HELP identifying mystery screws on my T42- Pictures included

[memoboy]

I noticed a screw had fallen out of the bottom of my American T42 but when I looked underneath I saw two empty screw holes.



1. Can anyone identify where this screw belongs?





2. Does anyone know if the upper screw hole is normally empty and what it's for? I've circled the two empty screw holes, the lower one is obviously for the hard drive.





Here's a close up of the upper screw hole:





Here's a close up of the lower screw hole for the hard drive:



Click images to view at full size.

Thanks for your time

[rkawakami]

G'day and welcome to thinkpads.com!

The "upper" screw hole is the one which holds the Ultrabay drive inside the bay. It's normally known as a security screw. Based on the looks, the loose screw may have come from there. All of the other screws on the bottom of a T4x are smaller.

[poshgeordie]

Hi

The screw goes into the bottom hole in your pictures and is used to hold the Hard Drive Caddy in place.

You may also want to look at this document which shows where all the screws on T4x go.

I've just noticed that the HDD caddy screw is the one screw NOT on the diagram!

[Mike Blake]

I can verify what the gentlemen above say, not because I know half as much as those Thinkpad experts, but because I happen to have that very screw from my T42 in front of me as I type this!

Working on a hard drive problem, I took it out so many times (putting it in another PC, putting it into an external enclosure, etc.) that I stopped using the screw while doing this, and forgot to put it back in the last time. I still have it sitting here. That's definitely what one it is.

Don't know why or how, but checking this just now I noticed that by coincidence the bottom is also missing the same security screw you are.

Definitely check out PoshGeordie's useful diagrams, by the way.

[memoboy]

Thank you very much for all your replies. Does anyone then have a picture of the screw that's for the the upper screw hole (the UltraBay/CD drive)? I for the life of me don't ever remember it being there or what it looks like.

[Nick Y]

...Working on a hard drive problem, I took it out so many times (putting it in another PC, putting it into an external enclosure, etc.)...

Just a word of warning. The plastic fascia cover of the hard drive has two angle brackets that fit onto the hard drive caddy. I have never undone these brackets -they have a securing screw, but I assume no loctite -although I have taken out the drive a few times from the T41p, i.e when I changed the drive.

The T41p suddenly shut down a couple of days ago for no expected reason and would not restart. I took out the hard drive to check it externally and found that one of the screws had gone and I suspect, although not confirmed as I cannot find the screw, that it may have been related to the death of the motherboard. The screw can only have been there when I last put the drive back in place. (BTW, I am not sure about the actual screw size, M1.5 or similar, but an 8BA does the job!)

I now await a replacement motherboard before I investigate the existing board. (Fan works; LEDs come on; 1 3 3 1 short beeps when DIMMs removed; Lenovo replaced board a couple of years ago for GPU related failure, so could be just a fuse...)

[poshgeordie]

Done a bit of measuring and the CD security screw you'd need seems to be an M3 x 4mm long pan (flat) head.

Personally I've never seen or used one since the CD drives don't fall out usually!

[dr_st]

Personally I've never seen or used one since the CD drives don't fall out usually!

When you buy a new Thinkpad, this screw comes in a small plastic bag along with the rest of the accessories.
I've never used one myself. It seems it may be more useful for preventing someone from stealing the CD drive (say from a laptop locked in a dock) than for preventing it from falling out on its own. Although, surprisingly enough, it did happen to me 2-3 times (CD drive became loose and fell off while the notebook was in a backpack).

[tim S]

The hard drive security screw and the CD/DVD security have the same thread.
The CD/DVD screw might look a little different but the HD screw will do the job.

Tim S