Question regarding ptfe tape

[jam]

Hello, what is the correct way to to wrap ptfe around a threaded male fitting, in some plumbing books it says clockwise and others it says anti-clockwise.Also how many wraps of ptfe are needed around the fitting that goes into the bottom of the radiator ,the tool used for the fitting is called a tail radiator key.I was told 12 wraps of ptfe around the the fitting,is this too many?
thanks

 

[kevplumb]

clockwise or it screws off when you tighten the tail

I use 10/12 wraps on a taper ie start at the end of the thread that goes into the fitting and work back

 

[namsag]

Hold fitting in left hand and wrap clockwise and start at the end of the thread by your hand finishing at the end that goes into fitting . As for the amount of tape used depends on wether you use the thin stuff or the thicker one wrap type.

 

[Diyisfun]

As Namsag say's, as for no. of turns, I was told many, many years ago by a very experenced works fitter 3 turns, I always use that no. of turns & infact have just fitted all new plumbing for sink, dishwasher & w/m without one weeping joint.

 

[jam]

Hello again, still a bit confused kevplumb says at the start of fitting from right to left,and namsag says from left to right of fitting or is it irrelevant.
Thanks again guys

 

[ChrisR]

Most piccies show working towards the end of the fitting. Easier if youhold the roll such that it does NOT unwind as you move it round the fitting.
Some rad valves would go right into the rad with only 3 turns. Some need 30 turns!
Tape is more likely to stay put if you "form" the thread with your thumbnail - just push in and run it round.

I've found the thicker tape (meant for gas) gives leaks with water, especially if the joint is moved after it's been done up.

 

[masona]

I remembered when I did my first year plumbing, my teacher always said the tape should be 1 1/2 times it thickness. Is this true, don't seem to be enough to me.

 

[ChrisR]

eh? Wots 1 1/2 times wot?

 

[masona]

Didn't explained properly, 1 1/2 time round ( 1 full circle and a half )

 

[jam]

Do you tear off the tape at the end of the fitting each time and start again or do you continue to go backwards clockwise for the amount of turns needed.
Thanks.

 

[kevplumb]

continuosly
its all a matter of what you get used to i do it my way it works somebody else another way it works for them

when i learned it was hemp and paste ahhh lhe old days,hands raw and stinking of boss white

do it as you feel comortable ,we all have to learn