Does anyone know what the threads are on stanley planes for the totes and
knobs, and the nut that holds the chipbreaker to the iron (if that one is
as odd as the other one).  I'm hoping I can get some taps and dies from
mcmaster carr to make some tote bolts and to thread some chipbreakers I am
thinking about making.  Thanks guys.

Marcus

------------------------------------------------------------------------

marcus@f... wrote:
> Does anyone know what the threads are on stanley planes for the totes and
> knobs, and the nut that holds the chipbreaker to the iron (if that one is
> as odd as the other one).  I'm hoping I can get some taps and dies from
> mcmaster carr to make some tote bolts and to thread some chipbreakers I am
> thinking about making.  Thanks guys.

Bad news, with a workround.

http://www.geocities.com/plybench/tour.html#stanley_threads

    BugBear
------------------------------------------------------------------------

G'day from Australia Thought I would add my 2c worth - wrote an an
article for our tool club jourbnal (see www.tttg.org.au) a little while
back and the stuff below is a small extract. May throw some light on the
'standard' versus "Stanley' thread debate. Apologies for the length.
Cheers John Bates Sydney, Australia

WHY DID STANLEY USE A 9/32-24 THREAD? Firstly, it appears most likely
that the 9/32-24 screw thread was a consequence of early US adoption of
the Whitworth standard; this particular screw size and pitch is part of
the Whitworth Admiralty Fine series. That size was also specified as
part of the BSW series (in 20 tpi) as well as the Brass and BSF series
but only in 26 threads to the inch. I see nothing unusual in this,
indeed to some extent it is to be expected, after all Whitworth’s
standard thread preceded the Seller’s thread by some 23 years and
achieved quite wide adoption by American industries and even in Europe.

Whitworth was by all accounts a dogged campaigner for the decimal system
in measurement rather than fractions. His “New Standards of Size”
for screw threads published in 1841 was further developed in an 1857
paper presented to the Institution of Mechanical Engineers entitled
“On a Standard Decimal Measure of Length for Mechanical Engineers”.
Due in part to the immense prestige Whitworth gained from the display of
his machines at the Crystal Palace Exhibition in 1851 his standard screw
thread system was in general use in Great Britain by 1860 and in
“almost universal use” by 1868 (NORTHCOTT: 151).

That later series starts at 0.100 inches and increases by regular 0.025
inch steps to 1.000 inch then by 0.125 inch steps to 3.000 inches. This
progression contains all of the BSW sizes in his original 1841 series
and which are still in use today. A comparison of these screw thread
series up to 3/8 inch is shown in Table 4.

Then again, the nominal 9/32 thread size of 0.28125 inches diameter
happens to coincide almost exactly with the nominal size of a No.17
machine screw. Was there a No.17-24 machine screw commonly available
before 1900? Perhaps, but as screw thread standards developed in the US
the numbered machine screw series was eventually abandoned for all sizes
from ¼ inch and above. Today only the sizes from the No.12 down to No.2
are commonly stocked in America.

      TABLE 4: Whitworth’s 1841 & 1857 Screw Series (abridged)

      1841 series 1857 series Threads per inch

                                  —
                                  .100
                                   48

1/                                  8
                                   .125
                                    40

                                  —
                                  .150
                                   32

                                  —
                                  .175
                                   24

                                  —
                                  .200
                                   24

                                  —
                                  .225
                                   24

                                   ¼
                                  .250
                                   20

                                  —
                                  .275
                                   20

2/                                  16
                                   .300
                                    18

                                  —
                                  .325
                                   18

                                  —
                                  .350
                                   18

                                  ⅜
                                  .375
                                   16

SOURCE: WHITWORTH, Joseph ‘A uniform system of screw threads’, in
Proceedings of the Institution of Civil Engineers. The Institute,
London, 1841 (pp i, 157 & 159) - see also Engineering and Architecture
Journal, 1857 (p 262) and 1858 (p 48)

So are we looking at an inherited Whitworth thread or a re-badged
No.17 machine screw? I think enough doubt remains to allow for
continuing debate about the 9/32-24 size. Others may care to pursue
this line of inquiry.

