Archive for category Science
The side of our house seems to attract Organ Pipe Mud Dauber Wasps during nesting season.
One pair of wasps built this impressive structure behind the patio door, beside the bathroom window:
The female wasp built six tubes over the course of an August week, carrying blobs of mud the size of her head and abdomen from sources about 30 seconds away (1 minute round trip). Each blob produces half of one serration around the tube, with a seam running down the middle, and requires 20 seconds to smooth into place. We got tired just watching her!
Each tube has many compartments, each containing a wasp larva and a paralyzed spider, with a mud cap inside the end:
We watched the wasps attack, sting, and remove spiders of a specific size from the corners of our window frames.
The young wasps in the innermost tube may not make it out alive, because they must chew through at least one outer tube before flying away:
Perhaps layering the outer tubes around a central tube makes for a more compact and durable nest, with the possible sacrifice of offspring in the center.
The new wasps will likely emerge next spring.
This year, we’ve seen more, if not many, Monarchs in flight. They’re not abundant, but perhaps there’s hope.
A Monarch evidently laid eggs in our milkweed patch, with at least two offspring surviving:
We decided to let them seek their own destiny; may the odds be ever in their favor …
So it’s not unusual to ride under a small plane on final approach. Having a Gulfstream V fly directly overhead, however, is a real attention-getter:
What’s not at all obvious from the picture is how big a GV looks when seen directly overhead through those trees just ahead on the corner where our paths crossed. There’s a 360 ft (above sea level) hill directly on the flight path, so it’s at maybe 600 ft ASL and 400-ish ft AGL.
Thrust-reversal thunder rolled over us 50 seconds later, as we rode up the rail trail access ramp. Figuring we’re 15 sound-seconds from the strip, the GV was 30 seconds from touchdown.
Not much to my surprise, my hack-job thermistor rebuild went bad:
Having nothing to lose, I heated the brass tube over a butane flame to wreck the epoxy, which blew out with a satisfactory bang and filled the Basement Laboratory with The Big Stink.
Much to my surprise, the active ingredient still worked:
The multimeter reported absolutely no intermittent dropouts for as long as I was willing to watch the trace while doing other things:
So it must be my crappy soldering technique.
A brace of real M2 thermistors will arrive shortly …
We’re waiting at the end of Burnett Blvd, with the signal red and the clock at T = -0.17 seconds (photo numbers in 1/60 second frames):
You can’t hear the car (barely visible) approaching on the far left, but we can.
T = 0.00 – We get a green light and the (more visible) car is accelerating hard:
T = 1.00 – The car reaches the crosswalk:
Note that the driver of the car to our right isn’t moving, either.
T = 2.03 – Car passes through intersection:
The view from above, showing the distance between those two positions is 100 feet:
Do the math: 100 ft / 1.03 s = 97 ft/s = 66 mph.
There’s a reason we don’t start moving instantly when a traffic signal turns green.
T = 3.17 – We start moving, as does the car to our right, with our signal still green:
T = 4.88 – Whoops, our signal turns yellow:
T = 9.28 – Our signal turns red:
The signal timing hasn’t changed over the years:
- Green = 4.88 s
- Yellow = 4.40 s
Elapsed time from green to red: 9.28 seconds. No problem if you’re a car, death if you’re a bike.
T = 10.42 – We’re pedaling hard in the intersection:
The white car to our far right started moving into the intersection about the time we did. If you’re going to say we shouldn’t run the light, you gotta deal with cars first, OK?
Note the car approaching from the right on the far side of Rt 55. That’s a 40 mph zone, the driver sees a green light, and we’re still in the intersection.
T = 12.50 – We’ve been moving for 9.33 s, which puts Mary directly in the path of the oncoming car:
T = 14.83 – The oncoming driver having spotted us and slowed down, we’re asymptotically approaching the right-hand lane of Rt 55, passing beyond the steel manhole cover:
If you plunk “burnett signal” into the search box at the upper right, you’ll find plenty of previous incidents along these lines.
Despite bringing this hazard to their attention many times (“We appreciate and share your interest in making our highway systems safe and functional for all users.“), NYS DOT obviously doesn’t care.
If any of their employees commuted to their office building (which overlooks this very intersection), perhaps they would care, but they don’t: we have yet to see a bicycle in the DOT’s token bike rack.
DOT says they’re in favor of Complete Streets, but, seven years on, it’s just another day on the only route between Arlington and the Overocker Trailhead of the Dutchess County Rail Trail.
Obviously, the good folks at Park Tool never anticipated a three-cross spoke pattern on a 20 inch wheel:
It’s my trusty Park Tool TM-1 Spoke Tension Meter, unchanged since shortly after the turn of the millennium.
For future reference, the rebuilt wheel spoke tensions came out around 25, slightly lower than the 27-ish I measured on Mary’s bike; it didn’t occur to me to measure the tension until after I’d relaxed the spokes. I’ll ride it for a while before doing any tweakage.
The spoke pattern is pretty close to four-cross, due to the large-flange Phil Wood hubs:
Which makes for a hella-strong wheel, particularly seeing as how it’s very lightly loaded. The Tour Easy we got for our lass came with a radially spoked rim around a Phil hub.
I transferred the hub and laced spokes intact to the new rim by the simple expedient of duct-taping the spokes into platters, removing the nipples, stacking the rims, sliding the spokes across into their new homes, reinstalling the nipples, then tightening as usual.
Ten months ago, I cleaned the corrosion off our favorite cheese slicer:
After cleaning, I coated it with XTC-3D epoxy:
We’ve been using it daily ever since and it spends most of its life drip-drying in the dish drainer. I added a third opening to the cheerful orange measuring spoon holder just for the slicer.
A few weeks ago I noticed corrosion once again growing on the handle:
I think the rot comes from water diffusing through the epoxy, rather than gross leaks through damage or pinholes. The tip of the handle has the most corrosion, probably due to the water drop hanging there, even though it also has the thickest epoxy coating: it cured with the handle pointing downward.
Verily, rust never sleeps …