Question about bearing cones.

On Tuesday, October 29, 2019 at 4:33:28 AM UTC-4, Dan S. MacAbre wrote:
Steve Weeks wrote:
On Monday, October 28, 2019 at 6:11:28 AM UTC-5, Dan S. MacAbre wrote:
The cones in the front wheel bearings are very pitted and creaky,
and I'd like to get some replacements... I can't find much on the web regarding this...

I've had good luck finding replacements he https://wheelsmfg.com/products/hub-parts/all-cones.html

Steve


Thanks! I'm sure I can find something there. I'll see if they ship to
the UK :-)

BTW, when they talk of the 'diameter' (8, 9, 9.5, 10mm) is that the
diameter of the axle /before/ tapping (i.e. the bare bar), or is it the
overall diameter of the threaded bits (which generally look a bit larger
to me), or the 'bottoms' of the thread grooves? Does (for example) 8mm
translate directly to the M8 metric thread size?

Thread sizes refer to the outside (or major) diameter of the male threads... but
see below.

Yes, threads are often larger than the rod or tube in its unthreaded condition.
That happens when the threads are rolled (pressed) into the metal, which is the
best way. Threads that are cut should be about the same diameter as the uncut
rod.

Except that threads tend to be just a little under their nominal size. That's
because the extreme tips of threads are difficult to make to a razor-sharp point,
and they don't help the strength of the thread anyway. So they may be formed to
have (say) 75% of the theoretical thread profile, omitting the 25% at the point.
That makes a nominal 8mm thread slightly less than true 8mm. How much less? It
varies.

In my workshop, I've hung a little chart that covers metric, U.S. and Whitworth
threads, ranked by major diameters. To identify a thread, I measure its major
diameter using calipers, then see which sizes it might be. I confirm by
measuring the thread pitch (that is, the number of threads per inch, or
millimeters per thread).

- Frank Krygowski

AMuzi wrote:
On 10/29/2019 3:37 AM, Dan S. MacAbre wrote:
jbeattie wrote:
On Monday, October 28, 2019 at 12:13:05 PM UTC-7, Steve
Weeks wrote:
On Monday, October 28, 2019 at 6:11:28 AM UTC-5, Dan S.
MacAbre wrote:
The cones in the front wheel bearings are very pitted
and creaky,
and I'd like to get some replacements...* I can't find
much on the web regarding this...

I've had good luck finding replacements he
https://wheelsmfg.com/products/hub-parts/all-cones.html

Steve

Most decent shops have that exact box of cones.* BTW,
Ofmega stuff was an O.K. Campy knock-off, and they made
all the Avocet stuff, some components better than others.
I broke an Ofmega track crank arm.

-- Jay Beattie.


The Ofmega bits seems nicely made.* I'd guess it was a
good-quality bike, and would like to keep it going as long
as is practical.* The most annoying thing is trying to keep
the side caliper brakes central. :-)

Yes, Ofmega components are generally well made.

Clean the caliper and oil your fasteners. Adjust such that arms move
freely without end play. Lock adjustment.Secure caliper to frame. Ensure
wheel is centered in fork or between stays.
Turn the centerbolt[1] until pads clear equally on both sides.

The arms float on the spring which is in the centerbolt slot.

Directions and diagram:
http://www.yellowjersey.org/photosfr...t/WEINTECH.JPG

[1] Better quality calipers have a wrench slot on the centerbolt. Others
may be turned with two wrenches, one on the mounting bolt and one on the
locknut or adjusting nut.


Okay, thanks. It's be nice to get this sorted once and for all, or at
least to find a reliable technique. The part of the caliper that is
bolted to the frame seems to be made to be held still with a thin
spanner (the sort of thing that comes supplied), but it's not easy for
me to get anything that fits exactly into that position. If I practise
enough, though, I'm sure I'll get there in the end.

AMuzi wrote:
On 10/29/2019 3:33 AM, Dan S. MacAbre wrote:
Steve Weeks wrote:
On Monday, October 28, 2019 at 6:11:28 AM UTC-5, Dan S.
MacAbre wrote:
The cones in the front wheel bearings are very pitted and
creaky,
and I'd like to get some replacements...* I can't find
much on the web regarding this...

