rod size to thread size chart

[irishwoodsman]

HI

I normaly measure a bolt of the same size and turn the bar to that size .
If you want the tapping size for a hole, and you dont have the charts to hand ,find a drill that fits the inside of a nut of the size you want
I know this advice is crude, but when needs must, it works.

Regards BRIAN.

thats a great idea too ty for the info:biggrin:

 

[Tony Wells]

ty tony understand, you cant take a 1/4 inch rod and thread it for a 1/4 nut cause the rod is just a tad to big so you turn it down to the minimal or highest:biggrin:

Actually, for all practical purposes you can. The specifics for a 2A 1/4-20:


Size Class Basic High Low

1/4-20.

2A

0.2500

0.2489

0.2408

By the time you cut the thread, and deburr it, it will be under the high.

 

[irishwoodsman]

Actually, for all practical purposes you can. The specifics for a 2A 1/4-20:


Size Class Basic High Low

1/4-20.

2A

0.2500

0.2489

0.2408

By the time you cut the thread, and deburr it, it will be under the high.

ah ok darn thought i was gaining some ground lol but i understand:biggrin:

 

[irishwoodsman]

got me a chart to hang in garage now:biggrin:

 

[Pmedic828]

I Have a few charts that were developed on Excel. If you send me an email and put " need threading charts" in the subject line, I will attempt to attach these and send them to you. You can look over them and see if you can use them. Remember the subject line as I don't open emails from someone I don't know! Hope this helps. Anyone else, send me and I will return the charts!:allgood:

 

[ridgeway]

I use this thread calculator all the time...

http://theoreticalmachinist.com/Threads_UnifiedImperial.aspx

 

[rangerman]

so in laymen's term, you can put any thread on a piece of bar but if that bar is not turned down to the proper size the nut is not going to fit

Conversely, you can put any thread on a piece of round bar and if the nut is also threaded to match the same thread and dimension the two pieces would be perfect fit.

A threaded rod do not have to follow standard publish conventions as long as you can also make a nut or threaded hole exactly matched for it.

For example, if you really want to, you can have a threaded rod 11/16" - 21tpi and it would match a nut that is also threaded 11/16" - 21tpi.


OT
A long time ago before standards were established it was a common practice for manufacturers to make parts with proprietary dimensions.
It's still practiced to some extent by some manufacturers to this day to prevent others from repairing their products using standard parts that are easily available outside the brand.
The theory is to retain and hook previous buyers to keep on buying and supporting the same brand.
It's a sort of vendor/brand-customer hostage situation by design.