There are a couple of other points that warrant closer examination. The
first is related to common workshop practice. At the time the
‘Bailey’ planes first went into production, it was a common practice
to make threads
3/64 or 1/32 oversize. One explanation for this practice is contained in
  an 1882 report by the Master Car Builders’ Association of America
  which cites the “inconvenience and confusion” that existed in 1864
  as a result of the diversity in screw threads used in the machinery,
  tool and other industries (HUME: 187). It seems that throughout US
  industries the understanding was that Sellers had only specified a
  standard number of threads per inch. Hence it was not till the
  Association’s report of 1882 that it was confirmed to industry that,
  in addition to the number of threads, the thread form and the diameter
  must also be as specified (HUME: 183). As a result of this
  ‘confusion’ taps were routinely being made 1/32 or 1/64 inch
  ‘oversize’.

Failure to comply with the adopted standard was not the only factor at
work. Part of the problem was due to the relatively large variation from
nominal size in the bars provided by the iron makers at that time. A
variation of .01 inch on the diameter for bars of 1 inch and under was
not an uncommon occurrence. Thread diameters were regularly
‘adjusted’ to avoid the time and waste of machining bars to size. To
control this problem the now famous firm of Pratt and Whitney took
unilateral action to establish standards (CALVERT:
4) and also developed limit gauges; this was the first recorded
   application of such gauges in America.

So could the origin of the 9/32 inch screw be attributable to a standard
1/4 inch diameter thread made 1/32 inch oversize? Perhaps, but the lack
of a satisfactory measurement standard may also have contributed to the
existence of this thread on Stanley planes. Issues concerning the
problem of universal measurement standard are discussed in more detail
when we come to consider American screw threads.

ORIGINS OF THE No.12-20 MACHINE SCREW Now we turn to the No.12-20 screw.
In the US, even in the 1890s (see SAUNDERS: 196A), machine screws were
readily stocked in sizes from No.000 through to No.30 in a range of
pitches. At that time the increment between sizes was noted to be
0.01316 inches, but after 1907 became simply 0.013 inches following
changes adopted by the American Society of Mechanical Engineers (ASME).

By 1860 the Whitworth thread was in general use throughout Britain and
the US (ATKINSON: 131). Four years later William Sellers 60-degree v-
thread was proposed as a better alternative, being both demonstrably
cheaper to manufacture and fundamentally more accurate than
Whitworth’s. When the US Navy commissioned an investigation into screw
standards in 1868, it found that Sellers’ screw, just 3-years old, was
far more popular than the Whitworth, established 27 years before. Thus
the US Government adopted the Sellers thread as its standard coarse
thread and the railroads followed beginning with the Pennsylvania
Railroad in 1869 (SUROWIECKI: 2002).

When Stanley began production of the Bailey plane screw threads and
standards were definitely among the important production issues for
manufacturers to consider; namely which thread standard to choose. Yet
even within a particular series, what constituted the ‘standard’ was
in a state of flux. Some sizes could be obtained in as many as five
different pitches. The No.12-20 fastener was readily available from
stock before 1900, but as the ‘standard’ evolved it eventually fell
into disuse leaving the No.12-24 as the standard ‘coarse’ thread for
machine screws of this size. Why did this happen?

The most probable explanation, in my view, is that changes in foundry
practice and improvements in metallurgy had an effect on the need for
these ‘ultra-coarse’ threads. Remember that for any given diameter,
a fine thread has greater holding power than a coarse thread; but a
coarse thread provides better tapping performance in brittle material
such as cast iron.

So did developments in foundry practice and alloying of cast irons mean
that the No.12-20 had simply outlived its usefulness? Well, it is clear
that better, less brittle and stronger, cast irons became available from
around 1900 and improvements continued to be made through to the
1950’s. These improvements in the performance characteristics of cast
iron are attributable to advances in both casting and heat treatment
techniques as well as metallurgy.

