Cast iron auto air vents

[JCplumb]

Hello gents,
Went to a job to replace a snapped off bleed fitting on a rad today expecting it to be a straight swap for a 1/2 inch one out of the toolbox and found this snapped off the 1 3/4" reverse thread bush from an old looking cast radiator.

I phoned every merchant in Bolton and got no joy and was looking at having to order one which would have taken a few days at least.
If you guys ever use these, where do you get them from?

Also why are they called 1/8" when the threaded diameter is about 10mm?

Incidentally after phoning Kev he came to my rescue with a similar item that had been rolling round the back of his van for a few weeks, that must be 2 pints I owe him now and a Biryani

 

[Ermintrude]

Graham's and crosslings keep them instock up here.

 

[Chalked]

Could you just replace it with a manual 1/8th air tap?

 

[JCplumb]

Graham's and crosslings keep them instock up here.

Grahams here didn't have them, they could order them in though.

Could you just replace it with a manual 1/8th air tap?

That's pretty much what I did (thanks again Kev), but not usually something I'd keep in stock.

 

[Chalked]

Most merchants keep the manual type.

 

[JCplumb]

Most merchants keep the manual type.

Not round here they don't.
PTS were funny, when I phoned them it was like I was asking them how to do brain surgery

 

[kris]

You can always use a standard 3/8 airvent and then use bushes as neccassary
Ex
3/8" -15mm then 15-22 brass bush or 1/8"-1/2" bush then 1/2" - 3/4" bush hay presto- Load o brass

 

[Chalked]

Even b&q keep them!
B&Q - Search
Shame they can't fit the bush the right way round!

 

[JCplumb]

Ermahgerd!
B and Poo do them? I drove past there twice on my way to poofix!

Well I must admit, I feel a little silly now...

 

[kris]

Soz JC ignore last part , just re read your thread,,,,- did any threads damage on the bushes in the rad as probably aswell taking bush out renewing bush aswell if damaged but im sure you can get a standard 3/8" vent then bush it up

 

[snowhead]

Also why are they called 1/8" when the threaded diameter is about 10mm?

Pipe size.

 

[kris]

Hay chalked ive gotta say your avatar is Brilliant , "you have each other " class

 

[kris]

Its not 1/8,, though its 3/8" 3/8" = 10mm i think, same as some gas fire fittings

 

[JCplumb]

Soz JC ignore last part , just re read your thread,,,,- did any threads damage on the bushes in the rad as probably aswell taking bush out renewing bush aswell if damaged but im sure you can get a standard 3/8" vent then bush it up

The threads were fine, the bush was about 1 3/4" and was reverse thread, is that common?

 

[Chalked]

The threads were fine, the bush was about 1 3/4" and was reverse thread, is that common?

Most cast rads are left hand thread one side and right hand on the other. It's so the jointing nipples between the sections tighten.

 

[JCplumb]

Its not 1/8,, though its 3/8" 3/8" = 10mm i think, same as some gas fire fittings

Yeah I did the maths myself so wondered why it was called a 1/8.
I was surprisingly unlazy just now and Googled it myself rather than expecting you guys to drip feed me the knowledge I want
Turns out the 1/8" is the internal bore of the threaded part. How stupid is that? I can see times when you might want to know the bore, but I want the fitting to fit in the hole I have first and worry about the bore later...

 

[kris]

I tell you another case have you ever fitted a mixer tap JT that comes with flexi connectors and you need a straight male to connect on only its way smaller than 15mm, Its a 3/8" straight male,, its the only time i have hassle tryin to explain in builders merchants what i want as they stock it but are hardly ever asked for it now, i wished they would just change it to metric,

 

[JCplumb]

It's late, I've had a few beers now and not sure if I get the last post. Do you mean like the Grohe tap connectors? They're a PITA, but fit nicely on a 15mm/10mm compression reducer.