I've had good luck finding replacements he
https://wheelsmfg.com/products/hub-parts/all-cones.html

Steve


Thanks!* I'm sure I can find something there.* I'll see if
they ship to the UK :-)

BTW, when they talk of the 'diameter' (8, 9, 9.5, 10mm) is
that the diameter of the axle /before/ tapping (i.e. the
bare bar), or is it the overall diameter of the threaded
bits (which generally look a bit larger to me), or the
'bottoms' of the thread grooves?* Does (for example) 8mm
translate directly to the M8 metric thread size?

It's the outer diameter of the thread, less thread tolerance[1].
Standard bolt-on fronts are m8x1.0, QR fronts are m9x1.0 and so on.
Typical:

https://i394.photobucket.com/albums/.../DIN912_M6.jpg


Cheaper fat tire style bikes use 'heavy duty' fronts with m9.5x1.0 and
m10x1.0 of generally lower quality.

Going back to earlier times (older than your bike), a host of variables
ensue such as French metric m9x0.9, Campagnolo 9f26, Raleigh 1/4-26W
(measures 7.8mm) and mo

https://www.practicalmachinist.com/v...-standards.jpg


[1] Standard hardware runs well below 100% thread engagement so the
actual measurement across the thread peaks will be less than the nominal
size. see also:
http://www.yellowjersey.org/photosfr...t/FWTHREAD.JPG

and
https://www.engineersedge.com/thread...engagement.htm


Thanks again. I don't know whether it's because I live in the UK, but
most of the axle descriptions I see are in Imperial sizes (i.e. 5/16"
and 3/8"). I know there is backward compatibility to consider, and that
(of necessity) most of these things will be the nearest approximate
equivalents; but I guess that the actual thread pitch is the most
important factor. So, do all bike components have metric threads now?
it may seem a silly question, but I have worked with computer
specialists from the US that have no idea what (for example) a 10mm page
margin looks like, and I feel that there is some resistance over there.
I quite understand that, of course - there is still some resistance over
here :-)

Frank Krygowski wrote:
On Tuesday, October 29, 2019 at 4:33:28 AM UTC-4, Dan S. MacAbre wrote:
Steve Weeks wrote:
On Monday, October 28, 2019 at 6:11:28 AM UTC-5, Dan S. MacAbre wrote:
The cones in the front wheel bearings are very pitted and creaky,
and I'd like to get some replacements... I can't find much on the web regarding this...

I've had good luck finding replacements he https://wheelsmfg.com/products/hub-parts/all-cones.html

Steve


Thanks! I'm sure I can find something there. I'll see if they ship to
the UK :-)

BTW, when they talk of the 'diameter' (8, 9, 9.5, 10mm) is that the
diameter of the axle /before/ tapping (i.e. the bare bar), or is it the
overall diameter of the threaded bits (which generally look a bit larger
to me), or the 'bottoms' of the thread grooves? Does (for example) 8mm
translate directly to the M8 metric thread size?

Thread sizes refer to the outside (or major) diameter of the male threads... but
see below.

Yes, threads are often larger than the rod or tube in its unthreaded condition.
That happens when the threads are rolled (pressed) into the metal, which is the
best way. Threads that are cut should be about the same diameter as the uncut
rod.

Except that threads tend to be just a little under their nominal size. That's
because the extreme tips of threads are difficult to make to a razor-sharp point,
and they don't help the strength of the thread anyway. So they may be formed to
have (say) 75% of the theoretical thread profile, omitting the 25% at the point.
That makes a nominal 8mm thread slightly less than true 8mm. How much less? It
varies.


I'd imagined that pressing the thread was cheaper, but less satisfactory
way of doing it, since it seems rather crude. But maybe things have
moved on since I was a lad :-)

In my workshop, I've hung a little chart that covers metric, U.S. and Whitworth
threads, ranked by major diameters. To identify a thread, I measure its major
diameter using calipers, then see which sizes it might be. I confirm by
measuring the thread pitch (that is, the number of threads per inch, or
millimeters per thread).

- Frank Krygowski


Does anything still use Whitworth now? I've a bit of a soft-spot for
Whitworth sizes since I used to mess about with old Britich bikes when I
was a lad (and still have a neglected one resting in the garage). My
Whitworth spanners don't get out much nowadays.

On 10/29/2019 10:53 AM, Dan S. MacAbre wrote:
AMuzi wrote:
On 10/29/2019 3:33 AM, Dan S. MacAbre wrote:
Steve Weeks wrote:
On Monday, October 28, 2019 at 6:11:28 AM UTC-5, Dan S.
MacAbre wrote:
The cones in the front wheel bearings are very pitted and
creaky,
and I'd like to get some replacements... I can't find
much on the web regarding this...

