A Rant on Precision

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I had a cabinet to make last summer, and bought a special saw blade for plywood, as I have many times before. For the smoothest cut, the blade is hollow ground instead of having the teeth set, and there are 140 little teeth to avoid tearing the surface veneers. When I was done one small cabinet, the blade needed sharpening, rather soon, I thought, and then I saw that only the alternate teeth were dull, the others still being fresh. I got an exchange, and saw the trouble on the new blade - the files used to sharpen them were so dull that they were raising burrs, with higher ones on each "right hand" tooth. After marvelling at multi-faceted, diamond-honed Japanese saws, I was disappointed. I took the new one back, clearly labelled showing the .013" difference in the height of alternate teeth, and the store owner just said that his brand was high quality, and that nobody else had complained. What is wrong with people that they can't see what is wrong with a 140 tooth blade where only 70 teeth do all the work, and badly?
I got pretty excited, trying to get him to use a magnifying glass, if he needed it, to see the difference between his and a well-made sample, but he didn't "get it." I kept telling him I didn't care about my $15 - I was trying to save his brand, but he didn't seem to care.

From the consumer's point of view you are right, that product is not fit to be sold.

I wonder if a more precise saw would cost a lot more. That is a potential reason he might not want to admit the product's flaw. High priced items sell less easily.

The manufacturer may save pennies by not replacing the saw files, but they cost a lot more time or power to do their job. Or maybe they are using machining fluid, and the flow is blocked. One way or another, an inspector is not doing their job. Another store has a blade that could be from the same line for 2/3 the price, and only half as poorly made.

Some years ago, Ford dealers were having a hard time with inventory. Customers were avoiding the cars with US-made transmissions, in favour of the imported ones mixed in with the same products. Investigating, they found that they could tell the difference easily - the imported ones were quieter, and the customers had learned that they were also much more reliable. Tearing down some samples, the company found that the American ones were within tolerance, but the Japanese ones would still have been within tolerance if it was reduced 90%.

I volunteer as a bike mechanic at a place on the weekends. We do a little bit of everything, but primarily turn derelict junk bicycles into good working bicycles.
There is another guy who has been a regular volunteer for years who just insists on doing less than the bare minimum, often spends more time doing things the wrong way than it would have taken to do them the right way, regularly argues against doing whatever task is at hand properly, among other things.
It drives me crazy.
If I don't run into an unexpected problem, I can regrease a wheel hub in about twenty minutes. Maybe less. It's worth it. Someone is putting their life in my hands when they get on that bike, it needs to be done right.
Maybe not a rant about precision, but about quality workmanship.

Gad! At the best bike shop in Victoria BC, a mechanic told me that they didn't have the bolt I needed - theirs were too long. I suggested cutting one, and he protested that then the nut wouldn't go on. I demonstrated how to use his tools.
I was reading recently that Roy Moore was such a disruptive student that nothing would change his mind if he'd made a mistake. His prof had to give up classroom discussion when he was present.
There's a lot of Dunning-Kruger all over. One group of engineers I was in regularly gave equal time to a guy who kept proposing perpetual motion relationships.

When people are familiar with their tools, though...
I watched an Indian mechanic enlarge the diameter of a cylinder head stud with a hammer and a couple of gentle taps in order to cut new threads into a stripped engine case on the side of the road. Amazing.

But then I have an idea for a nearly perpetual motion device that I'm looking forward to attempting to build.
It's so simple.

Yeah, when I've used the same skill set for a couple of years, some pretty nice work happens.

There's a lot of "near" perpetual motion. I've got a notion for a way to upgrade heat energy directly, but I'd need nano-tools to try it. If you want to discuss yours, PM me. I vetted ideas for GE's Ecomagination contest.

Was this blade made in Japan? Or elsewhere? There are companies that import high quality tools that are made in Japan.

China. The local* stores have nothing better. I used to like the Vermont American flame-hardened ones.
* within a 5-hr drive.

My attempts to describe it accurately would probably fall short, and I haven't put together a good drawing yet. If/when I do come up with either of those or a prototype I'll let you know.
In a nutshell, two separate groups of halbach arrays arranged in a way that they cannot achieve a state of rest.

It's a bummer I'm not a mechanical genius----like you guys.

A friend has been working on magnetic perpetual motion periodically for years. I help him design easier test rigs. The last time he got really excited, he had worked out a path that showed a steady gain most of the way around. He spent a week or two in bliss before finally measuring the last few steps, where it all went away. However, he did it by just measuring forces and positions, without having to build moving frames.
I know Arcata mostly for Kinetic Sculptures. Still happening?

Still happens every year. I haven't been involved with it yet. I've wanted to but, social difficulties...
One of the guys I volunteer with at the bike library is the engineering judge for the race.
Have a loose plan for a sculpture, "the Roach Coach". One of these years.

Dyscalculia! And math that looks like alien writing! I can build just about anything, take it apart, fix it, understand it. But trying to do the math involved is way beyond me. So I'm more of a shade tree mad scientist.

Where I work, the cafeteria is called "The Roach Coach."

A great friend used to go for the mediocrity award, and a no-stall water exit. I love the rules like "Cheating is a privilege, not a right."
The only math I liked in school was geometry, but it turns out that the formulas for things like how far a 2 X 4" will bend turn out to be just a few keystrokes on a calculator. I took my notes in BASIC, and never had to think about the numbers again, just plug them in. I've always been pretty handy with rough estimates, but lousy at explaining my work. Quite a few people can do complex mental calculations correctly, but not explain how.
You know that famous disparity in math ability between boys and girls? When kids adopt an Avatar of the opposite gender, their math scores follow! Experience counts, too. If you built a car transmission "by the book" it would weigh over twice as much.