Today, one of our operators mentioned he was missing a special fastener. I asked him if
there was another one I could measure. Sure, he removed it using a 8mm hex key, I scaled
it and it looked like a 12mm long fastener with 6mm of it turned down to 6mm to keep a
sliding detail captive. No problemo!

Carbide has no problems with SHCS's but the head of the 12mm SHCS wasn't all that
cylindrical and didn't fit any of my collets. So I lightly held it by the threads, turned
head down to a diameter that fit a 9/16 collet and proceeded to make my fastener.

Didn't fit. Okay, must have mushed the leading edge of the threads. So I grind on a
lead. Still doesn't fit. Maybe I distorted things a bit, I used a lathe to turn it down,
maybe tool pressure the bent the leading edge of the thread over. Ran a thread file
across it, screwed it into a 12mm nut and it fits. Still doesn't fit the machine.

So I start to get a clue, go back to my tool box, grab a 5/16 hex key and notice that that
fits a 12 mm shcs fine. I proceeded to learn that a 1/2-13 screw will screw into a 12 mm
nut just fine but a 12mm screw will not screw into a 1/2-13 nut. Argh!

It was Monday.

Wes

"Wes" wrote in message
...
Today, one of our operators mentioned he was missing a special fastener.
I asked him if
there was another one I could measure. Sure, he removed it using a 8mm
hex key, I scaled
it and it looked like a 12mm long fastener with 6mm of it turned down to
6mm to keep a
sliding detail captive. No problemo!

Carbide has no problems with SHCS's but the head of the 12mm SHCS wasn't
all that
cylindrical and didn't fit any of my collets. So I lightly held it by the
threads, turned
head down to a diameter that fit a 9/16 collet and proceeded to make my
fastener.

Didn't fit. Okay, must have mushed the leading edge of the threads. So I
grind on a
lead. Still doesn't fit. Maybe I distorted things a bit, I used a lathe
to turn it down,
maybe tool pressure the bent the leading edge of the thread over. Ran a
thread file
across it, screwed it into a 12mm nut and it fits. Still doesn't fit the
machine.

So I start to get a clue, go back to my tool box, grab a 5/16 hex key and
notice that that
fits a 12 mm shcs fine. I proceeded to learn that a 1/2-13 screw will
screw into a 12 mm
nut just fine but a 12mm screw will not screw into a 1/2-13 nut. Argh!

It was Monday.

LOL
That's one for the books Wes.

JC

"John R. Carroll" wrote:

LOL
That's one for the books Wes.

Stacked groovers and 10-32 screws is another issue I've run into . There is a metric
screw that *almost* works. Tightens up just before that stack tightens. At least it
isn't me do it.

Wes

"Wes" wrote in message
...
"John R. Carroll" wrote:

LOL
That's one for the books Wes.

Stacked groovers and 10-32 screws is another issue I've run into . There
is a metric
screw that *almost* works. Tightens up just before that stack tightens.
At least it
isn't me do it.

Opsie!

Ever had to get the FAA to PMA one of your replacement parts?
It takes quite a while. I'm doing one now that's gone on long enough that
...... well, here is the email.

"Folks,
With the passing of XXXX XXXX, do you want me to set up another Flam DER
that I have worked with?
I will also inform XXXX on who the person will be so that she can change her
paper work.
Best Regards
XXXX
Note: I will be out of the country the latter part of this week and
returning on Sunday."

I got everyone together on a conference call and suggested we get a move on
before anyone else expired.

--
JC

In article , wrote:
Today, one of our operators mentioned he was missing a special fastener. I asked him if
there was another one I could measure. Sure, he removed it using a 8mm hex key
[...]
So I start to get a clue, go back to my tool box, grab a 5/16 hex key and notice that that
fits a 12 mm shcs fine.

FWIW, 8mm and 5/16" are close enough to the same that wrenches are
interchangeable for most purposes; likewise 16mm and 5/8".

Yeah there ARE those things that get ya...