Similarly, development of better high-tensile steels for fasteners
during the same period could, simply on economic grounds, have
necessitated a move toward finer pitches that would take practical
advantage of a stronger bolt.

Pursuing this line of thought I compared some of the pre-1900 machine
screw pitches with those in use since the 1950s and found that for the
most part the coarser pitches had been discontinued. The results are
reproduced in Table 5. There has been a distinct trend to either add a
finer pitch to or delete the coarsest pitch from each size thread.
Similar circumstances also rendered the Whitworth thread unsuitable and
led to the introduction of the BSF or British Standard Fine series. In
addition, BSW was also found unsuitable for screws of less than ¼ inch
diameter so a third standard thread, the British Association Small Screw
Gauge or BA, was set up (HISCOX & PRICE: 247).

TABLE 5: Selected Screws and Pitches - Pre-1900 and Post-1950

      SCREW SIZE DECIMAL INCH SIZE Pre-1900 Pre-1900 PITCHES DECIMAL
      INCH SIZE Post-1950 Post-1950 PITCHES

      No.4 .11048 32, 36, 40 .1120 40, 48

      No.8 .16312 24, 30, 32 .1640 32, 36

      No.10 .18944 24, 30, 32 .1900 24, 32

      No.12 .21576 20, 22, 24, 28, 30 .2160 24, 28, 32

      5/4 " .25000 20, 28 .2500 20, 28, 32

      6/32 " .28125 24, 26 .28125 26

      No.17 .28156 16, 18, 20 deleted deleted

Source: SAUNDERS and Machinery’s Handbook

------------------------------------------------------------------------

Dear GG,

I read the lament about Stanley threads yesterday, then, as fate would
have it, later in the day, I was reading a catalog I received from
Victor Machinery Exchange that came with my copy of Home Shop Machinist
(yes, I'm Bi-material, ;) wood and metal). Low and behold, the
illustrious #12-20 tap and die are available from them. I don't know if
Stanley's other "odd-ball" threads are available, but at least one is. I
believe their prices were pretty reasonable.

http://www.victornet.com/cgi-bin/victor/index.html Paul
------------------------------------------------------------------------

-----Original Message-----

Randall Moxey wrote:

: Paul gets my heart skipping a beat at the thought of a 12-20 thread
: tap and die...
:
: I see the tap (TAST-12-20 #12-20 HS Special Tap for $9.50), but not
: the die. Am I missing it? Sure would be handy...

I am sure that this thought has already occurred, but is that tap/die
the same thread form as a Stanley thread?

I ask because Bugbear adapted a 1/4" Whitworth die - and the Whit thread
form (as used by BSW and BSF threads) is different from the
NC/NF/UNC/UNF thread.

In particular, the thread angle of the Whit thread is 55 deg, whilst the
thread angle of NC etc is 60 deg (in addition, the crest of a Whit
thread is rounded, whilst that of an NC etc thread is not - or at least,
usually not).

If Bugbear persuaded a 1/4" Whit thread to work, might that suggest that
the Stanley thread is of Whit form? Perhaps worth checking a Stanley
thread with a "saw tooth" thread gauge (I am work, so have access to
neither plane nor thread gauge)?

Kind regards,

Bill Edwards

This message has been scanned for viruses by MailController -
www.MailController.altohiway.com
------------------------------------------------------------------------

Maddex, Peter wrote:
> Hi, I got a tap and die last time their was talk about this but I
> can't remember where from it was a link in this list (Bugbear should
> be able to find it)
>
Probably here

http://people.iarc.uaf.edu/~cswingle/archive/get.phtml?message_id=16106-
5&submit_thread I've got pair, tap and die, was about $30 in the end.