I've had good luck finding replacements he
https://wheelsmfg.com/products/hub-parts/all-cones.html

Steve


Thanks! I'm sure I can find something there. I'll see if
they ship to the UK :-)

BTW, when they talk of the 'diameter' (8, 9, 9.5, 10mm) is
that the diameter of the axle /before/ tapping (i.e. the
bare bar), or is it the overall diameter of the threaded
bits (which generally look a bit larger to me), or the
'bottoms' of the thread grooves? Does (for example) 8mm
translate directly to the M8 metric thread size?

It's the outer diameter of the thread, less thread
tolerance[1]. Standard bolt-on fronts are m8x1.0, QR
fronts are m9x1.0 and so on. Typical:

https://i394.photobucket.com/albums/.../DIN912_M6.jpg


Cheaper fat tire style bikes use 'heavy duty' fronts with
m9.5x1.0 and m10x1.0 of generally lower quality.

Going back to earlier times (older than your bike), a host
of variables ensue such as French metric m9x0.9,
Campagnolo 9f26, Raleigh 1/4-26W (measures 7.8mm) and mo

https://www.practicalmachinist.com/v...-standards.jpg


[1] Standard hardware runs well below 100% thread
engagement so the actual measurement across the thread
peaks will be less than the nominal size. see also:
http://www.yellowjersey.org/photosfr...t/FWTHREAD.JPG

and
https://www.engineersedge.com/thread...engagement.htm


Thanks again. I don't know whether it's because I live in
the UK, but most of the axle descriptions I see are in
Imperial sizes (i.e. 5/16" and 3/8"). I know there is
backward compatibility to consider, and that (of necessity)
most of these things will be the nearest approximate
equivalents; but I guess that the actual thread pitch is the
most important factor. So, do all bike components have
metric threads now? it may seem a silly question, but I have
worked with computer specialists from the US that have no
idea what (for example) a 10mm page margin looks like, and I
feel that there is some resistance over there. I quite
understand that, of course - there is still some resistance
over here :-)

Yes, all current products are standard (DIN, JIS, etc) metric.

1980s era Ofmega axle sets with the nicely precision ground
cone faces are threaded 9f26 front and 10f26 rear, a
55-degree WW thread also used by Gippiemme and Campagnolo
until 2000.

A Shimano or other common metric cone will stick on the axle
after two turns or so.

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

On 10/29/2019 11:00 AM, Dan S. MacAbre wrote:
Frank Krygowski wrote:
On Tuesday, October 29, 2019 at 4:33:28 AM UTC-4, Dan S.
MacAbre wrote:
Steve Weeks wrote:
On Monday, October 28, 2019 at 6:11:28 AM UTC-5, Dan S.
MacAbre wrote:
The cones in the front wheel bearings are very pitted
and creaky,
and I'd like to get some replacements... I can't find
much on the web regarding this...

I've had good luck finding replacements he
https://wheelsmfg.com/products/hub-parts/all-cones.html

Steve


Thanks! I'm sure I can find something there. I'll see
if they ship to
the UK :-)

BTW, when they talk of the 'diameter' (8, 9, 9.5, 10mm)
is that the
diameter of the axle /before/ tapping (i.e. the bare
bar), or is it the
overall diameter of the threaded bits (which generally
look a bit larger
to me), or the 'bottoms' of the thread grooves? Does
(for example) 8mm
translate directly to the M8 metric thread size?

Thread sizes refer to the outside (or major) diameter of
the male threads... but
see below.

Yes, threads are often larger than the rod or tube in its
unthreaded condition.
That happens when the threads are rolled (pressed) into
the metal, which is the
best way. Threads that are cut should be about the same
diameter as the uncut
rod.

Except that threads tend to be just a little under their
nominal size. That's
because the extreme tips of threads are difficult to make
to a razor-sharp point,
and they don't help the strength of the thread anyway. So
they may be formed to
have (say) 75% of the theoretical thread profile, omitting
the 25% at the point.
That makes a nominal 8mm thread slightly less than true
8mm. How much less? It
varies.


