Name of chassi screws?

The chassi screws on my librem13v2 are getting worn after opening a couple of times. I thought I’d want to buy replacements (ideally Torx, which as I understand are less prone to be worn).

Not being a screw expert, what is the name I should be looking for? It needs to be the right head type, length, and width. I see screws have their own vocabulary so I don’t know what my questions even are.

I’m referring to the external chassi screws on the bottom.

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Separate the driver type of the screw from the business end. The screw head determines what tool you can drive with. There are lots of screw head shapes, but yours are likely to be some non-countersunk type, and most countersunk styles are interchangeable as well as the non-countersunk variety. The shaft (business end) comes down to three measurements, length of the rod/cylinder, the diameter of the rod, and pitch of the threads. Typically there are only two pitches; fine and coarse. Corse is quicker for building, but fine is superior in holding power.

Any head can go on any threaded rod, so replace with what you want, but also it’s better to get ones for tools you already have. Take one to a local hardware store and see if they have them. Otherwise, try online.

Torx and Allen/Hex are related, also PZ/Posidriv and Phillips-head (cross-point) are related, but the first-mentioned of each is superior.

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if you are going to replace anything make sure to :slight_smile:

  1. properly and thoroughly document the disassembly process
  2. buy quality replacements
  3. there are some types of metal alloys that are more resistant to mechanical forces
  4. buy an automatic force limiter type of screwdriver if you are not sure how much or how little force to apply
  5. make sure you use the intended screw driver head
  6. make sure you KNOW HOW TO correlate correctly the screw driver head with the chassis screws.
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Also feel free to check the fine manuals.

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OMG! A left-side panel hyperlink for the screw specs! Flat-head countersunk, metric 2mm diameter by 4mm long and 8mm long. The head looks like ordinary Phillips instead of the PZ type. Probably why you can wear them out. Also, note the blue Loctite dab on the one side of the threads? Blue is for non-permanent thread locking, red is for never come apart thread locking. That blue is a material that causes them to stay in place under vibration and other problems that loosen fasteners. It also makes them harder to put in and take out, so wearing out the heads should be more likely. You’ll probably be okay without loctite on the replacement screws. :smile:

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perhaps it would be a good idea for Purism to include in the future Librem devices a dedicated Torx screwdriver like the one included in the high-end AMD-TR4 and up CPUs packages.

i’m sure they could earn a little extra from that too … as they market it as an easy to service-yourself machine.

maybe come up with some other ingenious way to solving the self-maintenance issue. screws are not necessarily the best option for this goal. though i don’t suppose many people losen and then tighten the screws on repeat all day long …

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Clearly there is a superior fastening tool:

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Awesome link with great photos and the names of the screws, thank you!

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:rofl: lmao

what was it ? if the only tool you have is a hammer everything else is a nail …

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Or a note to the technician stating that significant downforce (c. 5 to 8 lbs.) should be placed on the screwdriver while breaking loose the initial friction load of a tightened screw. :wink:

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