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PowerBook 1400 Hinge Cracking - Has anyone found a fix?
Posted by: 3lectr1cPPC on 2022-07-01 17:28:44
The PowerBook 1400 series laptops are notorious for a different sort of hinge failure than the rest of the PowerBook lineup. Instead of standoffs breaking, the back display housing itself with form cracks around the hinges, which will get bad enough to cause the plastic to complete break. Unlike standoffs, this sort of damage isn't able to be cleanly repaired most of the time, leading to most of them looking like this ebay listing after a good bit of on-the-go use.

My 1400 is just starting to crack, and every time I use the hinge it gets worse. It isn't exclusive to this one model either, my Dell Latitude CPi has the exact same issues, and I'm sure any other laptop that uses this hinge design does as well. The CPi's situation especially sucks since that one's got a working battery. I used to take it out of the house all the time until this problem came about.

With the 1400 being a reasonably popular machine among collectors, has anyone found a permanent fix yet? It's the one Achilles heal of this system, it's perfect in just about every other way.
Posted by: LaPorta on 2022-07-01 17:49:00
I asked Maceffects once if he thought that it would be worth it to try and remanufacture them, and he wasn't convinced. I managed to find a display housing with no cracking at all, and I am keeping it in case we need one as a template somehow to make new ones.
Posted by: 3lectr1cPPC on 2022-07-01 19:16:44
I'd definitely buy one at some point is they made one - I hear their stuff is top quality, and I'd love to combine the new back case with a battery rebuild and take it on the go as a workhorse sort of system I don't have to worry about breaking.
Posted by: LaPorta on 2022-07-02 08:07:11
Battery rebuild is pretty easy; I've rebuilt three so far.
Posted by: 3lectr1cPPC on 2022-07-02 09:00:44
What cells did you use? I've got my old pack taken apart. The old cells were leaking but I saved the electronics, I just need the type of cells and I can buy some tabbed ones and rig up a new pack.
Posted by: CircuitBored on 2022-07-02 10:40:34
I just need the type of cells and I can buy some tabbed ones and rig up a new pack.

I'm in the exact same boat. I'm ready to rebuild - I just need a source for the cells!
Posted by: LaPorta on 2022-07-02 12:07:10
Either of these will work. One is higher capacity than the other. You need six of them. The battery type is 4/3 A. Make sure you get the flat top: if you get the ones with the button top, they won't fit. If there is a Batteries Plus near you, they will even tack weld on tabs for you identical to the original pack. You just need to bring the pack to them. I am sure another battery house would do the same.

Posted by: 3lectr1cPPC on 2022-07-02 12:22:59
Thank you! It will probably be a while but I will check out batteries plus for sure!
Posted by: LaPorta on 2022-07-02 13:02:35
Sorry, I meant to say you need 8 cells.
Posted by: galgot on 2022-07-05 07:42:04
About the hinges, there is this try by @AEChadwick :
But I haven't seen the final result once installed in the 1400c. And don't have access to a 3d printer the moment...
Posted by: sjgrall on 2022-07-05 08:54:00
I asked Maceffects once if he thought that it would be worth it to try and remanufacture them, and he wasn't convinced. I managed to find a display housing with no cracking at all, and I am keeping it in case we need one as a template somehow to make new ones.
I'd buy one if it became available!
Posted by: AEChadwick on 2022-07-06 19:01:50
About the hinges, there is this try by @AEChadwick :
But I haven't seen the final result once installed in the 1400c. And don't have access to a 3d printer the moment...
oh hey, forgive me: i never posted any "after" shots, i guess because [after] was just [powerbook that could hold itself open].

i know exactly what @3lectr1cPPC is saying... here is the lid that inspired my original effort. I’ve glued this same shim into three powerbook 1400 at this point, and they're all doing fine.
Posted by: 3lectr1cPPC on 2022-07-06 19:09:40
Thank you for the reply! My worry is that installing the shim won't do any good when mine is already starting to crack. If it prevents the issue on an uncracked panel, that's great. I just have trouble seeing how it will stop the issue on an already cracked panel.

Edit: Here's the state of my back panel right now. The metal hinge itself is very strong, with extremely little play, while also not being at all stiff. The metal part itself is in excellent shape, just the plastic is failing.
IMG_3359.JPG
Posted by: AEChadwick on 2022-07-06 19:32:38
Thank you for the reply! My worry is that installing the shim won't do any good when mine is already starting to crack. If it prevents the issue on an uncracked panel, that's great. I just have trouble seeing how it will stop the issue on an already cracked panel.
those cracks are godawful, mine went all the way through--there was no way to even open the lid--i shudder just remembering it.

there was no way to repair that cleanly, so my goal was get mass behind the area & spread that mass out as much as possible. (that's why the sprawling shape and profile and little ribs and stuff.)

I pulled the upper case off, flattened it out, then used lots of blue painter’s tape on the outside, to hold everything in place and prevent any leaks... because the next step was a thick layer of Weld-On 16 + Shim + clamps.

Honestly, this was not a dainty attempt to transfer stress-and-structure--this was "fill the case with more plastic" and re-assemble. This shim demands being glued in.

Upon removing the tape, some cracks were still hairlines... i used a pin to get glue into them, just to fill everything with as much plastic as possible.

I will post a picture of that top case when i get home; it's not pretty, but it has character, like something out of "Hackers," like the scars of a Kzinti Warrior. And it has remained solid, no movement, no further degradation.

totally not trying to sell you a bill of goods! just explaining my process and results.
Posted by: galgot on 2022-07-07 00:52:34
oh hey, forgive me: i never posted any "after" shots, i guess because [after] was just [powerbook that could hold itself open].

i know exactly what @3lectr1cPPC is saying... here is the lid that inspired my original effort. I’ve glued this same shim into three powerbook 1400 at this point, and they're all doing fine.
Thanks 🙂
Posted by: LaPorta on 2022-07-07 02:29:13
I may indeed try this if I can find a local printer.
Posted by: AEChadwick on 2022-07-09 06:43:41
after shot with battle scars. (kapton tape because i busted a clip inside that hinge and haven't printed a fix yet)

(before repeated below for contrast)


IMG_1773.jpeg
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