On 8/21/2019 6:50 PM, Tom Kunich wrote:
On Wednesday, August 21, 2019 at 11:22:40 AM UTC-7, Frank Krygowski wrote:
On 8/21/2019 1:46 PM, Tom Kunich wrote:
On Wednesday, August 21, 2019 at 10:04:50 AM UTC-7, Frank Krygowski wrote:
On 8/21/2019 11:39 AM, Tom Kunich wrote:
On Tuesday, August 20, 2019 at 7:05:22 PM UTC-7, Chalo wrote:
Tom Kunich wrote:

By the way - It is NOT a "cap screw". It is as I said, and Internal
Wrenching Bolt. Now they are often mislabeled and you'd find a Cap
Screw in the wrong bin.

I had to look up your laughable term to see if anybody else had heard of it. It turns out that an "internal wrenching bolt" is a Jim Crow-era NAS (US aviation industry) designation for a certain kind of cadmium-plated fastener which is by definition not metric. While the decorative head on a craptastic linear-pull brake cable fixing screw is superficially kind of similar, it's not an inch-sized, cadmium-plated, ludicrously expensive airplane part. So it's not what you say it is.

But feel free to keep doubling down.

You are perfectly welcome to invent any name you like for a common head shape. You can even tell everyone that because some have metric hex interiors instead of English size hex that it is a completely different head shape. Is there something wrong in your head for which you simply cannot agree on a commonly available part?

Tom, the point is: many of us are very familiar with bike hardware. Only
one of us seems to think we should call that thing an "internally
wrenching bolt." That's true whether or not you can find it on a page
devoted to aircraft hardware. Using that moniker is a failure to
communicate.

This reminds me of another tempest-in-a-teapot in the bicycling world.
Back in the 1980s, perhaps, some manufacturers organization tried to
change the words used for different types of bike tires. IIRC, they were
happy enough with "tubulars" but they said almost all "clinchers" didn't
really meet _their_ official definition of what a "clincher" tire was.

So they said the name "tubular" could remain, but the proper name for
what we call "clincher" was ... wait for it! ... "TIRE"!

We all know how well that effort worked out.

--
- Frank Krygowski

Frank, as a past teacher I am very surprised that you think you could call it "one of those things" or a "cap screw" which is a completely different shaped head. As a supposed mechanical engineer I am also surprised that you wouldn't know WHY that head has the specific shape. You continually surprise me with the mechanical engineering education of a 1st grader. Excuse me but if you don't think that things should be called by their correct designation you are pretty silly. You can join Chalo who thinks that it is a "Jim Crow Era" designation of an English threaded component.

Here are the relevant questions:

Have you tried walking into a bike shop and asking for an "Internally
Wrenched Bolt" in the appropriate size (which is probably 5mm x 0.8, or
maybe 6mm x 1.0)?

Have you tried that at a hardware store?

If so, what were the responses?

If not, why don't you try those and report back?

I maintain that it's silly to insist on an "official name" that is
almost universally unrecognized.

--
- Frank Krygowski

I asked you a question:

I think you should go first. Why didn't you answer the above?

As a teacher did you recommend to your students to put any name they felt like on a component?

One thing I taught was not to obfuscate using weird jargon. Correct
names for parts? Certainly. Obscure names used in communication with
non-specialists? Not a good idea, unless one first defines the terms.
And I did counsel them to define obscure terms.

Now, if you went into a bike shop and said "This stripped bolt is called
an Internal Wrenching Bolt. Can I buy one?" I'm sure they would say "Um,
yes sir, we've got those." But when you left, they'd be laughing about
"internal wrenching."

Second - are you even AWARE that the design of that head was very specific for a purpose?

I'm aware of a larger than normal radius between the body and the head,
to reduce stress concentration in tension. But that doesn't seem to be
what you're imagining.

So what, precisely, _are_ you imagining? You haven't explained it
sufficiently. (And if, on a test, you gave me the vague answer you gave
here previously, you'd lose points.)

--
- Frank Krygowski