Rigging Scaffold Bars To I beams

[Sam Mottram]

Hi

 

I am planning to rig some scaffold bars up at our church to make some bars for lighting but I have a few questions .

• Can we do this ourself or do we need someone who is certified
  
• What clamps should I use ?
  
• How do I drop them about 75cm
  

We have three I beams running down the roof and I want to put up a 24 meter bar and a 12 meter bar.

 

let me know if you can help or if you need more info just ask

 

 

thanks

Sam

[Neil Hampson]

Doughty do a range of girder clamps ranging from single flange rated at 60 KG upto 500KG SWL that span both flanges of the I beam, these are designed to take an M12 bolt, however as you need to drop the bar down, you can use a length of M12 stud bar and the other end have a half coupler to take the barrel. Bear in mind that th longest length of bar that you will be able to get is 6m, so your longest bar will have at least 3 joints (made up from 4, 6m bars. I would probably suggest that these are rigged as 4 separate bars. If you are using Alloy bars I would space the supports no more than a 3-4m span.

 

Rather than give you a list of parts, have a look at the website and use the search function with a keyword of 'girder clamp' this will give you a better idea of how the parts work and which one is better for your application. also look at the half couplers (eg T57000) for attaching the studded bar to the LX bar

Doughty Engineering

[Rob]

You don't necessarily need to be 'certified', but you do need to be deemed 'competent'. I'm guessing from the tone of your post that you haven't done much stuff like this before.

 

Its relatively easy to do and there are various ways of doing it. Neil's method would be ideal for a permanent installation. If you just wanted to hire the gear for a shorter period you might struggle to find anyone hiring the doughty fittings. Gravlok clamps or beam clamps are much more widespread. The gravlok clamp requires a short length of scaff, to which you could then attach a hanging clamp and then a short steel or spanset to give you the 75cm drop. Beam clamps would provide you with an eye to which you could also attach a steel or spanset.

 

Your major issue is that you need to know what the I beams are capable of supporting. Only a qualified structural engineer can tell you this if you don't know already. You also need to look at the weight loading capacities of the scaff bar to see if it will support the amount of equipment you need it to and you need to look at how close and regular the supports holding the scaff up need to be.

[Pete]

We have three I beams running down the roof and I want to put up a 24 meter bar and a 12 meter bar.

 

There's gona be some serious sag in there!

[pete LD]

24 m is a mother of a lx bar for a church!! thats longer than fly bars in large receiving houses that are supported at 6 points and made of gas pipe or ladder beam which don't sag as much. how far apart are the 3 I beams? that will make a big difference to whether its a practical idea or not!

[Neil Hampson]

Due to the length (and the different length), I had asumed that the bars were to run parallel to the I-Beams, but even so it's still one hell of a bar. The bar would need to be fitted up in sections so would it be easier to rig 3 or 4 short bars instead of one huge one?

Please correct me but I would imagine in a church that there would be little scope of changing the Lx design considerably, I would imagine that a few well thought out 4-6m bars would serve as a better investment, the rest of the money can be used on other parts of the infrastucture, cabling, lanterns etc.

[gareth]

Just to chip in my two penn'orth ... for a 24m span on only 3 points, forget scaffold tube. You're looking at truss - what type you use depends on things like the load, how it's distributed, the distance between pick-up points, etc. Consult a competent rigger.

 

If, however, the bar is running parallel to the beams, then you can indeed do it with scaff (as long as the load isn't too great) - but as has been mentioned, the longest piece of scaff tube you'll get is 6.1m so you'll need to do it in sections. Again, when it comes to suspending things above people's heads, consult an experienced rigger or rigging company for professional advice before you start. Don't rely on the advice you get on forums like this one - you have no way of knowing whether that advice is any good.

[paulears]

and to add to Gareths 'chip in' - forget any form of small format 3 or 4 chord truss like the lightweight types - once you join even three or four 2-3m lengths together it will sag noticeably before you even hang anything on it due to play in the joints. Whatever you put up will need real rigging skills. I'm sure that we know suitable firms - if you post a request, we can all pm you with some suitable people who can help.

[SeanT]

Yep, you're well past the realms of scaff or truss, you need to use ladder beams for anything over 24 feet for scaff (no matter metres!!!) and about 12m as paul says for truss.

[Pete]

We need to know more guys. If its a beam 1m beam 1 m beam 22 m then its looking awkward.