More on tools

On Sun, 11 Apr 2021 09:03:27 -0500, AMuzi wrote:

On 4/10/2021 8:28 PM, Jeff Liebermann wrote:
" I wonder why they call both types of threads by the same name?"

'twist'
https://www.etymonline.com/search?q=thread

So, threading a needle means twisting the thread through the eye of
the needle? I can barely see the connection with "twist".

My guess(tm) is someone built a screw cutting lathe from a spinning
wheel in 1670 and called the process "threading" which morphed into
calling part of the result a "thread". It's possibly the same as
"bolt of fabric" morphed into the hardware "bolt" because they were
both made on similar rolling machines.

--
Jeff Liebermann
PO Box 272 http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS 831-336-2558

On 4/11/2021 1:27 PM, Jeff Liebermann wrote:
On Sun, 11 Apr 2021 09:03:27 -0500, AMuzi wrote:

On 4/10/2021 8:28 PM, Jeff Liebermann wrote:
" I wonder why they call both types of threads by the same name?"

'twist'
https://www.etymonline.com/search?q=thread

So, threading a needle means twisting the thread through the eye of
the needle? I can barely see the connection with "twist".

My guess(tm) is someone built a screw cutting lathe from a spinning
wheel in 1670 and called the process "threading" which morphed into
calling part of the result a "thread". It's possibly the same as
"bolt of fabric" morphed into the hardware "bolt" because they were
both made on similar rolling machines.



The root for 'twist' which became 'thread' refers to
_making_ a thread. (applicable to both cotton and steel
threads !)

I assume the verb form is 'installing a thread' much as one
'oars' to shore etc.

IIRC 'bolt' starts with crossbow ammo, extends to other
cylindrical things later.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On Sunday, April 11, 2021 at 2:04:37 PM UTC-7, AMuzi wrote:
On 4/11/2021 1:27 PM, Jeff Liebermann wrote:
On Sun, 11 Apr 2021 09:03:27 -0500, AMuzi wrote:

On 4/10/2021 8:28 PM, Jeff Liebermann wrote:
" I wonder why they call both types of threads by the same name?"

'twist'
https://www.etymonline.com/search?q=thread

So, threading a needle means twisting the thread through the eye of
the needle? I can barely see the connection with "twist".

My guess(tm) is someone built a screw cutting lathe from a spinning
wheel in 1670 and called the process "threading" which morphed into
calling part of the result a "thread". It's possibly the same as
"bolt of fabric" morphed into the hardware "bolt" because they were
both made on similar rolling machines.

The root for 'twist' which became 'thread' refers to
_making_ a thread. (applicable to both cotton and steel
threads !)

I assume the verb form is 'installing a thread' much as one
'oars' to shore etc.

IIRC 'bolt' starts with crossbow ammo, extends to other
cylindrical things later.
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971
I think that "bolt" didn't come from a cross bow arrow but the locking piece you slid across a door to prohibit entry. From there you can see the obvious connection of stopping a door to stopping a metal rod to a nut and bolt.

rOn Sun, 11 Apr 2021 11:27:41 -0700, Jeff Liebermann
wrote:

On Sun, 11 Apr 2021 09:03:27 -0500, AMuzi wrote:

On 4/10/2021 8:28 PM, Jeff Liebermann wrote:
" I wonder why they call both types of threads by the same name?"

'twist'
https://www.etymonline.com/search?q=thread

So, threading a needle means twisting the thread through the eye of
the needle? I can barely see the connection with "twist".

My guess(tm) is someone built a screw cutting lathe from a spinning
wheel in 1670 and called the process "threading" which morphed into
calling part of the result a "thread". It's possibly the same as
"bolt of fabric" morphed into the hardware "bolt" because they were
both made on similar rolling machines.

Nope, the first use of the word "bolt" or at least the words that
evolved into the modern English "bolt" was for a short heavy arrow. A
"bolt" of canvas dates from the 1400's as does it's use referring to a
short rod as in a door bolt.

As an aside I doubt that a 1670's spinning wheel could be converted to
a thread cutting lathe as it would have been made of wood :-)

--
Cheers,

John B.

On Sun, 11 Apr 2021 14:11:39 -0700 (PDT), Tom Kunich
wrote:

On Sunday, April 11, 2021 at 2:04:37 PM UTC-7, AMuzi wrote:
On 4/11/2021 1:27 PM, Jeff Liebermann wrote:
On Sun, 11 Apr 2021 09:03:27 -0500, AMuzi wrote:

On 4/10/2021 8:28 PM, Jeff Liebermann wrote:
" I wonder why they call both types of threads by the same name?"

'twist'
https://www.etymonline.com/search?q=thread

So, threading a needle means twisting the thread through the eye of
the needle? I can barely see the connection with "twist".

My guess(tm) is someone built a screw cutting lathe from a spinning
wheel in 1670 and called the process "threading" which morphed into
calling part of the result a "thread". It's possibly the same as
"bolt of fabric" morphed into the hardware "bolt" because they were
both made on similar rolling machines.

The root for 'twist' which became 'thread' refers to
_making_ a thread. (applicable to both cotton and steel
threads !)

I assume the verb form is 'installing a thread' much as one
'oars' to shore etc.

IIRC 'bolt' starts with crossbow ammo, extends to other
cylindrical things later.
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971
I think that "bolt" didn't come from a cross bow arrow but the locking piece you slid across a door to prohibit entry. From there you can see the obvious connection of stopping a door to stopping a metal rod to a nut and bolt.

Tommy boy, you really should learn to keep your mouth shut when you
don't know what you are talking about.

