Author Topic: "Senior moment"  (Read 2008 times)

Offline scc

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"Senior moment"
« on: April 13, 2017, 08:42:23 PM »
Started on the water pick-up casting for my Burrell.  Set up in 4jaw, do all internal stuff,  get out "Zeus" thread book and check o/d for 3/4 bsp, machine casting to 1.041 in. Go for dinner...return to shop and check book for TPI and set up change wheels to suit. Cut good thread then notice my 3/4 bsp tap for the nut is 14tpi :noidea: I have just cut 10tpi on the casting having read for 3/4bsw on the adjacent page :facepalm:   What a good job I have to make the nut as well,,,,,no one will ever notice :naughty:

         You all have a good Easter                      Terry

Offline crueby

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Re: "Senior moment"
« Reply #1 on: April 13, 2017, 09:15:07 PM »
It's always satisfying to make something precisely, perfectly wrong!

Offline gerritv

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Re: "Senior moment"
« Reply #2 on: April 13, 2017, 10:04:41 PM »
Yet another advantage to single point threading, made to fit :-)

I recently cut several 1/2-40 and 5/16-40 ME internal and external threads, all at 60 because I only realized later on it was supposed to be 55. Fit great of course.

gerrit
Don't confuse activity with progress

Online b.lindsey

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Re: "Senior moment"
« Reply #3 on: April 13, 2017, 10:42:58 PM »
Easter Bunny poop happens. At least you can recover from it though. My last faux pas was unrecoverable.

Bill

Offline PJPickard

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Re: "Senior moment"
« Reply #4 on: April 14, 2017, 01:52:29 AM »
Since I teach a lot of engineering students...many learn the "making something perfectly wrong" thing the hard way. We all did(do) ;)

Offline Art K

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Re: "Senior moment"
« Reply #5 on: April 14, 2017, 03:55:28 AM »
Terry,
You didn't have anything more important to do anyways, right? :mischief: And you've always wanted to do an internal thread. I recall that in tech school I had to make an acme bolt and then the nut to fit it. Still have it laying around.
Art
"The beautiful thing about learning is that no one can take it away from you" B.B. King

Offline derekwarner_decoy

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Re: "Senior moment"
« Reply #6 on: April 14, 2017, 04:29:24 AM »
Yes Art K...even in Australia...the same test in 3rd year mechanical trade apprentices  :smokin2: in the early 70's

The thread form was ACME....to represent a bench vice screw......about 1" diameter....Steel Grade not remembered   :facepalm:

The nut was an irregular rectangular casting of good quality Cast Iron

An amusing check was the angular displacement [wobble] of the nut on the threaded shaft..... :lolb:

Derek
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Offline mikemill

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Re: "Senior moment"
« Reply #7 on: April 14, 2017, 09:42:35 AM »
The sign of a good engineer is  knowing how to get out of a cock up so no one will ever know!!! We have all been there.

Mike