ProSoundWeb Community

Please login or register.

Login with username, password and session length
Advanced search  
Pages: [1] 2  All   Go Down

Author Topic: Using electric winch to fly lightweight truss... and liability  (Read 11776 times)

Adam Ellsworth

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 63

Hello,

Life in the gig world has just been really good the past year or so, I need to be brought back down a peg:

I've thought on and off for a year about getting two reasonably-priced electric winches and attaching them to a truss for flying. I do a few venues regularly and to get the front truss up I've been using two Applied lifts temporarily and then dead-hanging the truss. It works, but really slows down the process because we have to set the lifts, build the front truss, hang it, and break the lifts back down before we can build the back truss. Likewise at the end of the show the front truss can't get to work until the entire stage is pretty much out.

I'm thinking a pair of $100 to $150 electric winches like these:
http://cgi.ebay.com/Electric-Hoist-880-lb-New-w-Warranty_W0Q QitemZ200085925210QQihZ010QQcategoryZ61574QQrdZ1QQcmdZViewIt em

I would estimate total weight of the truss around 150lbs. So even at 440lbs capacity it's rated at 4 times the load. And they're 1200 watts at 120v, so it'd be easy to build a pickle-extender and run them from the ground. But I'd imagine these are stamped "not for overhead lifting" and language like that... at least they're UL listed, if in fact that's worth anything in this case. (They won't start on fire at least?)

So my question really is less about logistics and more about "is this just a really bad idea?" I always use two safeties (redundant hanging methods) and still get nervous flying anything, which is partly why I haven't already tried this. I could (and probably would) still dead-hang these once in the "up" position and take the weight off the winches. But how does flying things above crowds affect liability insurance... is that something I need to have actually noted? Or will they refuse to cover it? And is this the kind of thing where insurance won't cover anything without a licensed rigger? Maybe that's what this thread should have been about anyway... general questions for the future, at least I'm not doing this yet.

... and is there a good agent for gig liability insurance? My current agent is clueless and I think I'm not well protected.
Logged

Phil LaDue

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 4039
Re: Using electric winch to fly lightweight truss... and liability
« Reply #1 on: March 06, 2007, 06:08:15 PM »

Math wise they look ok, but no insurance adjuster or inspector would be enthused seeing engine hoists used to rig truss!

Phil LaDue

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 4039
Re: Using electric winch to fly lightweight truss... and liability
« Reply #2 on: March 06, 2007, 06:09:46 PM »

Adam Ellsworth wrote on Tue, 06 March 2007 17:26

I've thought on and off for a year about getting two reasonably-priced electric winches and attaching them to a truss for flying. I do a few venues regularly and to get the front truss up I've been using two Applied lifts temporarily and then dead-hanging the truss. It works, but really slows down the process because we have to set the lifts, build the front truss, hang it, and break the lifts back down before we can build the back truss.


Why not just get two more lifts?

Adam Ellsworth

  • Jr. Member
  • **
  • Offline Offline
  • Posts: 63
Re: Using electric winch to fly lightweight truss... and liability
« Reply #3 on: March 06, 2007, 07:03:45 PM »

Phil LaDue wrote on Tue, 06 March 2007 23:09


Why not just get two more lifts?


Winches is cheap, and awesome. I really like pushing a button and having things move. Also, I just don't have it in the budget for another set of good lifts. I really need to sit down and prioritize the next year or so of purchases and I'm avoiding that. While I'd like to spend money on things to make setup more efficient, there's a point it's not good business for the volume I'm doing. I need a new distro more than I need lifts.

It's just a dream, really. But I do need to figure out liability insurance, been getting by without for too long and my summer's looking fairly busy. I'm sure that's been covered in a few threads.

Thanks!
Logged

Mike Slay

  • Full Member
  • ***
  • Offline Offline
  • Posts: 233
Re: Using electric winch to fly lightweight truss... and liability
« Reply #4 on: March 07, 2007, 07:01:46 AM »

Here are some considerations.  Your typical CM chain hoist has a couple of important safety features.  It has a brake that engages when it loses power.    Also a Chain hoist has a limit switches.  Does your winch duplicate these safety features?  