I'd imagined that pressing the thread was cheaper, but less
satisfactory way of doing it, since it seems rather crude.
But maybe things have moved on since I was a lad :-)

In my workshop, I've hung a little chart that covers
metric, U.S. and Whitworth
threads, ranked by major diameters. To identify a thread,
I measure its major
diameter using calipers, then see which sizes it might be.
I confirm by
measuring the thread pitch (that is, the number of threads
per inch, or
millimeters per thread).

- Frank Krygowski


Does anything still use Whitworth now? I've a bit of a
soft-spot for Whitworth sizes since I used to mess about
with old Britich bikes when I was a lad (and still have a
neglected one resting in the garage). My Whitworth spanners
don't get out much nowadays.

For most applications, a formed or cold-headed thread is
superior in every respect to a cut thread. Frank could
probably elaborate on why but it's certainly true.

If there's some current vehicle made with WW fasteners I
don't know of it. There are replica spares made to fit
classic British cars, motorcycles, bicycles etc, example:

https://mossmotors.com/

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

On Tuesday, October 29, 2019 at 12:00:59 PM UTC-4, Dan S. MacAbre wrote:
Frank Krygowski wrote:
On Tuesday, October 29, 2019 at 4:33:28 AM UTC-4, Dan S. MacAbre wrote:
Steve Weeks wrote:
On Monday, October 28, 2019 at 6:11:28 AM UTC-5, Dan S. MacAbre wrote:
The cones in the front wheel bearings are very pitted and creaky,
and I'd like to get some replacements... I can't find much on the web regarding this...

I've had good luck finding replacements he https://wheelsmfg.com/products/hub-parts/all-cones.html

Steve


Thanks! I'm sure I can find something there. I'll see if they ship to
the UK :-)

BTW, when they talk of the 'diameter' (8, 9, 9.5, 10mm) is that the
diameter of the axle /before/ tapping (i.e. the bare bar), or is it the
overall diameter of the threaded bits (which generally look a bit larger
to me), or the 'bottoms' of the thread grooves? Does (for example) 8mm
translate directly to the M8 metric thread size?

Thread sizes refer to the outside (or major) diameter of the male threads... but
see below.

Yes, threads are often larger than the rod or tube in its unthreaded condition.
That happens when the threads are rolled (pressed) into the metal, which is the
best way. Threads that are cut should be about the same diameter as the uncut
rod.

Except that threads tend to be just a little under their nominal size. That's
because the extreme tips of threads are difficult to make to a razor-sharp point,
and they don't help the strength of the thread anyway. So they may be formed to
have (say) 75% of the theoretical thread profile, omitting the 25% at the point.
That makes a nominal 8mm thread slightly less than true 8mm. How much less? It
varies.


I'd imagined that pressing the thread was cheaper, but less satisfactory
way of doing it, since it seems rather crude. But maybe things have
moved on since I was a lad :-)

That method of making threads is called "rolling." They use hardened dies of the
proper shape to press into the parent metal and cause it to flow upward to form
the peaks of the threads. It's actually much better than cutting the threads.
Rolled threads have a grain structure that flows into the threads, instead of
being sliced apart where a die or cutting tool cuts the valley. That makes
stronger threads.



In my workshop, I've hung a little chart that covers metric, U.S. and Whitworth
threads, ranked by major diameters. To identify a thread, I measure its major
diameter using calipers, then see which sizes it might be. I confirm by
measuring the thread pitch (that is, the number of threads per inch, or
millimeters per thread).

- Frank Krygowski


Does anything still use Whitworth now? I've a bit of a soft-spot for
Whitworth sizes since I used to mess about with old Britich bikes when I
was a lad (and still have a neglected one resting in the garage). My
Whitworth spanners don't get out much nowadays.

Here in the U.S., I think Whitworth threads have always been rare. I hardly ever
encounter them. But my chart does cover them.

- Frank Krygowski

On Tue, 29 Oct 2019 14:59:27 -0700 (PDT), Frank Krygowski
wrote:

On Tuesday, October 29, 2019 at 12:00:59 PM UTC-4, Dan S. MacAbre wrote:
Frank Krygowski wrote:
On Tuesday, October 29, 2019 at 4:33:28 AM UTC-4, Dan S. MacAbre wrote:
Steve Weeks wrote:
On Monday, October 28, 2019 at 6:11:28 AM UTC-5, Dan S. MacAbre wrote:
The cones in the front wheel bearings are very pitted and creaky,
and I'd like to get some replacements... I can't find much on the web regarding this...

