Old plastic plumbing?

[Tracy D'arth]

Does anyone know about old 1/2" grey plastic plumbing from the early 1980s?  This stuff is put together with hex screw on nuts in an old David Piper boat.

Nothing current seems to fit it.

[Tony Brooks]

2 minutes ago, Tracy D'arth said:

Does anyone know about old 1/2" grey plastic plumbing from the early 1980s?  This stuff is put together with hex screw on nuts in an old David Piper boat.

Nothing current seems to fit it.

 

Has it only got about a 3/8" bore so very thick wall. If so our boat had it and I was advised that it was a very early speed fit design.

 

You are correct, it is a sod to join onto anything modern, however

 

In one case I had the nut and plastic olive stuck on the end of a pipe and I got a seal into an ordinary compression fitting, I think the thread in the nut is BSP. In another case I managed to get a compression olive and nut onto the pipe and again I got a seal, but I think it was belt and braces with PTFE tape or silicon. Both were probably best hidden from view.

[Tracy D'arth]

That sounds very much like the stuff.  I thought it would be a job and a half to join up to it so I will advise the guy that my initial idea to rip it all out from his water pump onwards would be the best.

Its a rats nest anyway.

[MtB]

6 hours ago, Tracy D'arth said:

Does anyone know about old 1/2" grey plastic plumbing from the early 1980s?  This stuff is put together with hex screw on nuts in an old David Piper boat.

Nothing current seems to fit it.

 

I remember a dark grey coloured plastic pipe system made by a firm in Windsor back in the 80s. Can't remember the name of the system but the nominally 1/2" pipe was 16mm external diameter and it was mainly a solvent-weld system. Sized to deliberately stop it being compatible with conventional copper sizes and systems. Latterly a fragile disaster area as it was not UV stabilised and became terribly prone to shattering if physically shocked or stressed, so always well worth totally replacing or refusing to get involved ("you touched it last" syndrome).

 

Speedfit (launched about the same time) OTOH was sized specifically to be compatible and has always been 15/22mm and latterly 8/10/15/22/28mm IIRC.   

[Ronaldo47]

You might get a 16mm compression fitting adaptor in France.   From memory, they have their own range of copper pipe  sizes: 12, 14, 16, 18, 22 mm o/d. When my late brother-in-law went to live in France, he took his yacht with him, and on a visit I had the devil of a job bodging something to replace a faulty  15mm pipe connector on his boat.  

Edited October 19, 2022 by Ronaldo47
typo

[Tracy D'arth]

It is 1/2" OD, 12.5mm.

[Eeyore]

7 hours ago, Tracy D'arth said:

It is 1/2" OD, 12.5mm.

At a pinch you could use a fat o ring and a washer instead of the olive in a 15mm compression fitting. The washer is to prevent the o ring squeezing out between the pipe and the nut.

Edited October 19, 2022 by Eeyore

[adrianh]

1/2 inch compression fittings are still made in brass for use in the truck industry ( air brake pipework) as well as other industrial systems. Google Wade or look at agricultural spares suppliers 

[Tracy D'arth]

18 minutes ago, adrianh said:

1/2 inch compression fittings are still made in brass for use in the truck industry ( air brake pipework) as well as other industrial systems. Google Wade or look at agricultural spares suppliers 

Wade have closed down unfortunately.  The problem is that there are no support sleeves for the inside and the plastic will creep and deform without  if a hard olive is used.

I am sure the best answer is to dump it all and replace with modern pipe  and push fit fittings, he will have more confidence in the plumbing then.

[MtB]

5 hours ago, Tracy D'arth said:

Wade have closed down unfortunately.  The problem is that there are no support sleeves for the inside and the plastic will creep and deform without  if a hard olive is used.

I am sure the best answer is to dump it all and replace with modern pipe  and push fit fittings, he will have more confidence in the plumbing then.

 

I agree. 

 

Fine to muck about with bodgery on one's own boat where if later it all turns to ratshit it is only one's one stoopid fault, but Tracey I suspect is doing this for a paying customer who will be expecting full recompense and correction should any adaptor later fail. The "you touched it last" syndrome I mentioned earlier. 

 

Sometimes, actually no quite often, it is better from a commercial point of view to swerve the jobs with potential to be grievous trouble later on, and leave them to other technicians with less foresight. Same applies to customers with the same potential. 

