Talk:Disassembly

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Cautions

There seems to be some disagreement as to how prominent the cautions should be. I tend to agree with bernie.

If there are no comments on this for two weeks I will make some changes that encourage risk-aware disassembly.

MartinDengler 09:09, 29 March 2008 (EDT)

I think that it is great if kids are taking them apart, but, to be realistic, if every kid takes their own computer apart, some of them will break which wouldn't have other. Therefore, I think the wisest policy would be to say something like "if it breaks, take it apart and fix it. If you want to take one apart, find a friend with one they've already opened (because it broke) and have them show you how, or do it by yourself if you're careful and your friend trusts you." Homunq 11:47, 29 March 2008 (EDT)


Kimquirk 23:01, 29 March 2008 (EDT)
I agree that we need to encourage people to experiment since it provides a good learning experience, but the problem is that we also need to provide solutions for when the experimentation goes badly and they can't make their laptop work. What can they do? How can they get help? How can they get a part they broke in order to fix their laptop? Is it possible for them to buy a new laptop? Buy or acquire spare parts? Find a local repair facility? Download a pristine image to reload? If these questions haven't been answered, kids will be left with broken laptops, and OLPC will take (should take?) the blame for lack of planning.

As of today, we have sent out a couple dozen laptops to repair center hopefuls (mostly college age and above). They have agreed to help document repairs and train themselves and others to make repairs. A quarter of those laptops have ended in a more 'bricked' condition than when they started. We don't want to help people brick their laptops, right?

With any brand new product, before it has been handled by thousands of children, and with every new codebase that has not been tested for corner cases, error conditions, or stress conditions -- there will be problems. Once we get the feedback on items most likely to fail, and we have addressed items most likely to break during repair, then the XO will be much more robust to the screwdriver of the average kid. Today it is not. That's my opinion.

So Kim would you agree with Homunq's suggested wording? MartinDengler 07:26, 25 April 2008 (EDT)

Nicholas Bodley's comments

Nicholas Bodley (Started at) 03:07 EDT, 1 June 2008

I have to be careful what I say. At the moment, I'm a lot more interested in editing wikis such as these than updating my own user page, so this will be somewhat redundant. In brief, I've been involved in electronics for 66 years, if that counts for anything; I built my first radio in 1942. The field wasn't called "electronics" by everybody; it was better known as "radio" (technology, implied). Essentially, all my life, I have been very interested in electronics as well as small precision mechanisms. I've been a lab. technician, assembly-language programmer, repair tech., "electronic midwife", tech. writer, Associate Editor at Electronic Design magazine (for design engineers), one the first eight electronic desktop calculator technicians in the USA, semi-pro audio engineer, and more.

I did my first computer repair in the Navy -- it was a critical loose screw, but it took three days to get access. It was a mechanical analog fire-control computer. This was probably 1957, and for sure no later than Summer 1958.

I was one of the original computer techs on the BMEWS DIP at the NORAD COC in Colorado Springs, 1960 -- 1962. (Think PDP-8, but with a magnetic drum backup for core memory, and a 19-bit word length.) I was even a midnight hacker, with NORAD approval.

I hand-soldered a modest amount of surface-mount flatpack IC logic (Westinghouse 930 DTL) in 1964 in a development lab.

Along the way, as opportunity presented itself, I worked and played with small mechanisms; had a bunch of clocks ticking in the upstairs back hall in 1945.

I built a few Heathkits.

Perhaps one might say that I know something about electronics (and its history).

When I first learned that OLPC was proposing that kids do their own repairs, that seemed unbelievable. Apparently, it's true.

Kim has the right instincts.

First, repairs can include replacing the Geode CPU. That's possible, but it's such a highly-developed and critical procedure that only a few repair stations worldwide should do it, if even that. Offhand, I can't think of any repairs that kids might do other than replacing parts and subassemblies. With my background, we used to locate the bad part[s] and replace it/them.

Real repairs might even involve the use of a logic analyzer (Richard has a nice one). The thought of a youngster using one is fantasy land; if the kid is a budding Dr. Richard Feynman, and 10 years old, perhaps.

Of all the possible technical devices for kids to learn by disassembling and reassembling, the XO is one of the poorest choices, if one expects the device to work when reassembled.

VCRs have a lot of remarkable mechanism; especially if not working, I think those might be a better choice. Once the mainspring (and alarm spring, if any) are let down (controlled unwinding), a windup alarm clock is great.

Kids really ought not to do brain or eye surgery. Unless they are rare cases, they should not disassemble and try to reassemble a lady's mechanical wristwatch, or a pocket watch. They should not repair engine-control computers in modern cars, or automatic transmissions.

Kids like to play; after all, it's how they learn about the world. In regard to disassembly and reassembly, XOs are not toys!