I've had good luck finding replacements he https://wheelsmfg.com/products/hub-parts/all-cones.html

Steve


Thanks! I'm sure I can find something there. I'll see if they ship to
the UK :-)

BTW, when they talk of the 'diameter' (8, 9, 9.5, 10mm) is that the
diameter of the axle /before/ tapping (i.e. the bare bar), or is it the
overall diameter of the threaded bits (which generally look a bit larger
to me), or the 'bottoms' of the thread grooves? Does (for example) 8mm
translate directly to the M8 metric thread size?

Thread sizes refer to the outside (or major) diameter of the male threads... but
see below.

Yes, threads are often larger than the rod or tube in its unthreaded condition.
That happens when the threads are rolled (pressed) into the metal, which is the
best way. Threads that are cut should be about the same diameter as the uncut
rod.

Except that threads tend to be just a little under their nominal size. That's
because the extreme tips of threads are difficult to make to a razor-sharp point,
and they don't help the strength of the thread anyway. So they may be formed to
have (say) 75% of the theoretical thread profile, omitting the 25% at the point.
That makes a nominal 8mm thread slightly less than true 8mm. How much less? It
varies.


I'd imagined that pressing the thread was cheaper, but less satisfactory
way of doing it, since it seems rather crude. But maybe things have
moved on since I was a lad :-)

That method of making threads is called "rolling." They use hardened dies of the
proper shape to press into the parent metal and cause it to flow upward to form
the peaks of the threads. It's actually much better than cutting the threads.
Rolled threads have a grain structure that flows into the threads, instead of
being sliced apart where a die or cutting tool cuts the valley. That makes
stronger threads.



In my workshop, I've hung a little chart that covers metric, U.S. and Whitworth
threads, ranked by major diameters. To identify a thread, I measure its major
diameter using calipers, then see which sizes it might be. I confirm by
measuring the thread pitch (that is, the number of threads per inch, or
millimeters per thread).

- Frank Krygowski


Does anything still use Whitworth now? I've a bit of a soft-spot for
Whitworth sizes since I used to mess about with old Britich bikes when I
was a lad (and still have a neglected one resting in the garage). My
Whitworth spanners don't get out much nowadays.

Here in the U.S., I think Whitworth threads have always been rare. I hardly ever
encounter them. But my chart does cover them.

- Frank Krygowski

Having once owned a "British motorcycle" I can assure you that
Whitworth threaded fasteners are rare :-)
--
cheers,

John B.

AMuzi wrote:
On 10/29/2019 10:53 AM, Dan S. MacAbre wrote:
AMuzi wrote:
On 10/29/2019 3:33 AM, Dan S. MacAbre wrote:
Steve Weeks wrote:
On Monday, October 28, 2019 at 6:11:28 AM UTC-5, Dan S.
MacAbre wrote:
The cones in the front wheel bearings are very pitted and
creaky,
and I'd like to get some replacements...* I can't find
much on the web regarding this...

I've had good luck finding replacements he
https://wheelsmfg.com/products/hub-parts/all-cones.html

Steve


Thanks!* I'm sure I can find something there.* I'll see if
they ship to the UK :-)

BTW, when they talk of the 'diameter' (8, 9, 9.5, 10mm) is
that the diameter of the axle /before/ tapping (i.e. the
bare bar), or is it the overall diameter of the threaded
bits (which generally look a bit larger to me), or the
'bottoms' of the thread grooves?* Does (for example) 8mm
translate directly to the M8 metric thread size?

It's the outer diameter of the thread, less thread
tolerance[1]. Standard bolt-on fronts are m8x1.0, QR
fronts are m9x1.0 and so on. Typical:

https://i394.photobucket.com/albums/.../DIN912_M6.jpg



Cheaper fat tire style bikes use 'heavy duty' fronts with
m9.5x1.0 and m10x1.0 of generally lower quality.

