Ss Fitting Thread Problem

[Sully]

Hi Guys,

I am putting together the kettle, tun & hlt and using a 1/2 SS parallel thread through the wall. I am having trouble getting some of the nuts and sockets on the thread, it screws partly on then gets really tight. the thread screws into the ball valve and t pieces no problem. It is on only some of the nuts and sockets.

Any ideas, its driving me nuts.

Cheers

Sully

 

[raven19]

Sully,

Is the thread damaged where the nuts are sticking?

My only suggestions would be some light oil to help lubricate while turning the nuts.

With the T-piece screwed onto one end, can you use this as a 'hold point', whilst using a spanner to get the nuts on?

Also - can you turn the nuts all the way on from one end to the other?

2c - hope this is of some use.

 

[jonocarroll]

Are you using plumber's silicone tape? Makes a world of difference.

 

[Sully]

Is the thread damaged where the nuts are sticking?

That was the first thing I checked and there doesnt seem to be any damage in either nuts, sockets or thread. Also cleaned the threads in case there was any swarf caught in there.


My only suggestions would be some light oil to help lubricate while turning the nuts.

Was concidering that but was a bit unsure on what to use as I dont want to leave any residual.


With the T-piece screwed onto one end, can you use this as a 'hold point', whilst using a spanner to get the nuts on?

Just gave it a go on your suggestion and it sticks too tight to grip and I dont have a fixed vice atm.


Also - can you turn the nuts all the way on from one end to the other?

The ones that do thread on go all the way.


Cheers

Sully

 

[Sully]

Are you using plumber's silicone tape? Makes a world of difference.

Yep, but only on the thread on the outside. Made no difference on the nuts and sockets though, I just tried that.

Cheers

Sully

 

[afromaiko]

Are the threads the same pitch? Sure none of it is actually tapered?

Edid: try putting them on a piece of brass threaded rod instead and see what happens. It will chew the brass before it damages the SS fittings/nuts.

 

[Kenny the plumber]

yeh sounds to me like the two have different threads? Mayby one is metric one imperial or one of half a dozen other threads?

 

[Sully]

Are the threads the same pitch? Sure none of it is actually tapered?

Edid: try putting them on a piece of brass threaded rod instead and see what happens. It will chew the brass before it damages the SS fittings/nuts.

I had to get a couple of the fittings from different suppliers, so I am wondering if that is the case. different supplier - different manufacturer - different pitch?

They arent tapered.


I will take the parallel thread down tomorrow and try different nuts and sockets.

Cheers

Sully

 

[raven19]

Boiling water will help remove the oil.

Now thinking about it a bit more - can you heat up the nuts in boiling water, then quickly turn them on. (Here is hoping heating the nut expands it to get it onto the thread easily)

Of course if this works it will be a bugger to ever get it back off...

 

[Sully]

yeh sounds to me like the two have different threads? Mayby one is metric one imperial or one of half a dozen other threads?

Definately 1/2" and pitch should be BSP/BSPP

The 2 sockets dont thread on at all - might be NTP

The 4 nuts - 2 pairs from different suppliers - one out of one pair threads on fine all the way, the other gets on half way on the nut. The other pair from the other supplier only thread on part way also.

But anyways, Ive cracked the shits with it and will get another couple tomorrow, but will take the thread to make sure. My hands are busted up enough.

Cheers Guys for the help.

Sully

 

[TidalPete]

But anyways, Ive cracked the shits with it and will get another couple tomorrow, but will take the thread to make sure. My hands are busted up enough.

Sully,

Probably a little late to give advice but it really sounds like some of your nuts & sockets may be well metric instead of 1\2" BSP.
It's a always good idea to take a sample down to wherever you are buying any bits & pieces of threaded gear from to be certain.
If you have a mate who has 1\2" BSP taps & dies you can fix the problem in a few minutes?

TP :beer:

 

[Sully]

Sully,

Probably a little late to give advice but it really sounds like some of your nuts & sockets may be well metric instead of 1\2" BSP.
It's a always good idea to take a sample down to wherever you are buying any bits & pieces of threaded gear from to be certain.
If you have a mate who has 1\2" BSP taps & dies you can fix the problem in a few minutes?

TP :beer:

If they are metric, they fuctup at the factoy as they are all stamped 1/2"-316.


Thanks anyways Pete.

Cheers

Sully

 

[Sully]

Well, to close this case and give the heads up for others to save heartache, I went to get new sockets and nuts and took the allthread down with me to make sure that they threaded. I went through the suppliers stocks and he had 3 different lots from 3 different manufacturers and only one lot fitted. He found it bizzare that I had that trouble.

Moral of the story is double check that all the fittings work before leaving the shop

Cheers for everyones input.

Sully