95LX exploding hinge

[Dave Britten]

This has me both perplexed and perturbed. I've got a pair of 1 MB 95LXes, and both of them within the past year have blown out the right hinge. This isn't the usual stress crack that develops on the 200LX, rather the outward force of the spring inside the hinge has cracked the plastic and caused the hinge assembly to start decompressing outward. In other words, they work fine if you don't mind the screen laying completely open and flat due to lack of a right hinge... Is that a typical problem with the 95LX? Kinda weird that essentially the same thing has happened to two of them within such a short span. I've got another one on the way, so hopefully I won't make it three...

[rprosperi]

I recall that on the 95LX, one side (hinge) tended to fail far more often than the other side, though no memory if it was the right, or this failure mode. I didn't own a 95LX at the time, so I was not in the loop, I just remember hearing murmuring about the problem.

[Dave Britten]

Yeah, the right hinge is where the failure normally happens, since that's where all the spring tension is. The left hinge is little more than an idler. But I can't say I've ever seen one blow the hinge out like this - it's usually stress cracks on the back of the case like you see on the 200LX. So to have this suddenly happen to two units is puzzling.

[Uli]

Strange things happen. Today I picked up my beloved HP200LX (4MB) to put in new batteries. In the process, I noticed two breaks on the back. I suspected it was because of the Eneloop, which are very tight in the battery compartment. I thought they were longer than normal Varta alkalines. But: eneloop = 50.35 mm and Varta = 50.55 mm in length.

[Helix]

(11-02-2021 12:28 PM)Dave Britten Wrote:  This has me both perplexed and perturbed. I've got a pair of 1 MB 95LXes, and both of them within the past year have blown out the right hinge.

I've had the same problem with one of my HP 200LXes. So now I have a spare spring and small parts from a broken hinge. Nothing is visible with the hinge cover.
The most puzzling thing is that there is still a good resistance when I move the screen part, as if there were no break at all!
I have another HP 200LX with the classic crack near the hinge, so I know the difference.

It seems that the plastic used for these machines brittles over time:
https://www.youtube.com/watch?v=8wLD24qZpiI

[Dave Britten]

(11-05-2021 12:20 AM)Helix Wrote:  

(11-02-2021 12:28 PM)Dave Britten Wrote:  This has me both perplexed and perturbed. I've got a pair of 1 MB 95LXes, and both of them within the past year have blown out the right hinge.

I've had the same problem with one of my HP 200LXes. So now I have a spare spring and small parts from a broken hinge. Nothing is visible with the hinge cover.
The most puzzling thing is that there is still a good resistance when I move the screen part, as if there were no break at all!
I have another HP 200LX with the classic crack near the hinge, so I know the difference.

It seems that the plastic used for these machines brittles over time:
https://www.youtube.com/watch?v=8wLD24qZpiI

That's my big fear, that these old plastics are just generally becoming too brittle to be viable as carry-around devices. Hopefully I'm just being paranoid... I need handheld Lotus 1-2-3 and databases!

[Dave Frederickson]

Several years ago a small piece of the right hinge on my 200LX exploded off with enough force to knock the hinge cap off. Luckily the hinge still works fine.



Dave