Joining 20mm galvanised conduit

[chainsawuser]

Hi

I want to use some 20mm galvanised conduit as a long run (6m) of curtain rail !

Am not sure that this is strictly the correct place to post this but since conduit is normally used to run wiring I has hoping for a good response here.

I want to install a curtain rail in an old industrial building to screen some machinary behind it from prying eyes. The curtain rail will need to be 6m long and will be a straight run. It will be attached to a solid wall at either end and a beam at the centre point (3m from each wall). The curtain will be light weight (hessian) and will run on metal curtain rings.

I was intending to use a screwed dome cover (http://www.screwfix.com/p/20mm-steel-screwed-dome-cover-pk-2/67630) at either end to attach to the wall and a 'T' (http://www.screwfix.com/p/20mm-galvanised-inspection-tee/87829) to attach to the centre point beam.

I see that I will need a 20mm die set to cut the thread to allow me to use these couplings.

My problem is that the longest length I can fit in my car is about 2m and therefore, I will need to make the 6m run out of 4 sections of pipe. I will need screw connections to the dome covers and to the 'T' piece but also 2 connections just to join a length of pipe to another length of pipe.

How should I make these pipe to pipe joins ? If I use an 'external' coupler (http://www.screwfix.com/p/20mm-galvanised-coupler-pk10/29385) then this will snag the curtain rings as they slide along the pole. Is there some way of joining the pole 'internally' so that the curtain ring won't snag ?

Thanks in advance.

 

[Monkeh]

Tap an internal thread and use a nipple. Or get 3m lengths delivered.

 

[EFLImpudence]

Get 3m lengths delivered.

 

[333rocky333]

slide a hardwood dowel inside

Or use 25mm with 20mm slipped in the joins to brace it

I would have thought 20mm would sag if unsupported as you plan

 

[Scoby_Beasley]

As others have said get 3m lengths delivered, also get a suitable dia. sized length of all thread and tap the conduit where they join.

 

[chainsawuser]

Thanks for all the replies.

I can see that Screwfix do 20mm nipples (http://www.screwfix.com/p/20mm-galvanised-nipples-pk-5/28777)

Where can I get a tap so that I can thread the internal face of the 20mm pipe ? Screwfix only sell a die.

I'm not sure whether it will sag if I only support it at the mid point (3m). If this is the case then I could support it every 2m instead. This would be more work but at least this would fit in with the max length I can get into my car. Will wait and see how I get on.

 

[Scoby_Beasley]

Hmmm, maybe ignore my last post, seems conduit may be made with a lot thinner walls these days! Stuff I used to play with had 1/82 walls.

 

[Lectrician]

Get a wholesaler to deliver the lengths! They are usually 3.5m

At 3m spans, it is going to sag. Using several joints will make it sag further.

Conduit comes with the two ends pre-threaded. You could come up with a different way to support the middle or the ends, and not worry about threading it.

 

[333rocky333]

A 20mm nipple would be too big even if you did thread the conduit internally,
Why not use a catenary wire instead, 6metre run is nothing and there would be no need for centre support

 

[ban-all-sheds]

A wire will still sag.

 

[chainsawuser]

Thanks for all the replies.

I ended up using a 6mm steel cable (bought from ToolSattion) suspended at either end. It does sag very slightly. I could tighten the rope (using a turnbuckle also bought from ToolStation) but the sag is only very small and I don't want to put too much force on my wall fixings.

Really please with the results. The curtains slide really well on the wire rope (used cheap metal curtain rings from Argos).

Good result !