stock size for 4-40 thread

[seal killer]

Mauro--

Thank you! I'll look for a source. That is a good solution for me.

--Bill

[tornitore45]

Shipping may be more than the item.
Small Parts via Amazon
Mc Master
Enco
But best would be your local fastener store or hobby shop if you have one around.

[duckman903]

To clear up some of the corn fusion number sizes start at .060" each number going up adds .013" so a 10 thread is .013 X 10 = .130 + .060 = .190 and the same going down just subtract.

[mklotz]

Yes, as mentioned above, the equation is:

Major Diameter = .013*N + 0.060

where N is the screw number.

but, in the perfect idiocy of Inferial nomenclature systems, we have screws of size 00-90, 000-120 and 0000-160. The formula still works but you have to remember that 00 corresponds to N = -1, 000 to N = -2 and 0000 to N=-3. Couldn't ask for anything simpler than that, could you?

Sensible people use the metric system and create rational nomenclature systems that label threads by their major diameter and pitch and drills by their size instead of abstract numbers, letters, and fractions.

[earlgo]

My favorite part of metric threads is that one subtracts the thread pitch number from the major diameter to get the tap drill size.
Try that with UNC or UNF threads.

--earlgo

[GlennW]

Couldn't ask for anything simpler than that, could you?

Try working with BA threads!

They make machine screws seem quite rational.

[mklotz]

My favorite part of metric threads is that one subtracts the thread pitch number from the major diameter to get the tap drill size.
Try that with UNC or UNF threads.

--earlgo

Works just as well. Example tap drill for 1/4-20 thread...

Tap drill = 0.25 - 1/20 = 0.20

Closest drill to 0.2 is a #7 which is exactly what is usually used as a tap drill for this thread. Now, if we didn't use arbitrary numbers or letters to designate drills but rather "named" them by their size, things would be much easier.

In fact, the formula will work with any 60 degree thread form.

[earlgo]

Marv: Never occurred to me to try the calculation. Too easy to haul out the charts, I guess.
Thanks.

--earlgo

[ctwo]

This whole thread is like deja vu to me, right down to the distracting bug.

[seal killer]

ctwo--

This whole thread is like deja vu to me, right down to the distracting bug.

Ok. You caught me. That's why I started this thread. I didn't REALLY need to know stock size for 4-40 thread. I was BORN knowing such things.

--seal killer

[warmstrong1955]

This whole thread is like deja vu to me, right down to the distracting bug.

Not quite.....it's more like vu jade.

Deja vu....is that simple feeling, that you've been here before.....
Vu jade....is that feeling you've been here before, but you really didn't wanna go back.

Nuke the bug!

[JackF]

Harold, thanks for another "tip".

I too was confused, I didn't realize * ment "times".

Jack.