[Rose Narrowboats]

It's called Qest and often "mispelt" as Quest.

 

It's still available in the US. I don't know of a UK supplier, but it can be ordered via Amazon. Get a straight coupler (part number QAC43R), take the nut off one end and use the male thread to connect a 15mm fitting to.

 

The threads are 1/2" NPT rather than BSP, but that's never been an issue on Shurflos etc.

Edited October 20, 2022 by Rose Narrowboats

[Tracy D'arth]

30 minutes ago, Rose Narrowboats said:

It's called Qest and often "mispelt" as Quest.

 

It's still available in the US. I don't know of a UK supplier, but it can be ordered via Amazon. Get a straight coupler (part number QAC43R), take the nut off one end and use the male thread to connect a 15mm fitting to.

 

The threads are 1/2" NPT rather than BSP, but that's never been an issue on Shurflos etc.

Bingo! That's the stuff, thanks.  Sorted.  

Thanks to all for your input.

[Eeyore]

For our non technical readers

1/2" BSP and NPT is the only thread in those two ranges to have the same pitch/tpi. The difference in the thread angles, 55 and 60, respectively is fairly academic on moulded plastic threads. Nearly all plastic bodied water pumps are NPT, regardless of what the chandlers tell you; and easily accept 1/2" BSP fittings such as tap adaptors.

[Eeyore]

1 hour ago, Tracy D'arth said:

Bingo! That's the stuff, thanks.  Sorted.  

Thanks to all for your input.

There is an interesting note/warning at the top of this page https://keithspecialty.com/plum.Qest fittings.htm   This might suggest that the installation is nominally 3/8"?

Edited October 20, 2022 by Eeyore

[Tracy D'arth]

3 minutes ago, Eeyore said:

There is an interesting note/warning at the top of this page https://keithspecialty.com/plum.Qest fittings.htm

Warning about what?

[Eeyore]

2 minutes ago, Tracy D'arth said:

Warning about what?

That they use the id of the pipe to specify the size of the fitting, so a 1/2" fitting takes a 5/8" od pipe.

[Eeyore]

Which is very much what we were used to under the imperial measurement system.

 

[Tracy D'arth]

32 minutes ago, Eeyore said:

There is an interesting note/warning at the top of this page https://keithspecialty.com/plum.Qest fittings.htm   This might suggest that the installation is nominally 3/8"?

It is very thick walled pipe, hence the lack of inserts.

[Tony Brooks]

2 hours ago, Rose Narrowboats said:

It's called Qest and often "mispelt" as Quest.

 

It's still available in the US. I don't know of a UK supplier, but it can be ordered via Amazon. Get a straight coupler (part number QAC43R), take the nut off one end and use the male thread to connect a 15mm fitting to.

 

The threads are 1/2" NPT rather than BSP, but that's never been an issue on Shurflos etc.

 

My thanks also for that gem of information. It would have been gold whilst we still had the boat.

[Eeyore]

Useful table at top of this page.  https://mobilehomedepotmi.com/plumbing/qest.html

[Tracy D'arth]

1 minute ago, Eeyore said:

Useful table at top of this page.  https://mobilehomedepotmi.com/plumbing/qest.html

I found that when looking for Qest, its a bit expensive when you reckon you have to buy the nut sets as well as a fitting. Anyway all that is coming out and Hep2O or maybe Speedfit going in next week. 

[Eeyore]

Is there much to choose between speedfit and hep2o nowdays?

I had an interesting mix of mark1 and mark 2 HEP2O on my first boat, assembly of the various o rings and grab rings was more or less reversed on the later version.

 

[Tracy D'arth]

32 minutes ago, Eeyore said:

Is there much to choose between speedfit and hep2o nowdays?

I had an interesting mix of mark1 and mark 2 HEP2O on my first boat, assembly of the various o rings and grab rings was more or less reversed on the later version.

 

There is the colour for one. Some prefer the all white look.

Most of my experience is with Hepworth, I started when it was the brown Bartol Acorn and used to do trade evenings for them and later for Hepworth when they took over. We did some very large public building installations with Hep2O, including heating systems over 300,000 Btus and have great confidence in the system.