Imperial or metric!

[mack22]

Can anyone please advise the O/D of the old imperial 3/4'' and 1/2'' copper pipes in metric, as my callipers are metric... I have to re route some pipes and need to be prepared with the right fittings (for a change) before I start..
Thank you

 

[gaspastemania]

just get imperial/metric fittings,
what work are you doinfg?

 

[GasmanxxxR1]

As gapastemania says you can get copper metric to imperial adaptors that solder on in the same way as all end feed fittings

 

[HTBA]

I've always found 15mm metric and 1/2" imperial copper to be about the same external diameter, the imperial maybe a shade bigger so I use compression fittings.

If you're using soldered fittings on the 22mm metric to 3/4" imperial you can get either end feed or solder ring metric to imperial straight couplings. If you're using compression fittings on these sizes you can get imperial olives and just replace the metric ones that come in the fitting.

 

[diamondgas]

mack22 :welcome: You can also get compression olives I believe ..... If it's any help the 3/4" were deffo smaller and i think the 1/2" were a tad larger ... been a while since i came across them to be honest... 🙂

 

[gaspastemania]

why not go with whatever woirks fitting wise?

 

[PlumbBobBob]

you can get 15mm to 1/2" and 22mm to 3/4" end feed straight couplings quite readily from toolstation, and 3/4" olives available online from ebay where i got mine. also bes do the complete range of fittings. oh and welcome to the forums.

 

[steadyon]

For what its worth:

1/2" imperial pipe is 15.138 mm outside diameter
3/4" imperial pipe is 21.488 mm
1" imperial pipe is 28.245 mm

The above is based on standard pipe sizes from BS659 (1944).

 

[mack22]

Thank you steadyon, and everyone else, I checked sizes and found a bit of a mixture, at least I am prepared, and just doing a job list for parts, its amazing how the price of solder flux has gone up!

 

[GasmanxxxR1]

I like Everflux meself

 

[mack22]

What about Screwfix own brand flux, is there really a lot of difference between them!

 

[dontknowitall]

For what its worth:

1/2" imperial pipe is 15.138 mm outside diameter
3/4" imperial pipe is 21.488 mm
1" imperial pipe is 28.245 mm

The above is based on standard pipe sizes from BS659 (1944).

I thought this was a plumbers forum, not an engineers ...

Cheeky dkia

Thanks for those! You never know when that might be useful to know but I bet in a few weeks I'll be wondering which thread it was!!

 

[Bernie2]

Funnily enough before we went metric copper was usually say 1/2" and its walls where pretty thick. But I am getting on a bit now, but remember what we called screwing gauge copper which was a size on its own. I can't remember what o/d size it was but it was really thick, if you come up against it at any time. And you could of course cut a thread on it with a set of stocks and dies.

 

[Hump1]

If you want to form bends on 1/2 inch copper 15mm spring is no good. 1/2 inch copper bore to small as I found out. Fill 1/2 inch copper with dry sand and heat to bend, dosn't flatten copper.

 

[stevetheplumber]

youll have no problems with the 15 mm fittings but the 22 will be too loose you need convertors you cant put 22 into a 3/4 compresion fitting but you can the other way round with a thick ring

 

[tamz]

If you want to form bends on 1/2 inch copper 15mm spring is no good. 1/2 inch copper bore to small as I found out. Fill 1/2 inch copper with dry sand and heat to bend, dosn't flatten copper.

Are you being serious here.
You would strip it out, (impossible to do insitu) fill it with sand, and refit it just to get a bend on it? Well you learn something new every day!
The things some people will do to spin a job out :lol:

 

[AWheating]

you may sometimes come across 1/2 copper that you cant get a 15mm fitting on unless you file it down quite alot, in which case a 1/2" to 15mm can help you out. I worked on one housing estate years back that had alot of very thick 1/2 copper installed, we managed to get some 16mm to 15mm compression couplers from travis perkins of all places.

 

[Hump1]

You got up to all sorts of tricks 45+ years ago like playing with lead pipes, forming lead joints with moleskins and tallow!!

 

[Bernie2]

Yes the screwing gauge copper was a nuisance in some ways, except when taking it for scrap. We used barrel connectors cutting a thread on the end of the pipe with small stocks and dies. I suppose you can still see it sometimes on old gas piping as well as water. But as somebody said trying to get a compression, end feed or solder ring fitting on to connect up to new pipework was a long boring job.

The problem being filing the wall down even all round the pipe. Easy enough if the pipe is on a work bench, but not perhaps so easy if it is dangling 10 feet up in th air off Munson rings and shaking about when you touch it or vibrating like mad when you try to file it. r the odd little job I can manage.

 

[Bernie2]

Sand filling 15mm?

Oh! Come on your having a laugh!!🙂

Incidentally although sand bending is a well known way to bend pipe, they also sell a hot melt stuff that does the same thing. Its some kind of metal as far as I know, with a low melting point. I think you just anneal the copper over the bend area, let it cool, then melt the stuff after blocking up the end of the pipe, pour it in, it sets and then you bend the pipe, then you heat the pipe and it runs out.

The problem with sand bending is drying the sand then packing it tight enough to bend the pipe. It is usually far to fiddly in the work time allowed. Although sometimes perhaps you have no alternative but to do it this way. You can also bend 4" (100mm) plastic with sand the same way.

 

[mack22]

Having posted the original question, I have learnt a lot more besides, the sand bending being one, a real education into the bygone days of plumbing ( or perhaps not so bygone in some properties north of Watford !!)

 

[Hump1]

I remember way back in the 60's having to bend 1.1/2 copper ( or it might have been 2 inch ) copper with the sand method as we didn't have a spring that big. It was a case of pariffin blowlamps on the sand filled copper and a conglomeration of wooden planks and logs to form it round all done outside of course. We found it easier to bend still redhot then cool it. There wasn't much H/S around then. I also remember the thick screwed copper you mentioned, came across it in hotel kitchen appliances and whisky distilleries often polished up rather than hidden away. Also worked with a lot of lead and asbestos but I am still here at 67 and in good health!

 

[Hump1]

Never tried the sand bending on 100mm plastic. I presume you dont heat it with gas torches!!

 

[Bernie2]

Yes! I think it was Marley published a way to do it which is basically the same as sand bending copper but you heat the sand rather than the pipe. I found it even more fiddly than sand bending copper. Anyway bends were and are a lot cheaper. But building officers do not like bends on the live side of a vertical soil stack, its okay on the vent side but not the live side. So it may come in handy to know that you can do it, if the stack position does not align up with the underground drain position.

 

[GQuigley67]

when I have not had any imperial olives, i just use alot of ptfe around the olive and alot of paste, works so far.