On 8/21/2019 6:54 PM, John B. Slocomb wrote:
On Wed, 21 Aug 2019 13:09:30 -0400, Frank Krygowski
wrote:

On 8/21/2019 12:19 PM, jbeattie wrote:

Having looked through the fasteners at my local Ace many, many times, I can guaranty you there there is no drawer, box or fastener labeled "Internal Wrenching Bolt." Maybe such a bolt exists, but what I use on my bike is labeled as a socket head cap screw. Go to Grainger: https://tinyurl.com/y4y89fww Type in "internal Wrenching Bolt" and see what comes up. Nada. An internal wrenching bolt is some odd-ball aircraft/military fastener with inch dimensions. It's not a metric fastener. Now go to the internet and type in "internal wrenching bolt" -- and get a bunch of military crap. https://military-fasteners.com/bolts...renching+bolts

The military has a long history of unusual names. For example:

================================================== =========

"'I understand,'' the Maine Republican said, ''that there is a story
coming out about a $600 toilet seat.''

''I think that gives new meaning to the word throne,'' Cohen added
before casually dropping the subject and moving on to weightier issues,
such as space defense and NATO burden sharing.

Within hours, the Defense Department publicists had cranked out a
statement challenging the senator`s characterization of the transaction.
Actually, the statement said, the Pentagon didn`t pay more than $600 for
a toilet seat.

''We believe the senator was referring to a lavatory cover which we have
recently learned has been priced at more than $600 by the contractor,
the Lockheed Corp.,'' the statement said.

According to Nick Duretta of Lockheed`s public information office, there
is a difference between a toilet seat and the lavatory cover purchased
for P-3 patrol planes that are now out of production.

''It (the lavatory cover) is more complex than a toilet seat,'' Duretta
said."

================================================== ========

That was pretty common knowledge in the sections that were in the
business of trying to keep experimental airplanes flying)

The story was that the A.F. had ordered a toilet "can"
cover for an experimental aircraft for which there was no spares in
the supply system, or manufacturer's stocks. What is the correct price
to set up and manufacture a cover, probably dimensioned in tenths of
thousands and made of some erotic material?

Hmm. I'd first do away with the "erotic" material. You don't want
flyboys getting hot, bothered and distracted.

Secondly, find a way to avoid tolerances as small as tenths. One reason
our students went through some machine shop fundamentals was so they
would realize how much work and expense is involved in "plus or minus
one thousandth," let alone one tenth.

But I once worked with a guy who had done design work for a company
producing military helicopters. (Sorry, I forget which.) He said that in
the engineering drawing room (back in the days of drafting boards) there
was a big display up on one wall, a selection of tools. The sign said
something like "They have to repair it with THESE."

The idea, supposedly, was to avoid exotic requirements in tools. One
would think the same idea should apply to toilet seats.

At the same time the F111B had some nose wheel landing gear bushings
that were called "fabroid bushings" that did not require lubrication.
They also failed very frequently, sometimes a frequently as every
flight and depending on the bushing they might cost $100 each and we
usually changed them as a full set so several hundred dollars per set.
And there were 3 experimental aircraft in the fleet. What to do?

That sounds like a terrible design flaw.

--
- Frank Krygowski