Imperial Conduit Problem? Imperial Dies?

[GarryJ]

Evening.

I was wondering if anyone knew or has sourced Imperial metal conduit Dies?

I have a job coming up in an old mansion house where there is existing imperial conduit drops down to a consumer unit location above a ceiling which is accessible through a large hatch right at the DB. The customer however wants to raise the ceiling and I am going to need to fit new board etc which is not a problem. However there are 5 existing imperial conduits come down through the ceiling above which I am going to need to very carefully cut them at a higher location and try to run a new thread on them further up where I can bring them into a large galv joint box and get appropriate lockrings etc etc for them to remain a good earthing system with the single core pvc cables within them.
Unfortunately I would have liked to lift the floor above and take the pipes back to the next box and re jig and rewire it all from there but this is not possible due to massive newly tiled floor bathroom above.

I am aware of the imperial to metric adaptors however I need to cut the pipes further up and then re thread. Anyone any other ideas? I could obviously put earth clamps round each of the 5 pipes at a nice clean location but this would look a bit scabby I think

Cheers in advance for any thoughts

 

[westward10]

Still got a set in the garage, only place I can think of is Ebay.

 

[Pete999]

You have 5 metal conduits coming through the ceiling and you want cut them and re thread then in situ, well I wish you all the luck in the world Garry, without a picture it's difficult to advise but personally I think your idea is a non starter. What circuits are in these conduits?

 

[Des 56]

There is a stock and dies set now on ebay of 3/4 and a inch for £25

 

[davesparks]

If they're raising the ceiling then surely you'll have access to the nearest joints from below once the old ceiling is removed?

 

[gaz76]

could you not cut the tube high up as you say, and then put on the imperial to metric adaptors(which hammer on if I remember correctly?) and then just bush into your board?
if it's high up next to the ceiling no-one should see it anyway?
but like has already been said it's going to be tricky cutting the tube, and not sure how you could thread it even if you do get imp dies

 

[davesparks]

I've never seen an adaptor which hammers on, only the threaded type.

you could make up your own adaptors which fit via a set screw if you've got access to a lathe, or else get a local engineering company to make some.

 

[GarryJ]

Ye I know its not an easy one. I will take a photo on my next visit and all will make sense. I had thought of putting a piece of wood in between the wall and the pipes to prize them out a bit to allow me to thread them. I was just thinking of a good decent way to earth the existing pipes which I think is mostly lighting circuits coming down through them. Ideally as said I would like to go back to the nearest box for each pipe and crimp onto cables then rewire down into board but not going to have that privilege.
The hammer on adaptors sound maybe the best option so far. Are they reliable for the cpc though bearing in mind its single core in the pipes? Never used them before I don't think

 

[davesparks]

The force required to cut the thread will almost certainly rip the conduit out of the wall.

 

[gaz76]

have had a quick Google for the knock on adapters and found nothing, am sure I've used them was a while back though..sorry

 

[davesparks]

have had a quick Google for the knock on adapters and found nothing, am sure I've used them was a while back though..sorry

That kind of conduit fitting did exist many many years ago, but they weren't allowed to be used as cpc then.

 

[Dave OCD]

I'd be tempted to save a lot of grief here and just earth the conduits with pipe clamps and cable but done very neatly, or you could link all of the conduits with steel or copper strip clamped around and one earth conductor.

 

[davesparks]

I'd be tempted to save a lot of grief here and just earth the conduits with pipe clamps and cable but done very neatly, or you could link all of the conduits with steel or copper strip clamped around and one earth conductor.

I don't think regular pipe clamps are rated for fault current.
You can get pipe clamps for use in lightning protection systems which presumably are rated for higher currents.

 

[Dave OCD]

That's odd Dave as that's what pipe clamps may have to deal with in unfortunate circumstances ? Then again some nice thick copper strip bolted through between each conduit to create a sort of sandwich would do the trick.

 

[GarryJ]

Thanks for the replies guys. Its a difficult one. Will take a photo and upload it to show the problem better.
The bathroom above the location looks to be around £400 per floor tile and about the size of my full house

 

[davesparks]

That's odd Dave as that's what pipe clamps may have to deal with in unfortunate circumstances ? Then again some nice thick copper strip bolted through between each conduit to create a sort of sandwich would do the trick.

