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How does that work?
  • Power can be computed as torque times angular speed, which requires measuring the torque. (Speed is easy.)
  • Or it can be computed as the time derivative of ½mv², which requires knowing the mass. (Again, speed is easy, for known wheel diameter.)

As I understand it, it is essentially a strange gauge coupled with a cadence sensor. It is essentially measuring the power that the rider is putting into the pedals. The strain gauge part of this variety replaces the standard spider of the crank set, which is the part that ties the cranks to the chain rings. Reports out as Wattage and Cadence via bluetooth/Ant+ which my head unit receives and displays as either live, 3 sec average or 10 sec average. Quick testing on the trainer looks like 3 sec average will probably be the way to go. Supposedly accurate to +/- 2%.

There are also versions where the power is measured on the pedal itself, and at the crank arm. All have their advantages and disadvantages. Since I knew I could do the swap myself, the spider version made the best cost-performance sense for me.
 
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How does that work?
  • Power can be computed as torque times angular speed, which requires measuring the torque. (Speed is easy.)
  • Or it can be computed as the time derivative of ½mv², which requires knowing the mass. (Again, speed is easy, for known wheel diameter.)
I think some of the earlier ones measured the cadence and the tension on the chain was inferred by the resonance frequency. Many ways to skin a cat.
 
Well I got a new bike. It's the human-powered kind, but a good one. How good? Let's put it this way, it's got hydraulic brakes. An entry-level "gravel bike". Can't wait to try it out. It'll be ready for me in a week or so. Might as well progress in the sport as much as I can, while I still can and before my own parts begin to wear out. 🚴‍♂️
 
Well that was exciting. Melbourne Australia just got hit by an earthquake! 5.8 magnitude apparently, about 10km down. Epicenter was about 150km north of here. Everything started shaking around quite a bit, including some large spectrometers near me. You could actually see the building flexing.

A rocket fell of my shelf (and the Concorde pencil sharpener) but luckily the LEGO ones stayed put :).
20210922_091723.jpg
 
Well that was exciting. Melbourne Australia just got hit by an earthquake! 5.8 magnitude apparently, about 10km down. Epicenter was about 150km north of here. Everything started shaking around quite a bit, including some large spectrometers near me. You could actually see the building flexing.

A rocket fell of my shelf (and the Concorde pencil sharpener) but luckily the LEGO ones stayed put :).
View attachment 482921

Nice looking Nike Apache. What scale?
 
Hydraulic discs are so good. Love them. The wet doesn't seem to cause them many problems like rim brakes.
I just put Kool Stop pads on my Cross Check with canti brakes. I had to replace them due to normal wear, but their pad compound is big step up from most rim brakes.. I ordered that frame and had it built before disc brakes were common on Cyclocross bikes. I have hydraulic disc brakes on my mountain bike and I love the effortless stopping power and how easy it is to regulate your speed with one finger on the brake lever.

For the non-cyclists here, be careful if you ever ride a bike with good disc brakes. The first time you grab a fistful of the front brake lever, you'll probably be flying superman style over the bars. (Or at least so I've heard :rolleyes:)
 
I just put Kool Stop pads on my Cross Check with canti brakes. I had to replace them due to normal wear, but their pad compound is big step up from most rim brakes.. I ordered that frame and had it built before disc brakes were common on Cyclocross bikes. I have hydraulic disc brakes on my mountain bike and I love the effortless stopping power and how easy it is to regulate your speed with one finger on the brake lever.

For the non-cyclists here, be careful if you ever ride a bike with good disc brakes. The first time you grab a fistful of the front brake lever, you'll probably be flying superman style over the bars. (Or at least so I've heard :rolleyes:)

You'll have to pry my XT quad piston stoppers from my cold dead hands. Never getting rid of them. 😃
 
Oh man, I have brake envy now. The biggest problem I’ve had with my bike is the front rim brakes. The Axis 1.0 rim brakes that came standard are a pain, had a fight with the front not completely releasing on my last ride. Nothing some lube couldn’t fix, but I didn’t have that 20 miles from home. I see some Shimano 105s in my future. Bikes were so limited when I bought mine I wasn’t able to find one with disk brakes for under about 5k…I only found 3 bikes locally that were my size under about 4k.
 
Oh man, I have brake envy now. The biggest problem I’ve had with my bike is the front rim brakes. The Axis 1.0 rim brakes that came standard are a pain, had a fight with the front not completely releasing on my last ride. Nothing some lube couldn’t fix, but I didn’t have that 20 miles from home. I see some Shimano 105s in my future. Bikes were so limited when I bought mine I wasn’t able to find one with disk brakes for under about 5k…I only found 3 bikes locally that were my size under about 4k.

105s will be just fine. I have Sram Rival on my road bike and even in some really sketchy road races, those rim brakes work really well.
 
If you do go for discs do a bit of research and make sure you don't get ones that are prone to squeal. Some of the earlier ones were atrocious.

So true. Avid BB7s...ugh. Especially in winter/snow. FWIW, TRP Spyke and Spyre cable-actuated discs have been silent for our fat bikes and cross bikes in any conditions. Shimanos have also been silent, and I really like Shimano hydros with TRP rotors. A bit meatier rotor and no noise.
 
