deskthority

Hey guys,

My apologies if this thread has already been discussed, but my heavy-fisted google and DT searches yielded absolutely nothing. I've got an F AT that I am trying to open and cannot seem to find the correct driver size. I have the 5.5mm from my model M but that is too small. I read somewhere vaguely that it 'may' be 7.5mm (metric because I'm living in Germany). There seems to be not a single place where i can buy a 7.5mm driver (Can only find 7mm or 8mm) - let alone a slim fit one to fit into the recess. The closest I can find is purchasable online but it is 7.9mm and i do not know if it the head will fit in the recess.

Since many of you have done the AT restore/opening it up, would really appreciate it if someone could give me a correct size/sizes that would fit my AT screws. It's been days now that I've been trying to get it open and I have already spent north of 40 USD buying different drivers to no avail

You need something like this....
https://www.amazon.de/dp/B00TGUB52C

60mm

Ah yeah I think this should fit in the recess, however just noticed that it is 6.5mm. Is that the correct size?

Just checked my bit, yes.. 6.5 mm should work

Thank you so much! You're awesome. I'll run out and buy a bit today and hopefully get mine opened!

And alas - no 6.5mm drivers to be had in Germany either. Would a 6.3mm driver work by any chance? :/

Well, why not bring the board to the local shop and give a shot directly?

What nut are you trying to remove? My F AT only has screws in them...

Was trying to avoid lugging the board to the shop. Also, the shops here don't have much selection in this stuff. Most of this stuff has to be ordered online. @kmnov, my F AT has bolts like the Model M ones in the back, just bigger. I am not sure of the size in inches though, and cannot seem to find a 6.5mm bit.

Have a look at the pic I posted. Thats how my AT shipped with.

kmnov2017 wrote: 07 Dec 2019, 16:16 Have a look at the pic I posted. Thats how my AT shipped with.

Thats really lucky and odd, mine are standard bolts -

[/img]/img]

All right folks, Mu to the rescue!

Foreground: Model M SSK — gold coloured, recessed 5.5 mm hex headed bolt
Back left: XT — gold coloured, flush mounted large hex headed bot (>6 mm?) with handy flat screw cut
Middle back: Kishsaver — black, flush mounted circular headed 3 mm hex bolt
Right back: AT — silver, recessed, dome headed 2.5 mm hex bolt (3/32 inch also works)

The AT's bolts are recessed at least 1 cm from the case's outer surface. Just a smidge less deep than the SSK's.


Edit: Wait!? IBM really mixed and matched with the bots! That's your AT, right? Those bolts need a hex spinner, like a Model M. My kit of hex spinners maxes out at 5.5 mm…

Muirium wrote: 07 Dec 2019, 16:45 All right folks, Mu to the rescue!


IBM case bolts.jpg

Foreground: Model M SSK — gold coloured, recessed 5.5 mm hex headed bolt
Back left: XT — gold coloured, flush mounted large hex headed bot (>6 mm?) with handy flat screw cut
Middle back: Kishsaver — black, flush mounted circular headed 3 mm hex bolt
Right back: AT — silver, recessed, dome headed 2.5 mm hex bolt (3/32 inch also works)

The AT's bolts are recessed at least 1 cm from the case's outer surface. Just a smidge less deep than the SSK's.


Edit: Wait!? IBM really mixed and matched with the bots! That's your AT, right? Those bolts need a hex spinner, like a Model M. My kit of hex spinners maxes out at 5.5 mm…

Thanks for the specs Mu! Yeah that's my F AT, and I guess they were mixing and matching. These seem to be the original bolts as well. The 5.5mm Hex spinner for my IBM model M is too small for it. So I'm still not sure which size driver I should order :/ Also considering that whatever I order had to be online, each one ends up being 14-20 usd so I can't just order many of them and hope on one of them to work :/

Yeah, looks like you need something very similar to, but larger than, your Model M hex spinner. Ordering a kit would tempt me, but then I'd just be taking up space with tools I don't need. Ordering individual drivers and returning all those that aren't a match may be a smart choice.

The upside is those AT holes can only take bolts up to a certain size. My pic is shot on the back of my AT, so there's a bolt hole just at the edge of frame, at the right. Can't be too much larger than the 5.5 mm spinner, I think.

For what it's worth, my XT's bolts are a touch too big for my biggest hex spinner. Hard to measure with a ruler (I don't have calipers) but I'd guess they're 6 mm.

Conrad sells hex drivers individually for about 5/6 euros. If they don't work , you can return them.

So I just ordered 6mm, 6.3mm, 7mm and 8mm. I'm sure the 8mm was overkill but I'd rather return one extra driver than pay 6.50 Euros for delivery a second time. Hopefully should be here by tuesday. I'll post back with more info as soon as I'm able to try them out! Thanks for the info and help everyone