Going back to earlier times (older than your bike), a host
of variables ensue such as French metric m9x0.9,
Campagnolo 9f26, Raleigh 1/4-26W (measures 7.8mm) and mo

https://www.practicalmachinist.com/v...-standards.jpg



[1] Standard hardware runs well below 100% thread
engagement so the actual measurement across the thread
peaks will be less than the nominal size. see also:
http://www.yellowjersey.org/photosfr...t/FWTHREAD.JPG

and
https://www.engineersedge.com/thread...engagement.htm



Thanks again.* I don't know whether it's because I live in
the UK, but most of the axle descriptions I see are in
Imperial sizes (i.e. 5/16" and 3/8").* I know there is
backward compatibility to consider, and that (of necessity)
most of these things will be the nearest approximate
equivalents; but I guess that the actual thread pitch is the
most important factor.* So, do all bike components have
metric threads now? it may seem a silly question, but I have
worked with computer specialists from the US that have no
idea what (for example) a 10mm page margin looks like, and I
feel that there is some resistance over there. I quite
understand that, of course - there is still some resistance
over here :-)

Yes, all current products are standard (DIN, JIS, etc) metric.

1980s era Ofmega axle sets with the nicely precision ground cone faces
are threaded 9f26 front and 10f26 rear, a 55-degree WW thread also used
by Gippiemme and Campagnolo until 2000.

A Shimano or other common metric cone will stick on the axle after two
turns or so.


I found that some cones I'd saved off other bikes did indeed get stuck
after a few turns. I got a replacement axle set (axle, cones, skewer)
hoping that they were 'all the same'. Maybe they are standardised now,
otherwise why even sell such things? But those new sets just ended up
pushing the balls out of the old cups after a short while.

Still, I now have some specific threads to look for, so thanks for that.
This is certainly one of the more informative groups :-)

Frank Krygowski wrote:
On Tuesday, October 29, 2019 at 12:00:59 PM UTC-4, Dan S. MacAbre wrote:
Frank Krygowski wrote:
On Tuesday, October 29, 2019 at 4:33:28 AM UTC-4, Dan S. MacAbre wrote:
Steve Weeks wrote:
On Monday, October 28, 2019 at 6:11:28 AM UTC-5, Dan S. MacAbre wrote:
The cones in the front wheel bearings are very pitted and creaky,
and I'd like to get some replacements... I can't find much on the web regarding this...

I've had good luck finding replacements he https://wheelsmfg.com/products/hub-parts/all-cones.html

Steve


Thanks! I'm sure I can find something there. I'll see if they ship to
the UK :-)

BTW, when they talk of the 'diameter' (8, 9, 9.5, 10mm) is that the
diameter of the axle /before/ tapping (i.e. the bare bar), or is it the
overall diameter of the threaded bits (which generally look a bit larger
to me), or the 'bottoms' of the thread grooves? Does (for example) 8mm
translate directly to the M8 metric thread size?

Thread sizes refer to the outside (or major) diameter of the male threads... but
see below.

Yes, threads are often larger than the rod or tube in its unthreaded condition.
That happens when the threads are rolled (pressed) into the metal, which is the
best way. Threads that are cut should be about the same diameter as the uncut
rod.

Except that threads tend to be just a little under their nominal size. That's
because the extreme tips of threads are difficult to make to a razor-sharp point,
and they don't help the strength of the thread anyway. So they may be formed to
have (say) 75% of the theoretical thread profile, omitting the 25% at the point.
That makes a nominal 8mm thread slightly less than true 8mm. How much less? It
varies.


I'd imagined that pressing the thread was cheaper, but less satisfactory
way of doing it, since it seems rather crude. But maybe things have
moved on since I was a lad :-)

That method of making threads is called "rolling." They use hardened dies of the
proper shape to press into the parent metal and cause it to flow upward to form
the peaks of the threads. It's actually much better than cutting the threads.
Rolled threads have a grain structure that flows into the threads, instead of
being sliced apart where a die or cutting tool cuts the valley. That makes
stronger threads.



In my workshop, I've hung a little chart that covers metric, U.S. and Whitworth
threads, ranked by major diameters. To identify a thread, I measure its major
diameter using calipers, then see which sizes it might be. I confirm by
measuring the thread pitch (that is, the number of threads per inch, or
millimeters per thread).

- Frank Krygowski


Does anything still use Whitworth now? I've a bit of a soft-spot for
Whitworth sizes since I used to mess about with old Britich bikes when I
was a lad (and still have a neglected one resting in the garage). My
Whitworth spanners don't get out much nowadays.

Here in the U.S., I think Whitworth threads have always been rare. I hardly ever
encounter them. But my chart does cover them.

- Frank Krygowski


Makes sense. I supposed it's a bit like wrought iron vs. cast iron.