Kids can be impulsive, sometimes delightfully so. Impulsive acts on an opened XO could "total" the motherboard.

Kids can be whimsical. They could do things that would make engineers have nightmares, in all innocence.

Kids can fight over possession of physical objects. OOps, just tore off the ribbon cable from the display. Oops, bent the heatsink, right at the thermal contact pad.

Kids have curiosity, God bless them. However, they tend to have little idea of the consequences of investigating something that could be regarded as very creative. As a curious kid, I got my finger stuck in a Christmas tree light socket -- 115 volts, too, thin skin...

Consequences of "innocent" actions can be little different from sabotage.

On an XO's motherboard is one IC (maybe more) with very closely-spaced leads. One accidental (or playful!) swipe of a screwdriver (or almost any other small object) could bend those leads, and they might break if some skilled adult with jeweler's no. 5 tweezers (common household item in the developing world) tried to fix the damage.

While it's possible that a careful, patient youngster with excellent dexterity would not have a lot of difficulty, properly supervised, as Kim mentioned, there was more harm than good done when adults tried to fix their own.

Static? Wrist strap?

Imho, it's a well-self-disciplined kid who reliably doesn't lose a screw.

Kids get into a fight -- one knocks the display onto the floor, and another steps on it unintentionally.

In short, kids don't yet have the discipline to work on a device that is both internally very delicate in places as well as being of quite modern technology.

I would not dare to reinstall a battery into an XO that had been opened up by a child. I don't know whether XO battery packs have internal fuses (maybe), but if they don't, Hallelujah!

What advocates of kids doing repairs apparently forget is that skilled adults fully qualified to do repairs have spent years developing the knowledge, discipline, and even instinct that qualifies them.

You don't know me (yet), so I ask you to take this on faith: I very rarely, in such matters as this, use strong language, but in summary, the idea of kids doing repairs is utterly nuts -- it's loopy, it's screwball, its New Age gone light years beyond goofy. OK, I exaggerated that last one for effect.

I don't have anything to lose, but I'd surely like to talk with Richard Smith and Wad (anyone else?) off the record with a solemn promise not to quote or reveal what they said, to see what they think. I'd suspect that they need to be rather circumspect.

However, there's always the other hand. Collect XO parts that are beyond economical repair, and assemble them into an XO that kids can take apart. Unfortunately, some housing parts aren't as likely to fail (or are they?).

I don't hate kids at all; I'm simply a realist who has some sense of what's appropriate. An XO is a very sophisticated, internally delicate device that will be destroyed by anything other than careful, informed handling.

(Btw, please don't consider this as a specimen of edited material, it's more a stream of consciousness.)

As a counterpoint: yesterday at 1cc, a 19-year-old taught a 12-year-old how to completely disassemble and reassemble an XO. The 12-year-old could have, if that XO had been broken, replaced the screen, keyboard, touchpad, etc. - this is a young person with no formal repair training, no electronics/computer background, nothing except a screwdriver in her hand. I've also coached - with my hands behind my back, never touching the laptop - kids as young as 7 to take apart the XO as their first experience disassembling a computer. Mchua 14:35, 1 June 2008 (EDT)
Nicholas, I agree completely that there are few if any pieces of hardware in the XO that a child should be expected to solder. But hardware repairs on the XO mostly consist of replacing descrete components, such as the entire motherboard or lcd. I do like your sense of not disassembling the XO willy-nilly. We should recommend that classrooms take apart an XO as a class to see the basics of the hardware.
But I think you underestimate many of our student's reverance of the XO. I doubt that the kids who put a towel down instead of setting the XO down on the ground would be so very careless with the XO's internals. But contriwise many children in the US are picking at the keyboard membrane until it falls apart.
I suggest some strong cautions, but no serious change to the content. User:Sethwoodworth

Things to change

Update this page to be more consistent with the repair guides linked from Repair. Possibly move Do-it-yourself Repair Options section on Repair to Disassembly and then route to the specific guides.

  • make this page more relevant to newer guides
  • add warnings on things not to break
    • add guides on how to do things with breaking
    • don't take out third screw under faceplate when removing it!
    • disconnecting cables - include how to do it without breaking it

Updated Dissasembly page

I've got Disassembly draft which is going to get tuned up and hopefully merged into this page tomorrow - any comments, tips, things we'd like to preserve, things we should archive? I will try to reuse as many of the comments and photos as possible. Mchua 21:32, 31 May 2008 (EDT)

videos and pictures

Greg Marra filmed Nikki Lee, Chris Carrick, and Tank Lai taking apart a keyboard. Raw files are here but something needs to be done with them. Mchua 15:28, 2 June 2008 (EDT)

Even younger: 7 year old and 4 year olds disassembling (wonder if we should have a "yes, kids can do it!" proof page).

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