I do a LOT of 1/8 scale model work (some of you know I build steam
locomotives).

In the smaller locomotives there are a bunch of 5-40 bolts... 5-40 shaft
size/clearence is 1/8 inch, which is why it's used a lot, scales out to 1
inch.... UMMMM, NEVER, EVER, EVER... get your 4-40 and 5-40 hardware
mixed....

4-40 goes in a 5-40 threaded hole or bolt just fine... till you try and
tighten it...:-)

--.- Dave


"Wes" wrote in message
...
Today, one of our operators mentioned he was missing a special fastener.
I asked him if
there was another one I could measure. Sure, he removed it using a 8mm
hex key, I scaled
it and it looked like a 12mm long fastener with 6mm of it turned down to
6mm to keep a
sliding detail captive. No problemo!

Carbide has no problems with SHCS's but the head of the 12mm SHCS wasn't
all that
cylindrical and didn't fit any of my collets. So I lightly held it by the
threads, turned
head down to a diameter that fit a 9/16 collet and proceeded to make my
fastener.

Didn't fit. Okay, must have mushed the leading edge of the threads. So I
grind on a
lead. Still doesn't fit. Maybe I distorted things a bit, I used a lathe
to turn it down,
maybe tool pressure the bent the leading edge of the thread over. Ran a
thread file
across it, screwed it into a 12mm nut and it fits. Still doesn't fit the
machine.

So I start to get a clue, go back to my tool box, grab a 5/16 hex key and
notice that that
fits a 12 mm shcs fine. I proceeded to learn that a 1/2-13 screw will
screw into a 12 mm
nut just fine but a 12mm screw will not screw into a 1/2-13 nut. Argh!

It was Monday.

Wes

Doug Miller wrote:
In article , wrote:
Today, one of our operators mentioned he was missing a special fastener. I asked him if
there was another one I could measure. Sure, he removed it using a 8mm hex key
[...]
So I start to get a clue, go back to my tool box, grab a 5/16 hex key and notice that that
fits a 12 mm shcs fine.

FWIW, 8mm and 5/16" are close enough to the same that wrenches are
interchangeable for most purposes; likewise 16mm and 5/8".

Also 4mm and 5/32", 11mm and 7/16", 19mm and 3/4".

David

Wes writes:

I proceeded to learn that a 1/2-13 screw will screw into a 12 mm
nut just fine but a 12mm screw will not screw into a 1/2-13 nut.

Shouldn't that be the other way 'round? Half inch is bigger than 12mm.

Richard J Kinch wrote:

Wes writes:

I proceeded to learn that a 1/2-13 screw will screw into a 12 mm
nut just fine but a 12mm screw will not screw into a 1/2-13 nut.

Shouldn't that be the other way 'round? Half inch is bigger than 12mm.


Arrgh! It was a M10x1.5 Good catch.

Wes
--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller

On Mon, 27 Apr 2009 18:35:37 -0400, Wes wrote:


So I start to get a clue, go back to my tool box, grab a 5/16 hex key and notice that that
fits a 12 mm shcs fine. I proceeded to learn that a 1/2-13 screw will screw into a 12 mm
nut just fine but a 12mm screw will not screw into a 1/2-13 nut. Argh!

It was Monday.

Wes


To add insult to injury, I have a proportion of my collection of BSW, BSF and
UNF SHCSs that _really do_ have metric heads. This wasn't unheard of with
European agricultural machinery manufacturers a few years back. Doesn't cause
too much of a problem, if the imperial Allen keys don't quite fit, the metric
ones get tried just in case.


Mark Rand
RTFM

Richard J Kinch wrote:

Wes writes:

I proceeded to learn that a 1/2-13 screw will screw into a 12 mm
nut just fine but a 12mm screw will not screw into a 1/2-13 nut.

Shouldn't that be the other way 'round? Half inch is bigger than 12mm.


I finally had time to back trace it. I'm working on metric tooling and 10mm and 3/8 must
have been what I was having a bad day with.

Wes