Disassembly design

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Notes from Nicholas Bodley on dismantling an XO

I'm a retired electronic tech. (lifetime...) with more than average interest in design, engineering, and manufacturing. In recent years, I've opened up a number of typical laptops, so I've had a chance to see what typical insides look like.

As Mel dismantled, I was delighted to see how well everything fitted together; after all, an XO is meant to be dustproof, and closely-fitting major parts help.

One critical point, although not the most important, was a delight to discover: The screws fit into brass tapped (threaded) inserts that are molded into place. It's less costly to simply provide an undersized hole, and let the screw (more like a wood screw) deform the plastic. However, one has to be careful, when replacing such screws, to use the existing threads (IIrc, I gave Mel more info on that), or else the plastic in the hole becomes "chewed up" and the screw won't hold. (Procedure: Using gentle pressure, turn the screw backwards until you feel a gentel "click" as the threads align. Then, tighten it.)

Many other details were very nice to see. Nothing that I saw was done cheaply.

Although I haven't seen the insides of the latest laptops, I feel rather confident in saying that the insides are made as well as those of, say, a $1,500 laptop, if not even more costly. The insides are anything but junk!

It occurs to me that Quanta must have well-established design (?) and manufacturing standards and procedures intended for regular (= relatively costly) laptops, so the XO benefits from those; economies of scale are beneficial, here.

The AMD Geode CPU is attached and connected by a ball-grid array; that's definitely high tech! Afaik, analyzing connection quality requires x-raying.

Having spare screws (with their own brass inserts, as well, of course!) was a delightful surprise.

(Added by NB (nicabod), original author): After reading some initial replies, indeed, you folks are right! It is easy to disassemble and reassemble. (Easy assembly lowers manufacrturing costs, too. When one large printer company (IBM, iirc) redesigned its printers so they could be assembled by robots, they had all the pieces ready to assemble. Of course, first, they tried assembling by hand. It was so easy, they never built the robots.)

Btw, that metallic coating inside is metal; try the resistance range of your DMM. The coating might be applied by flame spraying.