Cooling a notebook computer on a deadline

2013/04/27

Thursday 10pm knew this notebook computer fan is dying, way noisy. By 11pm knew a warranty replacement would be here Monday at best [got here Wednesday]. Working on a different computer would have been daunting. How to keep this one working?

Tried to install software to control fan speed, maybe avoid resonance frequencies. No luck despite several related utilities such as GNOME Sensors Applet, fancontrol, and dellfand (found via I8kfanGUI). Reading the fan speed was possible, controlling it wasn’t. Went to sleep.

Friday morning decided to blow air through the computer with a fan we had made for breathing clean air when soldering: An old computer fan on a cell phone charger. Apparently a blade had broken, so it was rattling too much. Time to make another one like it.

Found fan on motherboard on kid’s bookshelf. Ran it from adjustable power supply to find right voltage for reasonable fan speed. For a 12V DC labeled fan that was about 7V. Found a leftover power supply 6V DC. Verified with multimeter it did output a voltage matching its label, verified with adjustable power supply 6V would spin fast enough. Cut wires, soldered wires, hot glued and electrical taped it up. Grabbed leftover lumber and kids’ building blocks and stuck it under the notebook, aligned to blow where the built-in fan should blow.

notebook external fan

Making a Notebook External Fan

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Internal-gear hubs on bicycles

2013/04/16

Before there were derailleurs there were internal-gear hubs. I was brought up appreciating the low maintenance needs of Sturmey-Archer 3 speed hubs. Around 1999 I couldn’t get one where I lived, ended up riding a Shimano Nexus Inter 7-speed. That 7 speed is dead now in 2013, a can of metal shavings, possibly worsened by unwisely riding it under water this winter. This creek hasn’t stopped me yet, but after hydrolocking a truck engine around 2003 it contributed to an early demise of my hub this time around – same creek, different crossing. For me to learn limits.

Now I’m working on replacing the hub with a NuVinci brand continuously variable transmission. Fascinating different mechanical design. I did not see it coming. Reviews by owners seem to be positive. Putting it into my existing bike. We’ll see how that performs, ask a few months from now.

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