If you do go for discs do a bit of research and make sure you don't get ones that are prone to squeal. Some of the earlier ones were atrocious.

105s will be just fine. I have Sram Rival on my road bike and even in some really sketchy road races, those rim brakes work really well.

Would probably cost as much to convert to disk as my bike cost originally (man wheels are expensive), so I think I’m along for the ride as it were. The Axis stop me fine, but the partial sticking, and a few other minor misbehaviors have me thinking swapping for 105s is a pretty easy way out. I’m not much on riding in the wet, so rim brakes are fine for me.
 
Ah coin was just there for scale... ;)

The area used to be underwater (millions of years ago) and is pretty famous for fossil hunting (1st time we went). Things in picture are fossil oyster shell, right top are a few concretions (interesting mineral formations), fossilized shark teeth (two different types of extinct sharks - possibly porbeagle and crow sharks), and bottom two are fossilized worm holes or some type of burrow (basically stuff fills the hole and becomes a fossil). Apparently you can find arrow heads and other artifacts here but we did not. Found a bunch of other stuff that turns out to be rocks (really thought some might be fossils) and a couple of bones of modern animals. Still learning and hope to go back. My wife was the least enthusiastic and turned out to be the best at finding sharks teeth and had lots of fun.

https://written-in-stone-seen-throu...15/01/big-brook-new-jerseys-classic-late.htmlhttp://www.njfossils.net/cover.htmlhttps://www.fossilguy.com/sites/bbrook/index.htm

I went to visit a local vendor years ago and it turns out the guy was both a big game hunter and a fossil collector. His main conference room was full of giant creatures (bear, elk, moose etc.) that he hunted - very intimidating and smelled musty a bit. . . That's not my thing, but I didn't complain.

At some point, I mentioned a trip to the Florida Keys and how it was neat to see fossils in the coral and he stopped the meeting and took me to his office, where he showed me a ton of fossils collected over his lifetime. He had a lot of Megaladon teeth and said he had collected the most full collection of defective teeth and categorized them and it was now on display at a museum (not sure which one, but it sounded impressive).

I can't vouch for his collection or even know if it was made up of Megaladon teeth or not, but they were huge and there is no question that the stuff in the main conference room were real animals, so I assume he wasn't making stuff up.

I wish I had a smartphone back then, as I would have taken pictures of the fossils. I'd say there were 50-ish 2ftx2ft wood/glass presentation boxes, stored in racks by his desk and computer. It was a big office. The conference room was huge and full. . .

Sandy.
 
I installed a 30,000 btu heater in my shop outbuilding. This could also be considered rocketry related as the building is the Workshop of the Rocket Ships. God knows posting such a mundane occurrence is torturous enough to the reader, even if you only post it once. The old heater is visible behind the new one. It is still in the shop as it weighs about 250-300 lbs. When I bought the property last year, the Fire Department had shut off the gas to the building due to the old heater. It was of such an age that it did not incorporate a thermocouple or control valve. If the fire goes out, the gas keeps on rolling. An early effort at a moon rocket, too flippin' heavy to fly though. Really good at explode and burn though. I picked the new heater up for $200 on ebay. That's a real good price and the heater works well on testing. I did have a bit of a time getting it to light initially. The gas line had been shut down long enough that the gas in the line had reacted out. I had to flush it surprisingly hard to get a combustible mix delivered to the heater.
shop heater 003.JPG
Jim
 
A message from my mentor and spiritual advisor:

“Recent interpretations on my attire has made me very, very angry! My belt of armor is not artistic in nature. It is a cingulum militare with hanging baltea, as worm by Roman legionaires and divinity. I can not help it if Martian gravity is insufficient to keep each balteus in a protective vertical position and therefore I will be experimenting with elasticity to rectify their orientation. That is all, Earthlings.”

IMG_2380.jpeg

https://www.romanobritain.org/8-military/mil_roman_soldier_belt.php
 
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What are the notes taped to the tiles for? And what are the cups for?

The notes. We pulled the tiles out of the boxes and separated them into similar looking groups. There were 60 (+/-) tiles in total, and something like 30 different patterns. Each pattern got a number. Putting post it notes on them with their unique number assured we didn't have identical tiles in close proximity to each other.

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The cups. We used Ridgid Level Max anti lippage system. Basically stems and screw on retainers that help to ensure the tiles are level. Placing the cups over the stems ensures you see them and don't trip over them when walking down the hall.

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Went to a baseball game, Las Vegas Aviators vs Oklahoma City Dodgers
 

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I finally had a few hours without rain, clouds, and the moon last week to test the telescope. The auto-guiding mount still takes me a while to set up, but it is really cool.

I saw the rings of Saturn, the moons of Jupiter, and the "stripes" of Jupiter from my driveway. With an upgraded eyepiece, I have no doubt that I'll be able to see the Cassini Division and the Red Spot. No photos yet--that's coming (after I spend more money!)--but I'm really impressed thus far.
Here’s a couple decent pics I got with my IPhone
 

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