanted to know if 1/4 was the right size, but you indicated me where to find a complete set in EU, so even if it not, I'll however own the right key.

ripster

02 Jun 2012, 15:35

All this Italian while enjoying an espresso is lovely.

However " nut twister" gave me pause.

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