Threading
#1
This may be something that everyone already does but just in case ...

When cutting threads in a lathe, rather than using a thread micrometer I sometimes just check the fit with a nut from the hardware store.  A couple of them are stored in the same place as the taps/dies of the same thread dimension/classification/pitch.

This is normally adequate for class 2A threads (most common type) when you feel just slight movement between the nut and the threaded part.  If a rare requirement for 3A threads, with tighter tolerances, arises, the thread dimensions should be checked with the thread mike.

   

P.S.  I HATE measuring (or trying to measure) thread pitch using thread wires.  You need four hands most of the time, despite all of the weird suggestions (modeling clay, masking tape, styrofoam, etc) from experts.

   
Reply
Thanks given by:
#2
Randy,

remember nothing holds like a good cross thread.......
jack
Reply
Thanks given by:
#3
(08-13-2017, 09:14 PM)the penguin Wrote: Randy,

remember nothing holds like a good cross thread.......

Rotfl
Reply
Thanks given by:
#4
Those aren't nuts. They are poor man's thread gauges. :)
[Image: TomsTechLogo-Profile.png]
Reply
Thanks given by:
#5
(08-14-2017, 04:45 PM)TomG Wrote: Those aren't nuts. They are poor man's thread gauges. :)

Tom, after reading your comment, I had a thought:  could sawing through one side of a nut, cleaning up the threads and squeezing the nut in a vise - by trial and error - make a poor man's "no-go" gauge  ?  (Similar to adjusting a split die to fine tune thread dimensions.)  

Hmmmm, the problem would be calibrating that nut "gauge" 17428 without a male standard.  Oops.
Reply
Thanks given by:
#6
Make the male standard, measuring it with thread wires.
Free advice is worth exactly what you payed for it.
Greg
Reply
Thanks given by:
#7
(08-14-2017, 07:47 PM)f350ca Wrote: Make the male standard, measuring it with thread wires.

That's what I do to cut a female thread to size. Even if I don't need the male part, it's pretty quick to do and guarantees a female thread that is the correct size.

Tom
[Image: TomsTechLogo-Profile.png]
Reply
Thanks given by:




Users browsing this thread: 3 Guest(s)