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Help, brain fade question.

PostPosted: Sat Jun 13, 2020 11:31 am
by HJF
Which way does this undo please? Thread on the bit with the “wings” is left hand so I am thinking anti-clockwise?

Re: Help, brain fade question.

PostPosted: Sat Jun 13, 2020 11:47 am
by nmauduit
The photo is taken from a bit far to see for sure the thread direction... this looks like a radiator purge, the wing nut to operate it and a half thickness counter nut : I hardly see why this would need to be left hand thread, but if it is it would undo the opposite of regular nuts (and most likely the tap as well). Probably all somewhat stuck in the paint...

Re: Help, brain fade question.

PostPosted: Sat Jun 13, 2020 11:58 am
by Foxie
HJF wrote:Which way does this undo please? Thread on the bit with the “wings” is left hand so I am thinking anti-clockwise?


Yes, "brain fade" is appropriate here !

So i just went out and checked my original rad in the garage.

It's a left-hand thread, and the 'open' position is by rotating anti-clockwise.

;)

Re: Help, brain fade question.

PostPosted: Sat Jun 13, 2020 12:08 pm
by nmauduit
Foxie wrote:It's a left-hand thread, and the 'open' position is by rotating anti-clockwise.


interesting - any idea why it is left hand threaded? sounds like a recipe to overtighten it if not careful when purging in a rush or by a unknowing service man...

anyway I whish I had a tap on my radiator...

Re: Help, brain fade question.

PostPosted: Sat Jun 13, 2020 1:05 pm
by HJF
Okay Chaps, you gave me courage in my conviction and I went for it. It is a left handed so to open screw IN by going anti-clockwise and to close screw OUT by going clockwise. As it goes out it obviously causes the seat face inside to close. My view on why left handed is when tightening up to close you will automatically apply a clockwise tightening force on the nut that retains the complete tap assembly to the radiator so you don’t end up with the whole lot loose or worse, on the floor!
Thanks yet again for your support!
Harry

Re: Help, brain fade question.

PostPosted: Sat Jun 13, 2020 1:16 pm
by nmauduit
HJF wrote:As it goes out it obviously causes the seat face inside to close. My view on why left handed is when tightening up to close you will automatically apply a clockwise tightening force on the nut that retains the complete tap assembly to the radiator so you don’t end up with the whole lot loose or worse, on the floor!

thank you for the info, I'll try to remember it (at least for a while...), thinking of it as LH thread makes it behave like a regular bolt - or tap (unlike a brake purge that is)...