Gear hanger thread

Al said:

I need to retap a gear hanger lug to take the big bolt for the
derailure.
www.sheldonbrown.com shows this as 10mm x 1mm, which I believe is an
unusually fine pitch.
Can anybody confirm or deny this, please?

Cycle threads are alway finer than "industrial"
threads, to resist coming undone under vibration.

http://www.voc.uk.com/archives/html/threads.html

I can't confirm or deny this particular piece of
into though.

BugBear

Al said:

I need to retap a gear hanger lug to take the big bolt for the
derailure.
www.sheldonbrown.com shows this as 10mm x 1mm, which I believe is an
unusually fine pitch.
Can anybody confirm or deny this, please?

I can confirm that a standard M10 bolt doesn't fit a replaceable hanger's
derailleur mounting hole.

Park Tools' 10x1mm TAP-10 is intended for derailleur hangers. See
http://www.parktool.com/tools/TAP_10.shtml

~PB

bugbear said:

Cycle threads are alway finer than "industrial"
threads, to resist coming undone under vibration.

Standard metric (coarse) threads are used for plenty of things on bikes.

~PB

bugbear said:

Cycle threads are alway finer than "industrial"
threads, to resist coming undone under vibration.
I can't confirm or deny this particular piece of
into though.

Er, I can. Bikes use standard threads. Anything else would be far too
difficult.

Guy
--
May contain traces of irony. Contents liable to settle after posting.
http://www.chapmancentral.co.uk

88% of helmet statistics are made up, 65% of them at Washington
University

"Al" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

I need to retap a gear hanger lug to take the big bolt for the
derailure.
www.sheldonbrown.com shows this as 10mm x 1mm, which I believe is an
unusually fine pitch.
Can anybody confirm or deny this, please?

It certainly is 10mm x 1mm. Sheldon wouldn't lie :-)

I wouldn't call this an unusually fine pitch. Most threads on a bike are
1mm pitch.

I don't think it's worth buying the tap for a one-off. Take it to your bike
shop and they'll do it in no time.

Ian

Just zis Guy said:

bugbear said:

Cycle threads are alway finer than "industrial"
threads, to resist coming undone under vibration.
I can't confirm or deny this particular piece of
into though.

Er, I can. Bikes use standard threads. Anything else would be far too
difficult.

Heh. Bikes use standard bike threads.
http://homepages.tesco.net/~A10bsa/bscbot.htm

I have a rather nice 1935 catalogue listing a full
set of taps and dies.

BugBear

bugbear said:

Quoted message said:

Er, I can. Bikes use standard threads. Anything else would be far
too difficult.

Quoted message said:

Heh. Bikes use standard bike threads.
http://homepages.tesco.net/~A10bsa/bscbot.htm

Oh, well, if you want to go back that far...

My laundry collection was all sourced at the local ironmongers with no
special orders required.

Guy
--
May contain traces of irony. Contents liable to settle after posting.
http://www.chapmancentral.co.uk

88% of helmet statistics are made up, 65% of them at Washington
University

Al said:

I need to retap a gear hanger lug to take the big bolt for the
derailure.
www.sheldonbrown.com shows this as 10mm x 1mm, which I believe is an
unusually fine pitch.
Can anybody confirm or deny this, please?

True - and hub axles are the same thread, so now you know why it has to
be "fine".

In message <[email hidden]>

(Al) said:

I need to retap a gear hanger lug to take the big bolt for the
derailure.
www.sheldonbrown.com shows this as 10mm x 1mm, which I believe is an
unusually fine pitch.
Can anybody confirm or deny this, please?

Yes M10x1.0

The 'normal' for M10 in Europe is M10x1.5, in Japan the norm is
M10x1.25.

Tip M10x 1.0 is the smaller spark plug thread as used on many
lawnmowers some motor cycles etc and is quite common in tap sets

Gwyn

Quoted message said:

Thanks in advance,
Al
Cambridge UK

Gwyn Oakley <[email hidden]> wrote in message news:<[email hidden]>...

Quoted message said:

In message <[email hidden]>

(Al) said:

I need to retap a gear hanger lug to take the big bolt for the
derailure.
www.sheldonbrown.com shows this as 10mm x 1mm
:

Yes M10x1.0

The 'normal' for M10 in Europe is M10x1.5, in Japan the norm is
M10x1.25.

Tip M10x 1.0 is the smaller spark plug thread as used on many
lawnmowers some motor cycles etc and is quite common in tap sets
:

Thanks to everyone who replied, and particularly for Gwyn's sparkplug
thread tip - we probably already have the tap we'll need.

Al.

correct, though I think Campag use a slightly different pitch (26tpi),
but not enough to cause a problem

Al said:

I need to retap a gear hanger lug to take the big bolt for the
derailure.
www.sheldonbrown.com shows this as 10mm x 1mm, which I believe is an
unusually fine pitch.
Can anybody confirm or deny this, please?

Thanks in advance,
Al
Cambridge UK

Pete whelan said:

correct, though I think Campag use a slightly different pitch (26tpi),
but not enough to cause a problem

Why would they use a different pitch? Campag make their derailleurs for
use with standard hangers.

~PB

"Pete Biggs" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Pete whelan said:

correct, though I think Campag use a slightly different pitch (26tpi),
but not enough to cause a problem

Why would they use a different pitch? Campag make their derailleurs for
use with standard hangers.

Cos they like to do things their own way.

Campag hangers are 26tpi, as Pete W says.

Normally not a problem but if you are trying to thread a 1mm pitch aluminium
bolt into a 26tpi aluminium hanger then you might get into difficulties.
Better to re-thread it with a 1mm tap.

Ian

"Al" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Thanks to everyone who replied, and particularly for Gwyn's sparkplug
thread tip - we probably already have the tap we'll need.

If not these folks do:
http://www.cromwell.co.uk/browse?page=2

Rgds,
Pete

A1 - I've got a M10 x 1mm tap and I am about 18 miles form Cambridge.
If you need it I'll ride down with it one evening. email me from my
website: http://xntrick.co.uk

Wobbly John