Some Blog Site

There are some things that everyone just knows, like tetanus is caused by rusty metal and planes can fly because of the Bernoulli principle. And of course everyone knows that the wisdom of crowds means that a bunch of people who agree on a topic must be right.

Not so fast though.

I learned something recently about the supposed wisdom of crowds. The book that started all this – by James Surowiecki – highlighted that phrase but the concept is a little more nuanced. Crowds are not wise because they are a large group of people, rather, crowds are wise because (or more correctly, if) the individuals bring unique information.

Consensus is useful if all parties have arrived at the conclusion independently, using their own methods and data sets. If everyone looks at the same data, you don’t have a wise crowd – you have a crowd of average intelligence.

I’m trying to figure out what’s a better situation for having a nail in a tire: hot weather or cold weather.

I have a slow leak in a tire and the leak rate seems to change with temperature.

One could argue that a hot tire is better because the softer rubber can better seal around the nail. One could also argue that a cold tire is better because the cold rubber will contract around the nail, providing a tighter seal.

I don’t know if there’s a nail in my tire, I just got thinking about the situation and haven’t decided yet. I’ll let you know if I ever resolve it.

In our Chrysler minivan (5th generation, model years 2008-2017), I had one of the rear brake calipers seize about a year ago. It turned out to be the lower slide pin that wouldn’t move.

In that design, the slide pin and boot are part of the fixed bracket, not the actual caliper. I couldn’t figure out a quick and easy way to fix it. Can’t replace a slide pin if it won’t slide.

At least they thought ahead and put a hex head on the end of the slide pin. So the pin wouldn’t slide back and forth, but I could put a wrench on it and wiggle it a little bit.

The rubber boot surrounds the slide pin and protects it from water/dust/dirt/salt/etc. In this case, it also prevented me from lubricating the pin so that it would move again. So I went against standard practice and cut a small slit in the boot. I then was able to stick the straw from the can of WD-40 inside the boot and put some WD-40 in there.

I then used the wrench to work the WD-40 throughout the slide pin and I could eventually move the pin fully again.

That was supposed to be a temporary measure. Mainly because I had the caliper off in order to replace the brake pads, and I couldn’t get the caliper back on with the pin stuck. Cutting a hole in the protective boot is not a good long-term measure. Lubricating the slide pin with WD-40 instead of brake grease is not a good long-term measure.

But that was several months ago and I actually forgot about it, probably because it has been working well.

Then this last weekend I noticed that particular brake that I fixed last year was noticeably cooler than the brake on the other side. I figured that meant it wasn’t working anymore, so I investigated. It turns out that it was working fine, it was the other side was running hot because its caliper was seized, causing the brake to drag all the time. Of course, it was the lower pin of the rear caliper, so it seems that’s a trouble spot for that caliper design.

At least I knew what to do this time – nick a spot in the boot, put some WD-40 in there, and work the pin loose with a wrench. It went rather well. We will see how long this side keeps working – the other side is still going strong.

I’ve noticed a disconnect between the standard practice of brushing one’s teeth before going to bed and the standard recommendation from dentists to brush one’s teeth after meals.

I never paid much attention to it, but I was trying to eat a little healthier and I became aware that I was tempted to snack in the evenings. What I found is that by brushing my teeth after dinner, rather than waiting until bedtime, provided enough of a mental barrier to prevent the temptation.

I know that I could have easily just brushed my teeth again later, but the psychology of “I already brushed my teeth” was good enough for me. Your mileage may vary.

A popular online debate is “what is the difference between torque and horsepower?”

I am here to answer that question. But I’m going to tie it to sports. And I’m just going to summarize it. So if you like discussing power in engineering units and if you appreciate football and if you like short blog posts, this is for you.

Simply put: horsepower wins games, torque wins championships.

That is all.

Beta thought he found a loophole. He started asking us questions, but he would quietly and quickly slip the word “not” in the question, so what we heard was the opposite of what he asked (in his mind). Stuff like “Do I (not) have to finish my dinner?”

Well, his brothers caught on and they found it equally amusing as he did. Pretty soon, I had 4 boys asking me a variety of inverted questions. Then they added the wrinkle of saying the “not” out loud, but saying many of them. “Dad, can I not not not not not not have dessert?” So I had to not only understand the question but count whether the number of nots was odd or even.

Around that point, Beta gave up. Shortly after, I gave up. I told the boys I would not answer any more yes/no questions because I couldn’t trust what they were asking.

Beta, though, helped me out: “Dad, just answer them with a full sentence.”

Oh.

That was simple.

“You do have finish your dinner.”
“You may not have dessert.”

Just because it’s phrased as a yes/no question does not obligate you to respond with only yes or no.

Unless you’re playing 20 Questions. (Which Gamma has changed to Unlimited Questions).

Here are some juice boxes that we bought. I think they are mislabeled.

They say they are juice boxes, made with fruit juice. But part of the package reveals otherwise.

That’s not a drink made from concentrated apple juice – it’s made from concentrated turkeys.