Black Diamond Neve Crampon


Aluminum crampons are great. I’d shied away from them after a friend advised, “When I really need crampons, I really want steel.” A couple of years later, my awesome girlfriend (who was tired of waiting for slowpants) got a pair for my birthday. They get the job done.

As important as climbing ability is their light weight. The Neves are 52% of the weight of my venerable cro-moly Sabreteeth; more than a pound lighter. The weight advantage makes them easy to bring along when the need for ‘pons is uncertain. I’ve used them on half the trips on which I’ve carried them; such was the summer in the Cascades.

The aluminum points stand up much better than expected to alpine rock. They wear and flex, but not quickly nor easily. While their forte is softer snow, when sharp they worked well on glazed autumn melt-freeze. They fit Mondo 30 ZZeros, Dynafit ONEs, and La Sportiva Trango S well, with room (!) for adjustment. The weights quoted here are, due to a little wear, slight underestimates of the weight when new. I’d guess I’ve worn 0.1-0.2 g of aluminum off each foot. There may be some dust in the straps, but not very much.

The weights/masses: 294.2 g for one, and 294.5 g for the other. Roughly 588.7±0.5 grams/pair.  The Black Diamond web page claims 576 grams/pair in December 2012. The pair weighed here was purchased in Autumn 2011; I can’t find a product page from 2011 for comparison. If the crampon/hardware is unchanged, then the product weight is 2% higher than advertised.

Binding Freedom Inserts


I headed up to ski today, but arrived at the gas station halfway there without a wallet. I had enough gas to get home, but not enough to ski, so it was off to the lab/shop for some ski work.

I’d played with a set of Binding Freedom inserts last season, remounting my very first pair of skis with inserts as rock skis. I’ve now drilled my Kailas and Sahales (whence the bindings came) for the inserts, and glue is curing in the Kailas. As I was cleaning up, I realized that my remaining stash of inserts would provide a nice example of how to  determine the uncertainty in product weight.

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Dynafit ONE PX TF 30.0


Christmas in November! When ZZero PX boots failed under warranty, Dynafit/Salewa sent a pair of the new Dynafit ONE PX as a replacement. Stoked.

Finish and mechanical quality is excellent. Boots are comfy and solid around the house. Palpably stiffer than the ZZero PX, but the walk mode is superior to the TLT4. I anticipate that these boots will ski well.

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Fun with Torque

\vec{\tau}=\vec{r}\times\vec{F}  ?

Nope, this kind of Torque – an excellent Android app that interfaces with the OBD II port in your car.

I’d bought an inexpensive “LM327” bluetooth adapter for my car months ago, but never got it running with my laptop. The Android solution worked trivially, and the application works well.

If you want to play with datalogging with Torque and you’re using the free version, you must explicitly select each sensor every time you use the application. Tedious, but free.

I finally went on a real drive with the car (~10-15 mi) and got logging working. There are many sensors to log, but most of them don’t betray fundamental properties of the car quite like these two do.

Lines are not fit. I tweaked the 5th gear line to match the 5th gear data, then used the gear ratios from here to predict the lower four lines. The ratios used were 3.545/2.111/1.448/1.088/0.780. Wikipedia has two values for the 5MT. The other ratio stated for “All 1990-2003 with EJ engine” of 3.785/1.945/1.500/0.994/0.780 is in obvious error when plotted with the same procedure. I submitted an edit to this effect; time will tell if it sticks.

Same plot, with incorrect ratios.

The GPS and my engine computer’s speedometer are neatly locked, but there’s about a 1 mph constant offset between them (easier to see in the residuals). Neat.