||[Apr. 1st, 2012|10:55 pm]
sprockets, sockets, grommets & gaskets
We pottered about the house, went shopping, pottered some more. I went for a nice long bike ride: out west, intending to go up Lookout Mountain, but I got distracted by the trail up North Table Mountain. I'd tried this once before when it was snowy and gave up halfway up because I was slipping more than I was going forwards. It turns out that when the ground isn't frozen, sandy gravel is just as difficult: 11% grade on a road bike is painful no matter what.|
On the way back down that bit I melted/glazed my front brakes, so the bike is hors de combat until I can refinish them. Hence, no Lookout Mountain, because having lousy brakes on that descent would kill me.
A couple km further, I was on a trail and took a sharp turn to see a big black line stretching across the concrete. I thought it was a crack until it went all slithery. It was a snake, over a meter long, and very skinny, a very dark green/black on back fading to a light green/yellow on its stomach.
It is possible I let out an alto yelp.
Cruising along by the Clear Creek watching people pan for gold. Fifteen people down in the river today. I came across two different people who had broken bikes and needed help: both flat tires with technical difficulties. One woman's glue container had failed, leaving her stranded, but she had everything else she needed. The other guy... he was trying to put a patch on his tire, rather than his tube. The patch he was trying to stick on there requires glue (and, y'know, doesn't go on the tire) but he was trying to stick it on without glue.
So I sat down and we went through a quick how-to-fix-a-puncture lesson. He'd also managed to pull the rim strip off the wheel, and had no idea what it was or where it went, and his pump, a cheap Schwinn, flat-out didn't work. ("I don't know what I'm doing wrong with these weird valves..." because he had Presta stems; I'm all "you're not doing anything wrong: this pump just doesn't work.") So I showed him why expensive European pumps are worth every penny and we went through sanding and gluing on a patch and he rode off happily.
I built a version of the rotary encoder board to fit inside a mini servo. It's stupid small, and I hate working on stuff this small. I particularly hate it when I don't have the right parts, so I have to fit on other parts that are a shade too large.
Most all the parts are supposed to be 0402 for clearance but I had to use 0603's because that's what I have. 0603 LED's are really physically weak: they come apart during soldering if you're not fast. Or, uh, if you load them the wrong way and have to rotate them.
That's pretty much what it looked like. This was within the city limits of Golden.
2012-04-02 07:39 am (UTC)
Why is it that expensive European pumps are worth every penny? I've never tried one, just use cheap pumps that move air from point A to point B.
Durability and availability of repair parts, mostly. I've had a Zefal hpx -- this *particular* hpx -- for 19 years and it's still working, despite having gotten run over by a car once. It's heavy, like nearly the weight of my racing bike's frame, but it appears to be immortal. And it fills up a tube in 1/3 the time that his 30-cm long, 1.5-cm wide pump would have taken had it worked.
1) regarding bike pumps I never found a hand one that was worth spit. Of course, I don't have a lot of arm strength. Mostly I rode short distances in town so it wasn't too big a deal.
2)I can believe that was some PITA soldering, but I don't see any LEDs on that board... am I just overlooking something?
There are two: labelled D1 and D2 at the bottom right, directly above the 'o' in servo. They're tiny little things.
Mobile bike pumps are a hassle. Some are less of a compromise: the longer they are the better they seem to work.
Ah, I think I see them now.
2012-04-02 08:30 pm (UTC)
Same one I have. It does work well, but it's not as convenient as a floor pump, and lacks a gauge. It also lasts 18 years and survives being run over by cars.
I try to avoid anything below a 0603 - and I have to do that under a microscope.
Me too. These days, now that I'm old and stuff, even 0805 is microscope work.
My poor coworker, who is designing power amplifiers for mobile telephones, gets to hand-solder 01005 stuff on occasion.
wrt dude patching his tire: he sounds about my level of bike l33tness. Glad you helped him out :)
It's always a learning process; I just encouraged him to the next level (and hope he'll keep riding.)
At first I thought (not having really read the technical details yet) that you were showing off learning to gild a quarter.
Is that actually a gilded quarter or just a trick of the light?
Trick of the light, alas. I suppose I could...
Heh, the wife of one of my coworkers works for him.
What they're trying to do is make extremely pure crystals of a niobium salt, because it has nonlinear optical properties. What they mean by that, is that it changes the characteristics of a beam of light passing through it, as some weird function of the amount of photons -- and by 'changes' I mean it can be tuned to shorten the wavelength by 2x or 3x, converting green light to UV -- or a number of other really weird things. I've worked in that field and it requires serious chemical processing facilities and probably a PhD in physics and a master's in chemical engineering even to work on the problem. Alas.
2012-04-03 08:22 am (UTC)
or a number of other really weird things
Phase-conjugate mirror! Spatula laser!
I don't even know what a spatula laser *is*.