|Lee Reynolds 1||29/07/2015 10:29:11|
|6 forum posts|
I have been asked to make an extension to a friend's snooker que.
One end requires a standard UNC thread, the other, this one.
The que, at this point, is a little over 1" dia., the thread measures 0.362" OD, 12 TPI sort of matches. maybe 13!
ACME threads of 3/8" dia are 10 TPI seemingly (not that I have had anything to do with this type of thread).
Any ideas anyone?
|Brian Wood||31/07/2015 10:15:15|
|2438 forum posts|
There have been discussions elsewhere on the forum in the past about using Delrin as Tee nut material to replace worn units.
It can be simply moulded around this stumpy thread as two halves which will heat bond on the edges to make a whole cylinder which you then machine and fit to the extension.
The only precaution you need to take is to make sure you don't extend the 'nut' into the thread run out area on the fixing side otherwise you will have some difficulty unscrewing it when cold. A spray of WD 40 on the thread should help as a mould release agent.
|Roderick Jenkins||31/07/2015 12:28:58|
2122 forum posts
From here, that looks as if it could be a square thread, even less chance of finding a suitable tap. Brian's suggestion is a good one, there's a link here to a description of the method.
Isn't it amazing how these little jobs for a mate turn into epics!
|Andrew Johnston||31/07/2015 12:37:27|
6235 forum posts
To answer one of the questions asked by the OP; the tpi for a given size of Acme thread can be whatever the designer chooses. There are recommendations, for 3/8" it is 12tpi, but the 'standards' are not hard and fast.
It's not difficult to make a set of taps, if I can do it I'm sure everybody else can, these are 1/2" diameter, 8tpi, square thread serial taps:
|Clive Foster||31/07/2015 13:10:12|
|2817 forum posts|
Looks like you can buy both screw and socket for £ very reasonable e.g. **LINK** . Dunno about you but the £4 including delivery quoted there doesn't buy the amount of futzing about in my shop that figuring out the thread and making a socket from scratch involves. If it is a different thread just change both ends. If you are buying in the wood there are specialist suppliers for that who may also do the joiners.
After too many "mates -rates" epics I've finally learned to start charging properly for hassle stuff that isn't an essential or emergency. Friend count is down but who needs folk who just want cheap shop & skills access. However personable.
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