Making IWBs

[light-man]

Hi all,

 

I was wondering if anyone has ever tried making their own IWBs?

 

I've got a load of unused 1.2m aluminium scaff bars which seem quite suitable for hard-power 4-way IWBs, and was wondering about making up my own for LED cans. It'd simply be 16A or 13A input and then 4 13A sockets along the bar, with a final 16A or 13A out for a link at the end. In my head it seems quite simple, but if anyone has any tips or advice, then that'd be much appreciated!

 

I am aware it might end up better to just stick with a black 4-gang tied off to the bar!

 

Cheers,

Si.

[top-cat]

The difficulty you will have is terminating to the plug. If you use a solid plug on a box mounted to the bar, to plug an extension into, that isn't so bad. But if you want to use a trailing lead, there will be no space to link the 4 pieces of cable together properly. If you do use a solid plug on a box, as opposed to a trailing lead, you need to position it close enough to the end of the bar to get your fingers in and poke the 4 cables back through. As a result of all this, personally I would suggest you use 2x 2-gang sockets, rather than 4x single gang. It is less cable to run and push through the plug hole. Obviously the ideal would be to daisy chain the sockets and end up with just a single cable running through, but I'm yet to find a way to pluck the cable out mid-tube!

 

 

You need to cut holes a fair bit bigger than the diameter of the cable, so that you can push it in from an angle so it travels down the tube.

 

You should line the holes with rubber grommets if you can, to prevent abrasion on the cable.

 

You can use 48mm U-Bolts to secure the back boxes to the tube. These are very cheap and perfect for the job.

 

 

[themadhippy]

ou should line the holes with rubber grommets if you can

No if you can about it,some form of grommet is a must

You can use 48mm U-Bolts to secure the back boxes to the tube

and a few weeks down the line the boxes start twisting as the bolts have worked loose,a better option is http://www.robolights.com/products/smart-socket

 

but I'm yet to find a way to pluck the cable out mid-tube!

simples,run a draw wire down the pipe,hooking it out of each hole,attach your cable to the draw wire,pull it to the first hole,then feed it back into the pipe and pull through the second hole,repeat.

[LXbydesign]

What about DMX ?

 

If your going to all the bother of making short IWB bars just for mains- and then end up lobbing on DMX cable everywhere into your nicely rigged, plugged up pars, you may as well forget the IWB bars and just make up some nice custom looms with DMX & mains in / outs.

 

Then regardless what the LEDS are rigged on - you can get mains & DMX to them quickly and easily and neatly! :)

[top-cat]

 

You can use 48mm U-Bolts to secure the back boxes to the tube

and a few weeks down the line the boxes start twisting as the bolts have worked loose,a better option is http://www.robolight...ts/smart-socket

 

 

I have not come across those before but they are very neat, thanks for the link http://www.blue-room.org.uk/public/style_emoticons/default/smile.gif

 

I don't find the U Bolt thing a problem, they tend to come in standard metric sizes so you can use a nylock up to the max and I don't personally have any problems with them shifting around.

 

But yeah if they're reasonably priced those smart sockets seem to be the way forward.

[light-man]

Thanks all for your thoughts on this.

 

personally I would suggest you use 2x 2-gang sockets, rather than 4x single gang.

 

That's just given me an idea! I could perhaps use one of those moulded 1>2 split cables inside the pipe (if I can find ones where the trails are long enough), that way the joint for the cables wouldn't be a concern as this is what was worrying me most when I originally had the thought.

 

ou should line the holes with rubber grommets if you can

No if you can about it,some form of grommet is a must

 

Yeah, I was definitely going to use cable glands on the drilled holes!

 

What about DMX ?

 

I'd thought about that, but I'm not sure if the 3 x 1.5m link leads would look so bad with the mains sorted nice and neat. It's something which I'm still thinking about, though.

 

 

 

[pjb304]

It'd simply be 16A or 13A input and then 4 13A sockets along the bar, with a final 16A or 13A out for a link at the end. In my head it seems quite simple,

 

I'd avoid using 13A sockets if I were you. If using 15A or 16A connectors all the fuses/circuit breakers are at the distribution panels, whereas with 13A there's a fuse at every join. If a fuse in a plug blows it will always be the one which is the biggest pain to get to to replace.

[Stuart91]

My experience is that trying to make prewired bars for LED is a waste of time - several attempts we had (using looms and also a powered bar which we added DMX to) proved impractical in day to day use.

 

Something like this might be easier and cheaper overall if you put any value on your time. You'll probably need a bunch of small jumper leads, but the advantage is that if you get a different design of par that needs slightly longer ones, it's not a problem and you don't need to bin all your looms...

[light-man]

An all-in-one solution was the other option I was looking at, but I'm in two minds as to whether the cost far outweighs the simplicity gain (which is essentially just saving on 4-way 13A power distro). Having said that, one of the of the companies I work for has some all-in-one dimmer bars in that same style and they're quite handy for sending out on dry hire and simple plug-and-play jobs.

 

I'll make sure to avoid 13A inputs and thru-links, but all our cans are on 13A so it'll have to be 13A outputs, and the cans can't be hard wired as they sometimes end up as up-lighters every once in a while. They can always be changed in the future should I decide on 16A for all of them.

 

I think I'll have a go at making one when I have some spare time, and see if it's actually worth it! Thanks for the tips and pointers, everyone.