Monday, June 15, 2009

more light stuff

A 1 hour ride showed no signs of heating on the lamp.

Run length should be 5 hours, unless I calculated something wrong.

Also worth noting, a similar output NiteRider lamp (110 lm) costs $130, compared to the $10 driver + $8 LED + 3$ optic + 2$ PVC + 10$ niMh batteries.

cheap and easy bike light

I built a cheap and somewhat easy bike light for my new twenty year old KHS bike. The design principles were:
1)Relatively bright
2)Efficient
3)Small
4)Lightweight
5)Low power
6)Makes me a sammich

I came up with this: 350 mA micropuck driving a Cree XR-E R2 bin ( a bit brighter than q5 bin, so 114 or so lm). I decided to use the same plastic lens that I used for my previous headlamp, and bought the R2 pre mounted on a star from DealExtreme (it took AGES to show up, as usual, but their support is ok). I'm still working on what to do with the battery back, but this is what I have so far:

1)use hole saw to drill handlebar radius hole into a PVC angle

2)Drill holes at the front and rear for zip-tying

3)solder together micropuck and star
4)cut slot in side of angle,insert metal washer (I actually used a random piece of metal from one of our Ikea dressers that was left over)
5)Bond star to washer with thermal adhesive: thin layer only, as usual.
6)Figure out some kind of removable battery pack: I ripped a plug out of an old nonfunctional wifi router

7)Mount to handlebars with zip ties, and small piece of rubber. It's the same idea as mounting a bike computer, for example.

8)Here's a shot of the plug


The shoddiness of the plug is purely to dissuade someone from stealing such a fine piece of hardware, and NOT because I am a disaster with a soldering iron.

The light is plenty bright, and no word yet on battery life or heating issues. The heating is a typical problem with these high power LEDs, but I have going for me: low current (350 mA), relatively large piece of metal bonded to the star, small gap around the lens through which air can flow.

zoe's new trick

Zoe has always loved baths, and is very unwilling to leave once she has started splashing and carrying on. Recently she figured out that when we started draining the tub, it meant it was bath exiting time... so she figured out how to stop the tub (a few seconds after we start it). I thought that was exceptionally clever, but I'm sure that's just daddy brain.

The KHS

I bought a used KHS as an around-the-town bike last month. It's a vintage lugged steel frame built in Taiwan, and a biking guy tells me that KHS are probably as well built as the vintage Raleigh frames, but easier to find. I picked mine up for $150. I had also recently tried a few single and fixies and loved them, despite the hipster stigma. I guess it's kind of like buying a BMW: they are great machines that drive well, but you look like a douche in one. ANYWAY, I decided that the old components were not really worth having adjusted, since they would probably constanly need tweaking, so I had Montano Velo convert it to a single speed, swap out the hobbit sized handlebars and do a few other modifications. The biggest cost was the new hand built wheel. They finished it on Friday, and I picked it up yesterday, and it is so, so sweet. It's an amazingly plush ride, and the drivetrain feels supernaturally responsive and direct. The only problem for Montclair milk runs is the hill going back up to our house.



The shop also has an amazing selection of Pegoretti frames, which are lustworthy. I guess they know Dario personally, and have carried his frames for years. They even had a freakishly beautiful lugged pegoretti frame in a glass case. I thought he only did welded frames, and don't really want to know how much that one costs.

life in Grenoble, France as an expat postdoc
life in Grenoble, France as an expat scientist
life in San Francisco, CA as a biotech nerd life in Grenoble, France as an expat scientist

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