As Andrew says "bolt" or at least the words that evolved into the
modern English word "bolt" originally meant a short heavy arrow.
"Old English bolt "short, stout arrow with a heavy head;" also
"crossbow for throwing bolts," from Proto-Germanic *bultas (source
also of Old Norse bolti, Danish bolt, Dutch bout, German Bolzen),
perhaps originally "arrow, missile," and from PIE *bheld- "to knock,
strike" (source also of Lithuanian beldžiu "I knock," baldas "pole for
strikin:
--
Cheers,

John B.

On 4/11/2021 6:01 PM, John B. wrote:
rOn Sun, 11 Apr 2021 11:27:41 -0700, Jeff Liebermann
wrote:

On Sun, 11 Apr 2021 09:03:27 -0500, AMuzi wrote:

On 4/10/2021 8:28 PM, Jeff Liebermann wrote:
" I wonder why they call both types of threads by the same name?"

'twist'
https://www.etymonline.com/search?q=thread

So, threading a needle means twisting the thread through the eye of
the needle? I can barely see the connection with "twist".

My guess(tm) is someone built a screw cutting lathe from a spinning
wheel in 1670 and called the process "threading" which morphed into
calling part of the result a "thread". It's possibly the same as
"bolt of fabric" morphed into the hardware "bolt" because they were
both made on similar rolling machines.

Nope, the first use of the word "bolt" or at least the words that
evolved into the modern English "bolt" was for a short heavy arrow. A
"bolt" of canvas dates from the 1400's as does it's use referring to a
short rod as in a door bolt.

As an aside I doubt that a 1670's spinning wheel could be converted to
a thread cutting lathe as it would have been made of wood :-)


I happen to own a copy of 'Mechanics In 16th Century Italy'
so I know that carved wooden threads go back a very long
time (see Gutenberg's early-1400s press, for example).

and wine:
https://www.fastenerdata.co.uk/media...ne_press_1.jpg

But all that gets far afield.

The root of 'thread' in the sense of 'twist' describes
making thread.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On Mon, 12 Apr 2021 06:01:40 +0700, John B. scribed:


As an aside I doubt that a 1670's spinning wheel could be converted to a
thread cutting lathe as it would have been made of wood :-)

Only the cutting head needs needs to be able cut.
So how the rest of the machinery is not of initial concern.
Hint, flint headed arrows as the first example?.

On Sun, 11 Apr 2021 10:16:01 -0700, Tom Kunich scribed:

So can I. And I can recognize 3/8ths, 7/16's, 1/2", 9/16ths and 5/8ths
on sight. I don't see that as a talent but as trial and error taken to
an extreme.

Piffle, try giving dimensions to 1/1,000th of an inch.
Know some one who can eyeball that and his eyeball was backupfy
micrometer.

As to the sizes, bolt/nut sizes you list, those are just coarse common
sizes from the local,hardware shop.

On Sun, 11 Apr 2021 10:46:18 -0400, Frank Krygowski
wrote:

On 4/11/2021 10:01 AM, AMuzi wrote:
On 4/10/2021 6:01 PM, Frank Krygowski wrote:
On 4/10/2021 10:37 AM, Tom Kunich wrote:
On Saturday, April 10, 2021 at 7:21:46 AM UTC-7, Frank
Krygowski wrote:


Regarding https://www.lrfaq.org/Series/Other.threads.html
I've got a really handy chart hanging in my workshop. It
covers threaded
fasteners in Metric, U.S. and British systems, sorted by
diameter. To
identify a screw I measure the OD and scan down the
chart, then read to
the right to find the possibilities, including thread
pitches. It may be
the most frequently used chart in my work area.

Perhaps you can remind me since I've forgotten, but isn't
thread count counted in inches? i.e. A British BB thread
is 24 threads per inch but so is an Italian BB. Thinking
back the differences were in the threads with Italian
threads being triangular and British flattened on the top.

U.S. thread pitch is specified in threads per inch, or
"tpi." The most common screw size here is 1/4-20, meaning 20
threads per inch.

SI pitch is measured directly in millimeters. So a 5mm x 0.8
has 0.8 millimeters between adjacent thread peaks.

I doubt that Italian threads or any other normal fastener
threads are pointed on top. It's difficult to manufacture
threads that come to a complete point, unless you're turning
them on a lathe; they'd be easily damaged if you did make
them, and there's no need to do so. The tips of the sharp
threads would add negligible strength to the connection.


While you're right that standard commercial grade hardware is about 75%
engagement, teh Italian thread forms for bicycles are Whitworth
55-degree with rounded tops.

https://www.ring-plug-thread-gages.c...hread-Form.gif

So as I said, not pointed at the top.
Compare DIN metric:
https://www.ring-plug-thread-gages.c...data-1-28.html

I wonder about the practicality of the detail differences in thread
forms. If diameter and pitch were compatible, would there be a problem
screwing a nut with Whitworth form onto a U.S. or SI bolt? (Looks like
3/8"-16 or 1"-8 would be good for a U.S. to Whitworth test.)

I'm sure some details of the thread form get swallowed by tolerances, so
to speak. SI threads don't actually have geometrically perfect corners
between the various straight lines. Tooling wear and other
practicalities prevent that.

I could dig into my copy of Machinery's Handbook, I suppose... but it
seems like a question where wondering is more appropriate than detailed
research.

I've never tried it but I would think that screwing a Whitworth bolt,
say 1/4" - 20 TPI, into a ISO nut would be possible although I wonder
about the strength.

--
Cheers,

John B.