I have a small job that requires threads be cut on the OD of a round rod. I
have looked all around for a chart that indicates the outside diameter a rod
should be when using a die to cut threads. Something along the lines of a
tap drill chart, but for dies? Any takers?

TIA - Ryan

"Ryan" wrote in message
news:c9DJb.147078$ss5.14531@clgrps13...
I have a small job that requires threads be cut on the OD of a round rod.
I
have looked all around for a chart that indicates the outside diameter a
rod
should be when using a die to cut threads. Something along the lines of a
tap drill chart, but for dies? Any takers?

TIA - Ryan


The same size as the hole they are going into.

--
www.bribieisland4x4hire.com
VW Kombi Camper Buy Backs
Landcruiser Troopy - Toyota Hilux Crew Cab
Mitsubishi Pajero - Landrover V8 Swag Camper

The diameter of the rod should be the nominal dimension of the thread. So
if you wanted to cut 1/4 x 20 threads you would start with a 1/4" rod. In
actual practice the diameter of the rod should be a few thousandths of an
inch smaller than the nominal dimension.

What size threads do you need to cut?

--
Roger Shoaf
If you are not part of the solution, you are not dissolved in the solvent.

"Ryan" wrote in message
news:c9DJb.147078$ss5.14531@clgrps13...
I have a small job that requires threads be cut on the OD of a round rod.
I
have looked all around for a chart that indicates the outside diameter a
rod
should be when using a die to cut threads. Something along the lines of a
tap drill chart, but for dies? Any takers?

TIA - Ryan

Thanks Roger Shoaf, that makes sense. I need to make it 5/16 x 32. Sounds
like that might workout because the diameter of the rod is .311 right now.



"Roger Shoaf" wrote in message
...
The diameter of the rod should be the nominal dimension of the thread. So
if you wanted to cut 1/4 x 20 threads you would start with a 1/4" rod. In
actual practice the diameter of the rod should be a few thousandths of an
inch smaller than the nominal dimension.

What size threads do you need to cut?

--
Roger Shoaf
If you are not part of the solution, you are not dissolved in the solvent.

"Ryan" wrote in message
news:c9DJb.147078$ss5.14531@clgrps13...
I have a small job that requires threads be cut on the OD of a round
rod.
I
have looked all around for a chart that indicates the outside diameter a
rod
should be when using a die to cut threads. Something along the lines of
a
tap drill chart, but for dies? Any takers?

TIA - Ryan

Roger Martin wrote: The same size as the hole they are going into.
^^^^^^^^^^
I believe that dies are sized so that they will cut proper threads on rod
whose OD is the nominal thread size. ie, if you are threading 1/4" rod, and
use a 1/4-20 or 1/4-28 die, you will get a proper thread.

If the top of the thread is slightly truncated because the diameter is
a little less than the nominal diameter, the strength is almost the
same and the effort to cut the threads is greatly reduced. The
Machinery Handbook has tables with dimensions for various classes of
threads.

Dan


"Ryan" wrote in message news:7kEJb.148429$ss5.95526@clgrps13...
Thanks Roger Shoaf, that makes sense. I need to make it 5/16 x 32. Sounds
like that might workout because the diameter of the rod is .311 right now.

In article , Dan Caster says...

If the top of the thread is slightly truncated because the diameter is
a little less than the nominal diameter, the strength is almost the
same and the effort to cut the threads is greatly reduced. The
Machinery Handbook has tables with dimensions for various classes of
threads.

Another point is, it's a lot easier to avoid drunken
threads from a die, if the stock is turned way undersized
for a length equal to about one diameter or so. This
allows the die to start cutting true, and in most cases
the first bit of undersized stock can be trimmed off
afterwards.

This is especially helpful with large diameter or
coarse threads.

Jim

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"jim rozen" wrote in message
...

This is especially helpful with large diameter or
coarse threads.

And if you're wondering how to find out them wee diameters with numbered
machine screws, a number 0 is .060" diameter, and every number is .013"
more.

Regards,

Robin

"Ryan" wrote in message
news:7kEJb.148429$ss5.95526@clgrps13...
Thanks Roger Shoaf, that makes sense. I need to make it 5/16 x 32.
Sounds
like that might workout because the diameter of the rod is .311 right now.


That should work OK, just make sure there is a lead on the end of the rod
and use cutting oil. Stop and reverse to break the chips every 1/2 turn.
Be sure to start the threads using the large side of the die.

--
Roger Shoaf
If you are not part of the solution, you are not dissolved in the solvent..

The bolt or rod size for threading is given by the formula:

nominal diameter - (0.216/pitch)

Whe nominal diameter is the stated diameter expressed as a decimal, such
as 1/4 is 0.250, etc. Pitch is the number of threads per inch.; for example
an 18 pitch would be 1/18 or 0.056, a 20 pitch would be 1/20 or 0.05, etc.

For a worked out example, consider the rod or bolt size to thread 3/8 - 24.
The bolt should be:

0.375 - (0.216 / 24) this equals 0.366. For a 1/4 - 20 thread the bolt
should be: 0.250 - (0.216/20) which equals 0.239.

Bob Swinney
"jim rozen" wrote in message
...
In article , Dan Caster
says...

If the top of the thread is slightly truncated because the diameter is
a little less than the nominal diameter, the strength is almost the
same and the effort to cut the threads is greatly reduced. The
Machinery Handbook has tables with dimensions for various classes of
threads.

Another point is, it's a lot easier to avoid drunken
threads from a die, if the stock is turned way undersized
for a length equal to about one diameter or so. This
allows the die to start cutting true, and in most cases
the first bit of undersized stock can be trimmed off
afterwards.

This is especially helpful with large diameter or
coarse threads.

Jim

==================================================
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
==================================================

In article , Robin S. says...

And if you're wondering how to find out them wee diameters with numbered
machine screws, a number 0 is .060" diameter, and every number is .013"
more.

Does that mean a 00 is 0.06060, and a 000 would
be 0.0606060?



Jim

==================================================
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
==================================================

jim rozen wrote:

Does that mean a 00 is 0.06060, and a 000 would
be 0.0606060?

Nope. Consider 00 as -1 and 000 as -2.
rant
It never ceases to amaze me how frightened a lot of people are of
negative numbers. My youngest son's grade 6 teacher thought numbers
less than zero were "imposible". The UTM coordinate system, while much
more convenient for most things than Lat/Lon, puts a false reference of
500,000 in the middle of a zone to avoid dealing with minus signs.
Accountants somehow figure placing a number in parentheses makes it
easier to understand than preceding it with a minus sign. Bah!!
/rant

Ted

"Ted Edwards" wrote in message
...

Accountants somehow figure placing a number in parentheses makes it
easier to understand than preceding it with a minus sign. Bah!!
/rant


According to my late father, (an accountant) this was much easer to spot on
a ledger page than a minus sign.

--
Roger Shoaf
If you are not part of the solution, you are not dissolved in the solvent.

In article , Roger Shoaf says...

According to my late father, (an accountant) this was much easer to spot on
a ledger page than a minus sign.

Red ink?

Jim

==================================================
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
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