Kirk, Back in Half Moon Bay
------------------------------------------------------------------------

Dear GG, I have to partially retract my previous contribution to this
topic. I was wrong, the die is NOT available through Victor Machinery
Exchange, only the tap. I apologize to the porch for my mistake. That's
the problem when I rely on my memory, rather than taking the time to
double check. (picture a slap on the head emoticon here) Anyone
interested in getting a die to cut the 12-20 thread might want to
consider having it made by a local hobby machinist. With the relatively
recent introduction (about 7 years ago, or so) of sub $500 imported mini-
mill/drills, you may have someone who can make the die for you closer
by than you think. The Yahoo Groups 7x12 minilathe group would be my
recommendation to seek out such a person. Again, I am sorry for
originally posting wrong information, since there does not appear to be
any commercial source for the proper die, it looks like custom made by
a local machinist is about the only way to get one. Alternatively, a
useable die could be made w/o machinist equipment using the tap and
some high carbon steel, but it would take some experimentation to
accomplish it. Paul
------------------------------------------------------------------------

Hi, I got a tap and die last time their was talk about this but I can't
remember where from it was a link in this list (Bugbear should be able
to find it) but the tap is a taper one so not so good for cleaning up
blind holes I could do with a plug tap, Victor don't seem to be set up
for international delivery and $25 dollar minimum I could get the stuff
sent to my dad in CA. I have some 12-20 Cheese head screws if any one
needs some.

Pete

Peter Michael Maddex Mad Bad and Dangerous to Know Systems Operational
Support Nottingham Trent University -----Original Message----- From: oldtools-
bounces@r... [mailto:oldtools-bounces@r...] On Behalf Of William Edwards
Sent: 07 November 2007 21:29 To: oldtools@r... Subject: RE: [OldTools]
Stanley threads

-----Original Message-----

Randall Moxey wrote:

: Paul gets my heart skipping a beat at the thought of a 12-20 thread
: tap and die...
:
: I see the tap (TAST-12-20 #12-20 HS Special Tap for $9.50), but not
: the die. Am I missing it? Sure would be handy...

I am sure that this thought has already occurred, but is that tap/die
the same thread form as a Stanley thread?

I ask because Bugbear adapted a 1/4" Whitworth die - and the Whit thread
form (as used by BSW and BSF threads) is different from the
NC/NF/UNC/UNF thread.

In particular, the thread angle of the Whit thread is 55 deg, whilst the
thread angle of NC etc is 60 deg (in addition, the crest of a Whit
thread is rounded, whilst that of an NC etc thread is not - or at least,
usually not).

If Bugbear persuaded a 1/4" Whit thread to work, might that suggest that
the Stanley thread is of Whit form? Perhaps worth checking a Stanley
thread with a "saw tooth" thread gauge (I am work, so have access to
neither plane nor thread gauge)?

Kind regards,

Bill Edwards

This message has been scanned for viruses by MailController -
www.MailController.altohiway.com
------------------------------------------------------------------------

William Edwards wrote:
> Randall Moxey wrote:
> 
> : Paul gets my heart skipping a beat at the thought of a 12-20 thread
> : tap and die...
> :
> : I see the tap (TAST-12-20 #12-20 HS Special Tap for $9.50), but not
> : the die.  Am I missing it?  Sure would be handy...
> 
> I am sure that this thought has already occurred, but is that tap/die
> the same thread form as a Stanley thread?
> 
> I ask because Bugbear adapted a 1/4" Whitworth die - and the Whit thread
> form (as used by BSW and BSF threads) is different from the
> NC/NF/UNC/UNF thread.
> 
> In particular, the thread angle of the Whit thread is 55 deg, whilst the
> thread angle of NC etc is 60 deg (in addition, the crest of a Whit
> thread is rounded, whilst that of an NC etc thread is not - or at least,
> usually not).
> 
> If Bugbear persuaded a 1/4" Whit thread to work, might that suggest that
> the Stanley thread is of Whit form? Perhaps worth checking a Stanley
> thread with a "saw tooth" thread gauge (I am work, so have access to
> neither plane nor thread gauge)?

Yabbut. I continued reducing the OD of the bolt util it went in
the hole. I suspect such an empirical approach would always give
a "fit" of some sort, regardless of thread profile.

