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smiife
9th January 2016, 04:53 PM
Hi guys,
Can anyone tell me what causes drunken threads?
I have threaded a hollow form and was making a top
with threads to match the bottom but when they screw
together it seemes to be uneven, which i think is called
drunken thread ..........and i have not had a beer yet!
Do i scrap both threads ? or can I find out which one
is wrong ?.............. OH WELL ,,,, I NEED A BEER NOW,,!:C

dai sensei
9th January 2016, 07:27 PM
You need a relief, ie no thread bit, on the lid between the thread and the top. See my note on your photo and one of my ball boxes

powderpost
9th January 2016, 10:45 PM
Hi Smiife,

Drunk threads can be caused by hesitating when striking the thread, and/or moving the chaser a tad too slow or too fast for that lathe speed. I have found that a speed of 350 rpm good for me. Try varying the speed a little and see if that helps. Often, just the fear of stuffing up a job affects your confidence.

My advise is to get a piece of 50 x 50 and chase a thread, cut it off and do it again and again and again, until you have convinced yourself that you have it all by the throat.


Jim

smiife
10th January 2016, 07:46 PM
QUOTE=dai senseI;921500]You need a relief, ie no thread bit, on the lid between the thread and the top. See my note on your photo and one of my ball boxes[/QUOTE]

Hi neil,
I tried what you suggested and it did line up better, then
I thought I would just tidy up the two faces and the thread
dropped through In to the hollow form and just spun around
It hasn, t been a good day:doh:


Hi Smiife,

Drunk threads can be caused by hesitating when striking the thread, and/or moving the chaser a tad too slow or too fast for that lathe speed. I have found that a speed of 350 rpm good for me. Try varying the speed a little and see if that helps. Often, just the fear of stuffing up a job affects your confidence.

My advise is to get a piece of 50 x 50 and chase a thread, cut it off and do it again and again and again, until you have convinced yourself that you have it all by the throat.


Jim

Hi jim,
I had another look at the base this morning,
I put a round bar in the hole of the female thread
and turn the lathe on slow , and It seemed oval ?
Eg..only touching every turn and missing some of the time !
So i started from scratch new insert and new top...male thread
was perfect .. female thread too big ! ........ glue up new blocks
start again......it ain, t been very sucessfull.....will try again tomorrow:~
Thanks for your help , as always appreciated:2tsup: