Cross threading nylon thread

[billybob150811]

while cutting the end of a ball valve i woundered if anyone on here had a great way of fixing cross threaded threads

 

[gasmanrob]

i use a male iron and wind it on a bit then off then on a bit more then off takes a while but gets there in the end use the same on brass and iron too.

 

[Guest123]

Cut off the damaged section of threaded tail and use a female coupling instead.

Like this:Female Coupler 15mm x ½" | NoLinkingToThis
Also available in chrome.

 

[Carl86]

Different to this situation but can still cause similar problems..

Another tip, I find it easier on CC WC cisterns to couple an isolation nut on to the inlet valve before the cistern is secured and in a fixed position then you can gauge when the nut is niping up into an akward position or if its niped up square to the inlet for a good seal.

if its a pushfit JG iso valve or a regular valve and the water to the house will be isolated for other reasons i find it easier to leave the isolation valve tight on the cistern and the pushfit/compression nut loosed off the pipe.

 

[Guest123]

Was installing a shower this morning and teed off the rising main in the attic. Was going to run it in a plastic coil, down from the attic, then through a cavity wall to the bathroom ,when I noticed shredded material under the tank, a tell tale sign of mice, so it was done in copper as I don't like taking chances with plastic and pesky wee mice.

 

[lewisplumber]

Try PTFE to pack it out. Or if it is a toilet inlet cut it off square and file it flush and it will be good as new. And if your joining on with. Flexi you won't have to do any pipe work adjustment.!

 

[Hybrid]

And if your joining on with. Flexi you won't have to do any pipe work adjustment.!

The sight of a flexi on a cistern inlet fills me with inexplicable rage.

 

[lewisplumber]

Just covering all peoples aspects of plumbing!

 

[Best]

Throw the valve away & fit a Fluidmaster Pro or other valve with brass tail.

 

[SimonG]

If it cross threads its out with the grinder and straighten it off.

 

[tamz]

If you have to cut the tail of a ball valve leave the jamb nut on when you cut it then wind the nut back and forth over the cut edge. That will line the threads up.
To join back on to it without faffing about wasting time getting a flat edge, leave a jamb nut on it and use a female adaptor and seal it with the jamb nut like a long screw.

 

[Guest123]

Yes, Female adaptor and Jamb nut, that's what I do, doesn't leak, or if it's a chrome Female Adaptor, wind some PTFE round the threads of the ball valve and it will seal no problem.

 

[WaterTight]

If you have to cut the tail of a ball valve leave the jamb nut on when you cut it then wind the nut back and forth over the cut edge. That will line the threads up.
To join back on to it without faffing about wasting time getting a flat edge, leave a jamb nut on it and use a female adaptor and seal it with the jamb nut like a long screw.

sounds good. no idea what you're talking about but sounds good.

 

[WaterTight]

ah hold on. is the jamb nut the ball-valve nut on the outside of the cistern?

 

[Guest123]

ah hold on. is the jamb nut the ball-valve nut on the outside of the cistern?

Yes, but use an extra jamb nut/back nut on top of the female adaptor to seal it.

 

[WaterTight]

wall?

 

[WaterTight]

are you two talking scottish again?

 

[galaxy_plumbing]

they are, indeed...

 

[Guest123]

EDIT, Wall = Back nut. Sorry pal, doing quotes and my brain is fried.

 

[tamz]

This is a long screw joint


The thread to the left is a parallel thread, around 2" long. The thread on the right is a standard taper. They are used to insert a piece of iron pipe or tee into a section instead of using split unions.
To make the joint you wind the jamb nut and union fully on to the long thread. Insert your piece of pipe the exact length so the threads but up (or near enough) with the ends taped or pasted. Wind the union off the long thread onto the short one and tighten it. Tape or hemp and paste behind the union (like a washer) and tighten the jamb nut fully against it.

Same principle with a cut ballcock thread. Wind on a jamb nut, and female adaptor, tape around the top of the female and tighten the jamb nut down on it.
It won't leak.

 

[Guest123]

Very artistic Tam, you been on a fast track design course? :biggrin:

 

[tamz]

Nah i googled it. Took me 10 minutes to find it. i could have made one quicker :lol:

 

[stevetheplumber]

cut the damaged bit of as square as you can and use a brass tap extender you can get ones that are very short like this http://www.bes.co.uk/product/90~PL~1524~1524~-Tap-Extensions.html i use a green 15mm boiler washer inside and a bit of tape on the thread

 

[REDSAW]

sod that!. i will bang a new one in and bill it.lol.