Rigging Thomas PRT To Genies?

[to5002002]

Anybody have any pointers on how to rig Thomas 30" x26" PRT truss to Genie ST25 Lifts. Is any type of adapter plates on the market for this, or would I have to get them custom fabricated? I havn't been able to find a very convenient way to rig the truss to the forks especially with those angled bolt plates at the end of the truss.

[Tomo]

I'm not a rigger, but I'm fairly sure that Genie SuperTowers are not intended to be used as rigging points, and the user manual for SuperTower II seems to support that notion. (Direct link to PDF)

 

Page 3 says:

Do not stand under or allow personnel under the machine when the load is raised.

Do not stand under the load. The safety brake system will allow the load to drop 1 to 3 feet before locking the columns

 

That really doesn't sound suitable to me.

I've only seen these used to raise and lower a truss (often with fixtures pre-rigged) onto/off pre-built ground support trussing to minimise work-at-height.

 

I think the truss was usually load-strapped onto the forks during the lifting/lowering operation, with the lifts taken away after placing the beam onto the ground support.

[ianl]

I believe that whilst they were not origonally designed for truss lifting, (they were designed more for air con ducting lifting) the later models were more suitable, cant remember which was which, supertower or superlift (I called them all superlifts) 15 years ago it was common practice to stick 40ft of truss on a pair, in fact in the civic hall size venues it was more likely to see superlifts than motors

 

that said I'm quite glad they are used less now (although I do see them ocasionally) I was never convinced about them, how well serviced they were, the fact that the loading on a pair was not much more than a 40 ft truss, climbing the genie to get on to the truss scared the sh1t out of me, and when they broke they broke fully extended (repacking the just loaded artic to fit a 30ft long mast that weighs a few hundred killos is one of my least favorite sports, just below getting a 40ft fully loaded truss off a stuck up superlift) also when tipping the artic a bar of 6 flightcase and a superlift flightcase look very similar until you get to the centre of gravity shift

 

anyway back to the op question, I dont recall ever seeing prerig on superlifts, it was generally 12"x12" or more likely A type. either the forks had scaf clamps welded onto them or we just used ratchet straps, sometimes a scaff bar across the forks and then the truss sat on that

[jonathanhill]

Anybody have any pointers on how to rig Thomas 30" x26" PRT truss to Genie ST25 Lifts. Is any type of adapter plates on the market for this, or would I have to get them custom fabricated? I havn't been able to find a very convenient way to rig the truss to the forks especially with those angled bolt plates at the end of the truss.

 

Really wouldnt recommend using Superlifts in this way. I have only ever seen them used to lift a truss into position, usually as part of a ground support system. In my view they are horrible, fragile and unstable lumps. As for climbing them - s*d that!!

[boac]

The Genie Super Tower ST25 is indeed suitable for supporting truss during the gig, and I for one still use them regularly to do so, especially at festivals on stages that are in tents and therefore have nowhere to hang motors. Not a massive fan, I must admit, but they do get the job done. I've not used them with pre-rig but the photo on Genie's website shows one lifting what looks like pre-rig. Not the best photo so don't know if it's any help to you. Looks to me like they've got the forks stuck in the end of the truss, rather than under the bottom chord.

 

As for maintenance and breaking... Once turned up one morning and noticed that the front truss seemed a bit on the wonk. Closer inspection revealed a loose cable on one of the Genies. The forks had dropped a few inches onto the brake. Several phonecalls to Genie later and the answer was that it was safe to leave it in place. We got another one in for the load out to take the weight of the truss, tipped the broken one over still extended but were fortunate enough to avoid re loading the artic as we had instructions from Genie on how to release the break and a special tool to do it with. The cable had not snapped anywhere along its length, it was the point where it was anchored onto the structure that failed. The lift in question had only just been professionally serviced. Fun and games!

 

 

 

I'd never climb up one though!