Bizarrely I did have a copy of the actual spec for a bs951 clamp somewhere, I'll see if I can find it.
Just looking at them I wouldn't trust them as part of a cpc, but maybe that's just me.

 

[Dave OCD]

Thanks for the replies guys. Its a difficult one. Will take a photo and upload it to show the problem better.
The bathroom above the location looks to be around £400 per floor tile and about the size of my full house

You may have to forget your usual rates here and price to reflect the nature of the job, sounds like they can afford it.

 

[7029 dave]

could you not cut the tube high up as you say, and then put on the imperial to metric adaptors(which hammer on if I remember correctly?) and then just bush into your board?
if it's high up next to the ceiling no-one should see it anyway?
but like has already been said it's going to be tricky cutting the tube, and not sure how you could thread it even if you do get imp dies

I have heard of this type of adaptor, but never seen one.

 

[Dave OCD]

Bizarrely I did have a copy of the actual spec for a bs951 clamp somewhere, I'll see if I can find it.
Just looking at them I wouldn't trust them as part of a cpc, but maybe that's just me.

Some brands are definitely better made than others that's for sure.

 

[GarryJ]

They definitely can Dave cost is no problem here however shortening these pipes and trying to maintain a good CPC using the pipes is haha

 

[Dave OCD]

Just cut them as neatly as you can and 'bond' them Garry.

 

[davesparks]

How are you going to get the cables out of the pipe to cut the pipe?

 

[Dave OCD]

That's a good question too.

 

[Toneyz]

There is a manufacturer of conduit that I think does up by Alan key it apparently has full B.S approval just a thought

 

[westward10]

There is a manufacturer of conduit that I think does up by Alan key it apparently has full B.S approval just a thought

Electric Centre had this in their catalogue at one time but now it has disappeared maybe it didn't catch on.

 

[Toneyz]

Conlok conduit systems that's the name google it. Used them knock on conduit adaptors as posted above IMO I would not rely on it for earth continuity. Although conduit has to be electrically sound is it being used as the C.P.C.

 

[westward10]

I have tried threading in situ conduit without success. The force needed to thread it can shear off the upper termination and even trying to hold it with pipe grips just spins it.

 

[LankyWill]

Please video yourself attempting to thread and cut the conduit in situ, if you can manage it you will become a legend throughout history.

 

[davesparks]

There is a manufacturer of conduit that I think does up by Alan key it apparently has full B.S approval just a thought

They don't manufacture it in imperial sizes though. And it's utter rubbish, it was used locally in a new entertainment venue. We did the first show in the venue and those conlok fittings were already failing in places where they'd had a little tap.

 

[Wilko]

You have 5 metal conduits coming through the ceiling and you want cut them and re thread then in situ, well I wish you all the luck in the world Garry, without a picture it's difficult to advise but personally I think your idea is a non starter. What circuits are in these conduits?

Also my thought, I'm imagining all kinds of collateral damage cutting, removing, threading and installing while working up a ladder 4m ... hopefully I just need my happy pills.
Maybe leave in situ and adapt at the CU? Then you can adapt/bond/clamp or whatever in the privacy of your own home.

 

[KennyKen]

The only time I've threaded conduit in situe was with an small arm electric threader and a full tub of lanolin. Make sure the cuts straight. Was a pain the the --- when the cuts slightly off.

 

[Allan Hogg]

Hi, I see the conduits are in an old mansion. In this case the conduits could be gas threaded and strangely enough 3/8 gas threaded conduit is the same size as 16mm so your metric dies may do the job. I did have sets of gas dies and imperial dies when I was an apprentice in the 50s. to connect to old conduits.

 

[Pete999]

How are you going to get the cables out of the pipe to cut the pipe?

The OP I believe did say when asked if he could pull the wires back, he mentioned that the floor above was tiled, so pulling the cables back is a no no, this leads me to what davesparks has asked. someone else asked if the OP would film his attempts to do what he has suggested, hope it's posted on the forum.