Also can someone certify your winch for overhead lifting on an annual basis?   This documentation is crucial from a liability stand point.

Also I assume you still intending to dead hang.  You're just using the winch to lift.
Logged
What's the difference between a Monitor engineer and FOH engineer?  Monitor engineers can do both.

len woelfel

  • Hero Member
  • *****
  • Offline Offline
  • Posts: 582
    • http://www.party-chicago.com/rentals/rentals.html
Re: Using electric winch to fly lightweight truss... and liability
« Reply #5 on: March 07, 2007, 07:47:28 AM »

Mike Slay wrote on Wed, 07 March 2007 06:01

Here are some considerations.  Your typical CM chain hoist has a couple of important safety features.  It has a brake that engages when it loses power.    Also a Chain hoist has a limit switches.  Does your winch duplicate these safety features?  

Also can someone certify your winch for overhead lifting on an annual basis?   This documentation is crucial from a liability stand point.

Also I assume you still intending to dead hang.  You're just using the winch to lift.



Ditto.  

What about renting?

Mac Kerr

  • SR Forums
  • Hero Member
  • *
  • Offline Offline
  • Posts: 10223
Re: Using electric winch to fly lightweight truss... and liability
« Reply #6 on: March 07, 2007, 12:43:51 PM »

You can't have much on that truss if the weight including cable is only 150lbs. If you can't afford a couple of 1/4 ton chain motors, get a couple of manual chain hoists. These are available in versions intended for entertainment use. With enough lifting capacity you can load your truss and cable it while it is 4' off the ground, and lift it to trim ready to focus. If your truss really is that light, you could use a couple of rope block and falls to lift it, and then dead hang it.

Mac
Logged

Jordan P.C. O'Neil

  • Full Member
  • ***
  • Offline Offline
  • Posts: 128
Re: Using electric winch to fly lightweight truss... and liability
« Reply #7 on: March 07, 2007, 05:27:13 PM »

Mac Kerr wrote on Thu, 08 March 2007 06:43

 If you can't afford a couple of 1/4 ton chain motors, get a couple of manual chain hoists. These are available in versions intended for entertainment use. With enough lifting capacity you can load your truss and cable it while it is 4' off the ground, and lift it to trim ready to focus
Mac


Dang! beat me to it!
I'm a big fan of using (appropriate) manual chain blocks for lifting truss, PA etc. to a dead-hang. Usually they will take less time to set up as they are much lighter than motors, and there is no power/control cabling to be done.
I'd say the threshold for efficiency is over 7m, or more than 3 points on one lift, beyond that manual hoisting becomes tiresome or difficult.
Always consult your rigger when it comes to purchasing something like this, and the necessary hardware to go with it.
Logged

Michael King

  • Full Member
  • ***
  • Offline Offline
  • Posts: 119
Re: Using electric winch to fly lightweight truss... and liability
« Reply #8 on: March 08, 2007, 01:50:41 AM »

how do you plan on getting these saftley attached and able to pull the trussing up? they look like they have to be mounted to something almost permantly. i dont know the room you plan on doing this in but it has to have hanging points that can support the weight. i would look at the manual hoist, and check with the venue first make sure its ok.
Logged

Brad Trower

  • Newbie
  • *
  • Offline Offline
  • Posts: 18
Re: Using electric winch to fly lightweight truss... and liability
« Reply #9 on: March 17, 2007, 11:01:36 PM »

I've used those same hoist that you are talking about and we even have one at the motorcycle shop i work at and use it to lift jet skis up to put them on the trailers. they hold fine no slipping or anything. but when i use them the lift truss or pipe i always take a chain and once its in position chain it up so there is no possibility of the rig coming down. I am always worried of the worst happening so thats why i use the chain once its up there, but thats just me. hope this helps
Brad
Logged
Pages: [1] 2  All   Go Up
 

Site Hosted By Ashdown Technologies, Inc.

Page created in 0.029 seconds with 20 queries.