Cantenary wire for an exhibition stand

[Stuart91]

In a couple of months time I'm putting up an exhibition stand for a customer, with the typical truss box going around.

 

The client wants to extend a couple of wires across the stand, and hang a couple of lightweight banners from them. It's essentially a cantenary style wire, and needs to be under enough tension that it doesn't sag with maybe a couple of kilos of banners hanging from it.

 

I'm planning on using half-coupler style clamps with eyelets, and attaching the wire via shackles, with maybe a turnbuckle to tension it. I can easily get this made up for me, since I know the dimensions of the truss, but I'm wondering if, rather than having a rigging house crimp up some cable for me, there is an off-the-shelf solution that would be effective?

[Simon Lewis]

Would one of the Reutlinger type accessories make the job simpler? The catenary wire goes through the centre and the collet knob locks it off. It's possible that a turnbuckle might be needed at one ends, but it's a fairly quick and easy solution that doesn't require the steel wire rpoe to be fuly terminated? Here's one of their devices with a half coupler......

[alistermorton]

Could you do anything with gripples to avoid having to crimp stuff to the cable?

[Stuart91]

Thanks, the Reutlinger stuff looks interesting. Gripple may well be an option. I'd be keen to be able to deal with cabling on site, rather than rely on bringing perfect pre-made lengths. I suspect they may have a few extra ideas so being able to come up with bespoke lengths on site would be handy.

[peza2010]

That sounds like a hell of a lot of faff to have it premade before hand.

 

 

For a couple of hundred quid at most you could set you up with a crimp kit, tool and a reel of catenary wire etc. Then just treat the wire as a consumbable.

[J Pearce]

Depending on the span and finished aesthetics a bit of 6mm sash and a good knot at either end (maybe a hitch with some loops to give mechanical advantage on pulling tension) could do fine.

[ontoprigger]

Wedge sockets are a much more cost effective alternative.

 

https://shop.flints.co.uk/Products/pg_WedgeSockets?catdesc=Wedge-Sockets

 

You will need to watch how tight you make the wire, a 2.5 kg load in the middle of a 6m span on a wire that is tight enough to look level can excerpt a load of over 400 kg's on the truss and a 5 Kg load on the same wire is going to get up to 700 Kg's +. Side load is not going to be in any span tables you can get and most truss manufacturers don't rate the truss for side load, especially to that degree.

 

Could you do anything with gripples to avoid having to crimp stuff to the cable?

 

 

 

gripples are not suitable for suspending loads.

[empyfree]

 

Could you do anything with gripples to avoid having to crimp stuff to the cable?

 

 

 

gripples are not suitable for suspending loads.

 

That's a bit of a sweeping statement surely?

http://www.gripple.co.uk/us/us/a101/t2

[ontoprigger]

Could you do anything with gripples to avoid having to crimp stuff to the cable?

 

 

 

gripples are not suitable for suspending loads.

 

That's a bit of a sweeping statement surely?

http://www.gripple.co.uk/us/us/a101/t2

 

 

 

Sorry it was not supposed to be, but they were not rated for and marked for suspending loads and therefore in Europe should not be used to suspend loads, Gripple always used sell these as tension, repair devices for fencing and they always used to say not suitable for lifting on the packet, I haven't used them in years so maybe they have changed the wording.

 

We tested them and found that they would hold 400-500 Kg's before they stripped the teeth.

 

Having said all that and gone away and done some reading they are now rated so could be used for suspending loads, thanks for picking me up on that, although I would still prefer one of the alternatives, as they are a one use device and I believe still don't meet the requirements as lifting equipment as the testing was done as part of HVAC systems.

 

http://www.gripple.c...ds/TUV-CERT.pdf

[Seano]

Thanks, the Reutlinger stuff looks interesting.

 

If you want to keep a stock of adjustable drifts, there's a lot to be said for a crimped eye at one end and a Reutlinger at the other. (None of the wacky variations, a simple eye is much more versatile.) And if you're keeping it, rather than treating the wire as a consumable, it's also available in black.

 

a bit of 6mm sash and a good knot at either end

 

There certainly are times that a bit of string is a marvellous thing.

I don't think I'd really want to hang the banners on sash in this case (the way I'm picturing the OP's scenario anyway), but you're not properly equipped for any job involving banners and graphics if you don't have a decent supply of string imo. (4mm cord for me, as a get-out-of-jail-free card. And a bag of hold-ons if there's drape involved.)

 

Wedge sockets are a much more cost effective alternative.

 

As a budget alternative to a Reutlinger with similar (but more fiddly) functionality, a bullet (Strandvise) is more likely the way to go.

 

Valid points regarding sag - zero sag is not an option on any catenary. (Because zero sag implies infinite tension.)

 

If hanging rigid branding (correx signage and the like) from a catenary, and it absolutely must be level, the way to go is to drop it from the wire on strings that can be adjusted afterwards to get the sign perfectly level if (when) the catenary is not.

 

For a flexible banner, printed vinyl and the like, you can usually get away with a wee bit of sag. But if you have the time and the need for a great deal of fannying about to eliminate it, hang the banner on a catenary between the bottom chords of the truss. Put in a second one between the top chords and pick up the lower one here and there with a string. The top wire sags, and the strings pick up the bottom wire at intervals so that one doesn't, exactly like a suspension bridge. Takes absolutely ages the first time, gets quicker with practice. Do it at floor level if you possibly can, before the truss goes up.

[Stuart91]

Thanks, everyone. There's a lot of helpful stuff here.

 

The stuff that is being hung is actually samples of fabric so might be lighter than PVC banners. My 2kg estimate was perhaps a bit over-generous.

 

We are going to be loading lighting etc. at floor level so should have time to fit the cantenaries before the truss is lifted.

 

Good point from Seano about "zero sag". I guess what I'm looking for is "sag that is imperceptible from floor level" or more accurately "sag that the customer won't complain about"...