Stand mounted truss - Ladder vs Tri

[BradRWills]

Where to start.....

 

So I'm in a band. I have some lights, and I have some truss. I've been using it in a certain way, in good faith, but I can't find any information which confirms that how im doing things is actually correct.

 

SO.......

I have: 2 X Chauvet InnoSpot Duo (2 heads on each - totalling 4)

2 X ADJ dual moving heads

 

I've also got a Global Truss F32 ladder truss, and at the moment they have Global Truss Stand adaptors.

And I have some Power Drive Wind Up stands, which I'm pretty sure could hoist my car, let alone be heavy duty enough to manage the weight of the lights.

I also have rated half clamps on all the lights, and safety cables on all fixtures as you would hope.....

 

I've been using this truss, laid down flat - so as if it was the bottom section of a F33/Tri Truss.

 

Someone mentioned that might not be the best idea I've ever had - but I can't find any details on that.

Is it a problem? Should the truss be used stood up on its side?

Or is it OK laid flat? It's not holding a huge amount of weight - and the most significant weight is not in the middle section (the innospot duos are at opposite ends). I can't see that a Tri does any additional load bracing in my particular application because the top bar is not supported when it's on the stand?

 

If I should be using it 'stood up' does anyone have any idea of the adaptors I need? I saw the Doughty T58701 clamp, which looked interesting, but I feel like theres more chance of half couplers coming loose in that setup?

 

Any assistance from those who know better than me, would be appreciated!

 

Or should I be using a tri- truss? (in which case, I'm going to need to have a re-think as space is a bit limited!)

Edited October 4, 2021 by BradRWills

[alistermorton]

I'm not a rigger, but I'm pretty sure ladder truss should be loaded when it's vertical, not laying flat like a plank.

[IRW]

I'm not a rigger, but I'm pretty sure ladder truss should be loaded when it's vertical, not laying flat like a plank.

 

What Alister said.

If it's such a low load, could you not just use a scaffold bar instead? What is the span between/extension beyond stands?

 

[kerry davies]

To add to what Ian writes, the wall thickness on your ladder tube is 2mm and, laid flat, is not much if any stronger than a single scaff tube. Thick walled ali scaff tube is 5mm thick.

 

Before going into trilite why not hire a length of thick walled ali and compare what you have with that?

Edited October 5, 2021 by kerry davies

[sleah]

Yes it should be used vertically, unless as other state, the load would otherwise be OK on a single scaff bar.

 

Those Doughty clamps are absolutley the right tool for the job of holding truss in the vertical. If there was any doubt or chance that any part of the clamp could come loose, Doughty would not make or sell them. Assuming of course the manufacturers recommendations are followed.....

 

Doughty are one of the manufacturers (like Unicol) you can be certain to do the job properly.

[sunray]

Yes it should be used vertically, unless as other state, the load would otherwise be OK on a single scaff bar.

 

Those Doughty clamps are absolutley the right tool for the job of holding truss in the vertical. If there was any doubt or chance that any part of the clamp could come loose, Doughty would not make or sell them. Assuming of course the manufacturers recommendations are followed.....

 

Doughty are one of the manufacturers (like Unicol) you can be certain to do the job properly.

 

Personally I'd put Doughty above Unicol but that's not to say I've ever had any doubts. Only problems I've ever had with either is incorrect use/not following instructions (like drilling the drop tubes to take a through bolt).

[skinda0]

I had a similar issue selecting an adaptor for truss, I eventually settled on two of these My link in conjunction with my pair of Doughty wind up stands.

I liked the look of these over the Doughty adapters as the centre of mass was kept over the top of the stand rather than off to one side, albeit by 100mm or so.

 

The Doughty stuff is built very well, and as Sleah says, if it wasn't safe they wouldn't sell it!

[BradRWills]

Hey everyone

Thanks so much for your inputs on this. I went with the Douughty Adaptor in the end, as I'm going to offset that 100mm off centre element with a rail to hold a backdrop anyway (which is why I hoped a ladder was OK laid flat - backdrop on the back, lights on the front.....alas...no such luck!)

 

I also had to buy some spigot housings for my stands....turns out the square sections on my stands don't take a standard TV Spigot (of course they don't - that would be WAY too simple).

 

So now, I'm a couple of hundred quid lighter - but less worried about a PLI claim for incorrect use of truss etc!

 

Thanks all for the advice - will post a photo when I've reworked the whole rig, so show you how it all came out!

Brad

 

[BradRWills]

And so this is where we landed (I meant to post this ages ago)

Thanks to everyone who helped - I’m much happier about the rig than I was, and I’m pretty pleased with how tidy its come out! 

[BradRWills]