On Sun, 10 May 2009 13:43:26 -0700 (PDT), jon_banquer
What type of thread gage?
Plug, ring, snap, ID or OD single element indicating, ID or OD
functional indicating, tri-roll, thread overlay, etc., etc., etc.....
Do you really not know the answer?
How would you check a pitch micrometer?
There is usually a product such as a set gage or master involved.
You don't unless you can check it yourself. Being given a
certification means next to nothing unless you purchase your gage from
a reputable gage manufacturer and there are a bunch of bad ones out
Thread ring and plug gages check very little, they check functionality
to mating part (sort of) but they can't tell you if a thread is good.
In some industries, some products using thread ring or plug gages may
be acceptable but in reality they only give an indication if thread is
good or not. For some industries and products they are near useless
especially for critical applications.
A big tip off is when you open a box of brand new gages, unpack them
and look only to find chatter all along the gage surfaces (threads).
Never would have thought of that.....LOL.
Machinery Handbook tells you how to inspect a thread and what methods
are acceptable in all situations, for all products, parts, industries,
employers & customers?
Finding a thread spec wasn't the point. I was talking thread
inspection, acceptable inspection methods which is an entirely
different matter than reading a thread spec or finding the size chart
and tolerance information on a print or in a book.
Used to be.....maybe till about the mid 80's IIRC.
How did you check threads, internal and/or external?
There are still people today that check an internal or external thread
with a pair of calipers, micrometer and a bolt, nut or mating part and
that's it. As Mr. Wuhl on HBO says, "I shit you not!"
If someone is using caliper to check minor diameter on internal thread
and OD micrometer to check major diameter on external along with go
ring or plug gage it's the same frickn' thing, neither method tells
you if you have a good thread...."I shit you not!".
I don't know why you are becoming aggressive. I am only trying to
understand what you wrote because your responses so far are not clear
Doesn't matter running class 1, 2 or 3 thread, all have the same
dimensions to be checked.
Are you a machinist? I ask because by your responses and questions so
far like this one here, make me wonder if you actually have any first
hand experience making or inspecting threads.
Direct answer to this question:
Doesn't matter how a thread is made, Thread Form, Dimensions,
Tolerances don't change due to method of manufacture. For instance if
the thread form calls for a .012" Rounded Root Radius, doesn't matter
how the thread was made or what type of machine was used, the threaded
part needs to have a rounded root radius within tolerance.
In my case having threaded millions of parts, frequency of inspection
during a run may vary due to method of manufacture. For instance I
will check Root Radius much more frequently on Cut Threads vs. Rolled
Yes, that is one thing to check but most people don't.
Answer a direct question with a direct answer. If you weren't evasive
and/or unclear in your responses we would be done by now.
Sure, again, that is obvious.
And depending upon the use, spinning a class 2 nut onto it may be all the
For instance, when was the last time you used a fishtail to grind a
high-speed steel threading tool?
I have a 55 degree fishtail for Whitworth threads that is older than I am,
and I have actually used it twice.
A class 2A thread callout on the print means "spinning a class 2 nut
onto it may be all the inspection needed" "depending upon the use".
OK, NOW I understand why you said "Threads are the simplest of our
trade." That is all I was trying to get to, now I understand how you
can make that statement.
I used to make my own single point threading tools. I would braze
carbide tip to HSS square shank, grind the included angle on pedestal
grinder check on comparator, if good with diamond file tool on
comparator put the radius on. Big deal, still has nothing absolutely
nothing to do with how a threaded part is inspected which is the
subject you keep trying to change.
Who cares? It has nothing to do with inspecting threads.
Then why are you having such difficulty clearly stating how YOU
The question wasn't what you "would" use, the question is how do/did
YOU check threads.
Which has absolutely NOTHING to do with what I wrote. Try to focus,
the issue is and has been inspecting a thread NOT making one.
I wrote: "Doesn't matter how a thread is made, Thread Form,
Dimensions, Tolerances don't change due to method of manufacture. For
instance if the thread form calls for a .012" Rounded Root Radius,
doesn't matter how the thread was made or what type of machine was
used, the threaded part needs to have a rounded root radius within
I am not the one with the difficulty.
Obviously, it depends upon the surface finish and tolerance call outs. Most
often I use three wires and a magnifier on an OD thread, or I use ThreadTech
to make a gage. Never had one rejected, and as I said before and again, it
aint rocket surgery.
Why are you making such a big deal out of nothing?
YOUR very first post in this thread;
"And if you cant handle simple math;"
"What color is your cape, Superman?
Came first, I responded in kind.
You most often check thread pitch diameter with wires on external
threads or you made a homemade go functional gage and use it. And
that's fine, in some places it's more than enough.
Asking how you check a thread wasn't a trick question.
I said OK, I now understand why you can say "Threads are the simplest
of our trade." That is all I was trying to find out and you finally
made it clear. By your description of how you normally check threads I
can now understand your statement that "Threads are the simplest of
If all anybody ever had to do was use thread wires on external threads
and sometimes use a go gage for ID or OD threads and not having to
inspect any of the other thread dimensions then yes, threading truly
is simple, easy even, lucky you.
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