Okay, I was being sarcastic. But I ran into this today and had a good laugh:

nvidia 7800 wont work

i bought one of these and tried putting in my dell dimension 2350. my friend said that the shiny metal part on the bottom looks like it has lines because you cut at the lines if it doesnt fit. so i carefully cut off the bottom so that it fit into 1 of the slot things in my computer. now it doesnt work. did i cut it wrong? id post pics, but no camera. is there anyway i can fix this? thanks for any help.

ouch…
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The Stirling engine, invented in the 19th century as an alternative to the steam engine, is powered by the expansion and contraction of a gas as it is alternately heated and cooled. In a conventional Stirling engine, the heating and cooling is achieved by moving the gas between a hot chamber and a cold chamber. The result is an extremely efficient mechanism that can operate on very small temperature differentials (i.e. body heat vs. environment).

The lamina flow engine is a Stirling engine with a single chamber with a hot end and a cold end, insulated by a restriction in chamber diameter. Not only does it have a much simpler design, but it is also somewhat more efficient: the only moving part is the piston.

It would be interesting if lamina flow engines can be used to harness solar energy the same way these guys are doing in L.A. with traditional Stirling engines.

I will be constructing a simple model using a test tube and a glass syringe. Details will follow as they become available.

I’ve been thinking about homebrewing a scanning tunneling microscope for a couple of years now, since finding out that it was possible. However, I did not have the engineering expertise to actually pull it off. Conceptually, the device is very simple. Basically, a sharp conductive probe is passed over a conductive sample, a voltage is established between the probe and the sample, and the tunneling current is constantly monitored. Using an STM, one can image a conductive surface down to the atomic level.

There are several challenges for the average hacker. The most daunting is that because nanotechnology is such a young field, one cannot just Google for this stuff and find usable plans for STM construction. I have found several potentially useful websites; since none of them describe workable projects with reasonable detail, I’ll be using them for ideas only. However, I intend to document this project as well as I can, for the benefit of future hackers of nanotechnology.

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The baby railgun was fired for the first time tonight. I was surprised that it actually worked, being so tiny. It’s also horribly inefficient. At the moment, it’s a hot rail type railgun, which means that the rails are energized before firing, and the projectile completes the circuit when injected into the barrel. Currently, I use a bamboo toothpick to push the projectile into the barrel. There’s a problem with that — because my hand is relatively slow, the moment any part of the projectile contacts the rails, that part is blown off, leaving the rest of it behind. I can certainly use compressed gas to inject the projectile, but that defeats the purpose of having a small and cheap demonstration railgun. The other choice is to use a neutral rail design, and use a switch to close the circuit. The switch would be exposed to sparks and arcs, so it would not last long.

That’s enough talk for now. On to the pictures!

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So… I broke another blade today. I really need a bandsaw… oh, well. But the beauty of this project is that it can be done without power tools, just not as quickly or neatly. I hacked out a couple of rails from an aluminum busbar, sandwiched them between microscope slides for heat resistance, and sandwiched the resulting unit between acrylic sheets for impact resistance. The whole assembly was held together using a couple of binder clips, so it can be taken apart easily and serviced.

The rails were 3.5″ x 0.5″ x 0.125″ and placed 1/16″ apart. The microscope slides were 3″ x 1″ and just enough to cover the rails and let 0.5″ stick out for the electrical connections. The acrylic sheets were 3″ long and wider than the microscope slides; this makes handling the barrel safer, because no metal is exposed at the sides.

Now the only thing I’m worried about is unwanted capacitance forming between the metal binder clips and the rails. We’ll see how it goes.

Its time for pictures!

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