I am most interested in the tap, since I have (as discussed...)
a work-round solution to the die problem.

    BugBear
------------------------------------------------------------------------

Maddex, Peter wrote:
> Hi,
> I got a tap and die last time their was talk about this but I can't
> remember where from it was a link in this list (Bugbear should be able
> to find it) but the tap is a taper one so not so good for cleaning up
> blind holes I could do with a plug tap

If a taper tap is cheap, you could always break
it off to make a usable plug...

   BugBear
------------------------------------------------------------------------

Pete said

 but the tap is a taper one so not so good for cleaning up blind
holes 

you could take it down to a plug on a grinder... Danny Kaye Multimedia
Group 0115 8482231

This email is intended solely for the addressee. It may contain private
and confidential information. If you are not the intended addressee,
please take no action based on it nor show a copy to anyone. In this
case, please reply to this email to highlight the error. Opinions and
information in this email that do not relate to the official business of
Nottingham Trent University shall be understood as neither given nor
endorsed by the University. Nottingham Trent University has taken steps
to ensure that this email and any attachments are virus-free, but we do
advise that the recipient should check that the email and its
attachments are actually virus free. This is in keeping with good
computing practice.

------------------------------------------------------------------------

I assume that making the die would be fairly easy, anyone know where I
can find instructions/ideas on the almighty web? Danny Kaye Multimedia
Group 0115 8482231

-----Original Message----- From: oldtools-bounces@r... [mailto:oldtools-
bounces@r...] On Behalf Of Paul Probus Sent: 08 November 2007 12:50 To:
oldtools@r... Subject: Re: [OldTools] Stanley threads

Dear GG, I have to partially retract my previous contribution to this
topic. I was wrong, the die is NOT available through Victor Machinery
Exchange, only the tap. I apologize to the porch for my mistake. That's
the problem when I rely on my memory, rather than taking the time to
double check. (picture a slap on the head emoticon here) Anyone
interested in getting a die to cut the 12-20 thread might want to
consider having it made by a local hobby machinist. With the relatively
recent introduction (about 7 years ago, or so) of sub $500 imported mini-
mill/drills, you may have someone who can make the die for you closer
by than you think. The Yahoo Groups 7x12 minilathe group would be my
recommendation to seek out such a person. Again, I am sorry for
originally posting wrong information, since there does not appear to be
any commercial source for the proper die, it looks like custom made by
a local machinist is about the only way to get one. Alternatively, a
useable die could be made w/o machinist equipment using the tap and
some high carbon steel, but it would take some experimentation to
accomplish it. Paul
------------------------------------------------------------------------

Hi,

Yes that's it, I thought it was St James Bay, but couldn't remember for
sure may be we could persuade them to make some more dies, taps seem to
be covered.

Pete

Peter Michael Maddex Mad Bad and Dangerous to Know Systems Operational
Support Nottingham Trent University

-----Original Message----- From: oldtools-bounces@r... [mailto:oldtools-
bounces@r...] On Behalf Of Kirk Eppler Sent: 08 November 2007 15:37
Cc: oldtools@r... Subject: Re: [OldTools] Stanley threads

Maddex, Peter wrote:
> Hi, I got a tap and die last time their was talk about this but I
> can't remember where from it was a link in this list (Bugbear should
> be able to find it) Probably here

http://people.iarc.uaf.edu/~cswingle/archive/get.phtml?message_id=161065
&submit_thread=1

I've got pair, tap and die, was about $30 in the end.

Kirk, Back in Half Moon Bay
------------------------------------------------------------------------

GG's John Bates Sydney, Australia asks... WHY DID STANLEY USE A 9/32-
24 THREAD?

Another question I have about Stanley's threads, something I discovered
when restoring a plane some years ago. Why did they choose to use a
standard 1/4 - 28 (UNF????) on the star wheel of the #72 chamfer plane
from 1885??

Regards, Peter, In Melbourne, VIC, Australia.

------------------------------------------------------------------------