[HN Gopher] Repairing a tiny ribbon cable inside a 28 year old I...
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       Repairing a tiny ribbon cable inside a 28 year old IBM ThinkPad
       701c
        
       Author : jgrahamc
       Score  : 45 points
       Date   : 2023-03-11 18:16 UTC (4 hours ago)
        
 (HTM) web link (blog.jgc.org)
 (TXT) w3m dump (blog.jgc.org)
        
       | somat wrote:
       | A deserved "Well done" to the author, a good end to a tricky job.
       | I wonder if it is possible to solder the two halves of a flex
       | circuit directly together? That is, is it possible without the
       | junction wires?
       | 
       | Scrape the top of one, the bottom of the other, apply solder pads
       | to both sides then align the two and reflow the solder.
        
         | megous wrote:
         | That's how these are sometimes soldered to the PC board.
         | 
         | Eg. https://pine64.com/wp-content/uploads/2020/09/PinePhone-
         | USB-...
        
         | myself248 wrote:
         | Theoretically yes, but it's harder to control the heat for the
         | duration you need to do that. The flex substrate is pretty
         | melty.
         | 
         | I would try it with a shovel tip and a whole lot of spares to
         | get the technique down, but if I only had one shot, I think I'd
         | go with the author's technique, one wire at a time. Perhaps
         | with less gap between the ends, though.
        
           | jgrahamc wrote:
           | The gap was to make up for the amount of ribbon I'd damaged
           | along the way. I didn't want to shorten it too much!
        
           | neuralRiot wrote:
           | I've done this many times and in smaller ribbons with
           | narrower traces, this is a FPCB the substrate is kapton and
           | it should whitstand soldering temps pretty well the trickiest
           | ones are FFCs (the white ones)
        
             | myself248 wrote:
             | Oh good call, yes most of my experience is with the white
             | ones. Clearly I need to tinker more! :)
        
             | jgrahamc wrote:
             | Ah. Good to know. I actually attempted something like that
             | before this particular fix and it didn't go well. Hence I
             | "gave up" and did it the "hard" way by hand.
        
       | causality0 wrote:
       | _Amazingly that ugly thing has no short circuits and there 's a
       | connection on all six tracks. Clearly, that's very fragile so I
       | mixed up some epoxy glue and covered the whole thing up._
       | 
       | If you're going to do something similar I would suggest not
       | relying on just epoxy. Consider adding something like a strip of
       | denim as backing support.
        
       | whythre wrote:
       | Impressive work at such a small scale. I used to work with small
       | ribbon cables frequently, but it was usually some scraping and
       | reshaping to fix deformities- nothing as audacious as this
       | grafting!
        
       | jtwaleson wrote:
       | Awesome work, happy to see you're putting them to good use ;)
        
       | dm319 wrote:
       | Anyone know if it's possible to run a modern distribution on
       | this? I had a bit of difficulty running full-fledged Linux on a
       | Thinkpad X60 due to it being 32bit. Linux mint debian edition
       | came to my rescue, but I wonder if you'd need linux from scratch
       | or something like that.
        
         | cpach wrote:
         | NetBSD should work according to their docs:
         | 
         | https://www.netbsd.org/ports/i386/hardware.html
        
         | jtwaleson wrote:
         | It's a 486, you will probably be able to run a lightweight
         | Linux distro but it will be sloooooow.
        
           | doublepg23 wrote:
           | I don't think most distros compile for i486, minimum is i686
           | (not too familiar with the jargon though, before my time).
           | Even the kernel itself was going to trash i486 support
           | entirely. https://www.phoronix.com/news/Intel-i486-Linux-
           | Possible-Drop
        
           | guessbest wrote:
           | They'll have to run it with a 2.2 era kernel. Everything
           | after that ran dog slow on these machines.
        
         | cosgrove wrote:
         | Not quite what you asked, but there was someone who did a
         | "brain transplant" recently:
         | https://www.tomshardware.com/news/ibm-thinkpad-701c-receives...
        
         | qbasic_forever wrote:
         | Debian still has 32bit x86 binaries:
         | https://www.debian.org/distrib/
        
         | [deleted]
        
         | guestbest wrote:
         | There is a big slowdown from win98se to win2k, it is the same
         | on Linux with 2.2 kernel and the 2.4. You would best using an
         | older operating system, shutting down most of not all services
         | and connecting through a very strict proxy
        
         | luke2m wrote:
         | I run MX Linux on my T60.
        
         | opencl wrote:
         | The kernel itself is still fine on 486s and there are a couple
         | of distros that should still technically work. Obviously
         | nothing 'full fledged' is going to fit in the RAM on the thing
         | or run at any sort of reasonable speed.
         | 
         | Gentoo is probably the easiest mainstream distro to get running
         | just because you can fiddle with all the compiler flags and
         | kernel options. A few people have also put together small
         | custom images with modern kernels for this class of hardware.
        
         | haunter wrote:
         | Xwoaf-rebuild-4.0 http://pupngo.dk/xwinflpy/xwoaf_rebuild.html
         | 
         | One floppy image, full GUI and tons of applications through
         | busybox. Here is a video showing the full distro
         | https://www.youtube.com/watch?v=8or3ehc5YDo
         | 
         | On the other hand it's not "modern", 2.2.26 kernel is from 1999
        
       | [deleted]
        
       | CTOSian wrote:
       | It may be possible to use conductive paint instead of soldering,
       | of course this depends if there is allowance to keep the damaged
       | part flat. I did this on a keyboard membrane, had some damage
       | caused by water. You need to apply the paint slowly via a
       | toothpick, then kapton tape on the top.
        
       | archarios wrote:
       | I have an OP-1 that could use similar love on the ribbon cable.
       | pretty nervous to try it though..
        
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       (page generated 2023-03-11 23:00 UTC)