What size rod do I use for 8-32 threads.I tried 3/16 but it is too big.
thanx

--Well a clearance drill is 11/32" so it's probably a little below
that. Look in the Handbook tho for the correct dia to turn that down to
before attempting to thread it..

--
"Steamboat Ed" Haas : A steaming pile of
Hacking the Trailing Edge! : obscure information...
www.nmpproducts.com
---Decks a-wash in a sea of words---

--Oops! Misspoke; not 11/32 but 11/64"!!

--
"Steamboat Ed" Haas : A steaming pile of
Hacking the Trailing Edge! : obscure information...
www.nmpproducts.com
---Decks a-wash in a sea of words---

Sofolatris wrote:
What size rod do I use for 8-32 threads.I tried 3/16 but it is too big.
thanx



The major diameter for #8 threads is .164"
#10 is .190"
Randy

On Aug 25, 2:55 pm, Randy Replogle wrote:
Sofolatris wrote:
What size rod do I use for 8-32 threads.I tried 3/16 but it is too big.
thanx

The major diameter for #8 threads is .164"
#10 is .190"
Randy

For home/hobby low-stress application, 5/32" dia. rod for #8 threads
would be OK.
For #10 threads 3/16" dia. rod is acceptable.
#5 thread is .125", ie. 1/8" diameter.

The rule for # thread outside dia. is quite simple: Begin with #0
thread which is .060" diameter. The steps between thread numbers are
a uniform .013".

For example consider #5 thread: .060 + (5 x .013) = .060 + .065 = .
125".
Another, say #10 thread: .060 + (10 x .013) = .060 + .130 = .190".

In fact the outside dia. of a screw thread can be considerably smaller
than the theoretical requirement. .005" undersize on smallish
screws, .010" on somewhat bigger, and .015 0n 1/4" dia. and up. A
quick review of the tolerance tables of screw threads in Machinerys
Handbook will disclose the standard tolerances. For home/hobby use
larger tolerances may be acceptable.

Trust this helps.

Wolfgang

On Sat, 25 Aug 2007 13:41:29 -0400, Sofolatris wrote:

What size rod do I use for 8-32 threads.I tried 3/16 but it is too big.
thanx



Outside diameter of 8-32 is 0.1640", so turn the 3/16" down a bit and you're
there.


Mark Rand
RTFM

According to Sofolatris :
What size rod do I use for 8-32 threads.I tried 3/16 but it is too big.

Well ... the simplest way to find out in your shop what size is
to look in a number size drill index, and see what the "body" drill is
for the thread in question, and turn the rod (in your lathe) a couple of
thousandths or so smaller.

In the case of 8-38 (Or other #8 threads) my "number-screw"
program says:

================================================== ====================
izalco:dnichols 18:26:43 number-screw 8 32
For a #8-32.000 screw:
Clearance diameter: 0.164
Tap drill diameter: 0.133
================================================== ====================

so I would turn to about 0.162" or perhaps 0.160".

I would also be more likely to use the lathe to do the
threading, as it is easier to get the threads straight and concentric.
You might use the die to finish up threads which are not quite deep
enough, as this will at least make it easier to start the die straight.

Good Luck,
DoN.
--
Email: | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

On Sat, 25 Aug 2007 18:55:56 GMT, Randy Replogle
wrote:

Sofolatris wrote:
What size rod do I use for 8-32 threads.I tried 3/16 but it is too big.
thanx



The major diameter for #8 threads is .164"
#10 is .190"
Randy

This may sound like nitpicking, but .164 is the *nominal* size of a #8
screw thread. The *major diameter* (the actual diameter at the thread
crests) is determined by applying an allowance to the nominal diameter
to insure interchangeability. Major diameter for a 2B thread is .1571
to .1631, which is the number the OP is looking for. As has been
mentioned, 5/32 is close enough, 4mm would fall in the spec.

--
Ned Simmons

Ned Simmons wrote:
On Sat, 25 Aug 2007 18:55:56 GMT, Randy Replogle
wrote:

Sofolatris wrote:
What size rod do I use for 8-32 threads.I tried 3/16 but it is too big.
thanx


The major diameter for #8 threads is .164"
#10 is .190"
Randy

This may sound like nitpicking, but .164 is the *nominal* size of a #8
screw thread. The *major diameter* (the actual diameter at the thread
crests) is determined by applying an allowance to the nominal diameter
to insure interchangeability. Major diameter for a 2B thread is .1571
to .1631, which is the number the OP is looking for. As has been
mentioned, 5/32 is close enough, 4mm would fall in the spec.


OK, if you want to pick nits........
This chart shows all of that
http://www.engineershandbook.com/Tab...readlimits.htm
Randy

On Sun, 26 Aug 2007 00:48:23 GMT, Randy Replogle
wrote:

OK, if you want to pick nits........

What's a few nits between friends? (Other than the origins of polite
society - you delouse me and I'll do the same for you.) g

This chart shows all of that
http://www.engineershandbook.com/Tab...readlimits.htm

Machinery's Handbook lays it out as well, complete with definitions,
pictures, and the logic behind it all.

--
Ned Simmons

"Ned Simmons" wrote in message
...
On Sun, 26 Aug 2007 00:48:23 GMT, Randy Replogle
wrote:

OK, if you want to pick nits........

What's a few nits between friends? (Other than the origins of polite
society - you delouse me and I'll do the same for you.) g

This chart shows all of that
http://www.engineershandbook.com/Tab...readlimits.htm

Machinery's Handbook lays it out as well, complete with definitions,
pictures, and the logic behind it all.

--
Ned Simmons

All this mental badminton and mental masturbation is fun, but it's hard to
beat a good book of facts.

Steve

SteveB wrote:


All this mental badminton and mental masturbation is fun, but it's hard to
beat a good book of facts.

Steve

What's your point?
Randy

I'm not one for memorizing things so what I do is merely pick up a 8/32
screw and measure it. Now you have the major diameter.


"Sofolatris" wrote in message
...
What size rod do I use for 8-32 threads.I tried 3/16 but it is too big.
thanx