Cables on a Bar

[Light Console]

After an argument with a friend over where to stick a cable on a bar, I thought I would get the Blue Room to decide the argument!

 

He thinks a cable should go over the bar so that the nut and bolt don't damage it on movement of lantern and Hook Clamp.

I think this makes it harder to remove a Hook Clamp for a fast change/get out. And in the event of Hook Clamp/yoke failure, the cable remains undamaged from safety bond. Under the bar it is much less likely to get damaged surely?

You decide!

Truss is easy, pick a chord out of the way and off you go!

[Guest lightnix]

For me, the secret of great cabling is to make it as invisible as possible, with "on top" being a part of the plan, along with "away from the audience".

 

One other thing I always do, is to make sure all safeties run between the cables and the bar and not over the cables.

[Paul J Need]

On top! Always! How much harder is it to tape under the bar with all the lights in the way ???

 

A nice little "trick" when triping up a bar is to ensure all the hook clamps are facing the same way, then you can rest the cable on the wing nut before taping. And, don't tape too close to the clamp in case you need to replace a unit........

[gareth]

I think this makes it harder to remove a Hook Clamp for a fast change/get out. And in the event of Hook Clamp/yoke failure, the cable remains undamaged from safety bond. Under the bar it is much less likely to get damaged surely?

Two moot points, really. When you rig a bar, you hang the lanterns first (including fitting the safety) before you cable the bar up, so the safety always ends up underneath the cable. And when you're doing a get-out, you'd strip the cable off the bar before taking the lanterns off, so no issue there either.

 

And as Paul says, as long as you don't tape right next to the hook clamps, you can generally manage to get a hook clamp out from underneath the cable. I've done it myself many times!

 

The best situation is to be rigging in a theatre which has ladder-type flying bars. That's a no-brainer - lanterns on the bottom bar, cable on the top one. Luvverly!

[colinmonk]

I agree, Always on top of the Bar, so much easier... and truss is even easier than just picking a cord, jus lay it on top!

[LeeStoddart]

For me the answer is "both"

 

Three of our LX bars are externally pre-wired. There is a permenent tripe with 20 sockets arranged along the bar. This tripe is under the bar. Lanterns hung on the bar don't foul it and the safety goes round the bar and should not damage the cables.

 

If we need an additional bar which is not pre-wired then (as others have said) we hang the lanterns and their safeties, making sure all the hook clamps face the same way. Then run the cables along the bar resting in the wingnuts. When the tripe is taped to the bar it is going to end up above the bar. The same approach is used if there are additional control cables (for scrollers or rotators for example) to be installed on a pre-wired bar

[Guest lightnix]

A couple more tips:-

 

If there are multicore cables running along the bar, I'll tape them in first and then lay the TRS on top, followed by the DMX. This way, the larger cables form a "firm foundation" for the smaller ones and, if the rig is stripped out with a little forethought, it helps prevent the different types of cables from getting all tangled up with each other on The Out.

 

With TRS, I generally (with a couple of exceptions) work "outwards" from the spider and lose the slack on the rig by running it back and forth along the bar/truss (NOT leaving it as ugly coils ). This adds weight to the rig, but is neater and makes it easier to move any lights that need repositioning.

[Modge]

I agree with all the above so I willn't reiterate however I have to point out that it can be a pain in the case that there are already lamps installed (we have a venue where there is a permanent night club install into which we put stage rigs when people can't fill \ afford our better venue). Trying to get get clamps under already tightly taped down cables is no fun and putting them on top is a hanging offence (no pun intended). Also irrating in those circumstances is trying to derig only the cable you put up.

[erroneousblack]

And as Paul says, as long as you don't tape right next to the hook clamps, you can generally manage to get a hook clamp out from underneath the cable. I've done it myself many times!

 

The best situation is to be rigging in a theatre which has ladder-type flying bars. That's a no-brainer - lanterns on the bottom bar, cable on the top one. Luvverly!

<{POST_SNAPBACK}>

 

As to the first point, why do Cambridge students never figure that out!

 

For the second, just like my lovely new flying that gets commisioned today! :P

[DSA]

And as Paul says, as long as you don't tape right next to the hook clamps, you can generally manage to get a hook clamp out from underneath the cable. I've done it myself many times!

Without wanting to state the obvious, I find that this procedure is best achieved by rotating the hook clamp through 90 degress - then it can be just slid out. This procedure can still be achieved even if the cable is quite tight to the clamp.

 

David

[Stu]

Without wanting to state the obvious, I find that this procedure is best achieved by rotating the hook clamp through 90 degress - then it can be just slid out.  This procedure can still be achieved even if the cable is quite tight to the clamp.

I find this can be extremely tricky when you've got an xA LX bar immediately upstage of the LX bar, and a border immediately downstage of these and you squeezed in between the whole contraption up the 'scope!

 

There isn't enough room to swing a cat, let alone rotate a Alto F or 243 90º upwards to slide it out () so I find just having enough slack in the cable in the first place to be able to get it out senisbly the best thing...

 

Just my €0.02.

 

Stu

[DSA]

I find this can be extremely tricky when you've got an xA LX bar immediately upstage of the LX bar, and a border immediately downstage of these and you squeezed in between the whole contraption up the 'scope!

 

There isn't enough room to swing a cat, let alone rotate a Alto F or 243 90º upwards to slide it out (smile.gif) so I find just having enough slack in the cable in the first place to be able to get it out senisbly the best thing...

OK good point, Stu. Luckily I tend to find I do have a bit of space - especially if I am wiring up the bar whilst it is flown in...

 

Anyhow what is an xA LX bar?

 

Thanks,

David

[gareth]

Anyhow what is an xA LX bar?

A prime example might be if you've got a double-stacked no.1 spot bar, or perhaps a cyc flood bar with a bar of howie battens immediately downstage of it to fill in the bottom of a cloth. Taking the first of these two scenarios as an example, you might have a LX1, with another bar immediately upstage of it designated as LX1A. Its simply a device to get more lanterns into a particular location than you can physically fit on one bar, by splitting them across two adjacent bars.

[DSA]

Anyhow what is an xA LX bar?

A prime example might be if you've got a double-stacked no.1 spot bar, or perhaps a cyc flood bar with a bar of howie battens immediately downstage of it to fill in the bottom of a cloth. Taking the first of these two scenarios as an example, you might have a LX1, with another bar immediately upstage of it designated as LX1A. Its simply a device to get more lanterns into a particular location than you can physically fit on one bar, by splitting them across two adjacent bars.

<{POST_SNAPBACK}>

OK thanks, Gareth. I have always called that LX1.5, or whatever is appropriate...

 

David

[SceneMaster]

I have voted top of the bar as this makes the most sense for a whole host of reasons and you will have a lot of cables underside and inside the clamp if you see what I mean if you went the under the bar way, what if you had a lot of multi to cable up you may not be able to fit it under the bar as there would be too much for the clamp to go round…? Also generally you put the lights on the rig first as how are you supposed to run a cable to a light which isn’t there without spending ages working out how long each cable need to be for each light position you want, seems like a lot more work and you can’t rig cables under the bar if there are light there so it would have to be done first which really doesn’t make sense. Also the on top of the bar option keeps the cables as far from the heat as possible although they all should be heat resistant cables anyway but it still makes sense…