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Sound Reinforcement - Forums for Live Sound Professionals - Your Displayed Name Must Be Your Real Full Name To Post In The Live Sound Forums => SR Forum Archives => Lighting FUD Forum Archive => Topic started by: Tony "T" Tissot on June 22, 2007, 05:10:28 PM

Title: "Semi-permanent" hoist - light duty - suggestions?
Post by: Tony "T" Tissot on June 22, 2007, 05:10:28 PM

Any suggestions for a lighter duty, semipermanent set of hoists for a load of no more than 300 lbs (I'll probably spec 1/2 ton).?

I am well familiar with the "real stuff" (CM lodestars) - and counterweight fly systems.

Wonder if there are any other budget strategies for a 2-point load, 20 feet (cheap tri truss - or batten) that does not cost so much, or require installation of a real line set.

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Ron Hebbard on June 22, 2007, 11:57:35 PM

Tony Tissot wrote on Fri, 22 June 2007 22:10

Hi Tony;

Without a clear idea of what you're up to, possibly two lengths of aircraft cable, over two (or three) pulleys and terminating in a common clew.
When it's out the common clew could be hooked to a point at head height.
One of the tiny CM's could be used to muscle the common clew off it's point and lower the load in.
Leave it on the hoist when in and take the hoist away when out.

Just a thought.
Of course you could do the same thing with one set of chain falls for even less money.

Possibly with a little more info, and a better understanding, more people would reply.

Toodleoo!
Ron Hebbard

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Tony "T" Tissot on June 23, 2007, 03:45:21 AM

Thanks Ron -

The chain falls might work. But what do I do with the chain? I can't leave it hanging. I am used to electric hoists with chain bags and remote control - with the remote wires running along the electric feed.

Do I have to climb a ladder to hide the chain in normal canvas chain baskets? I assume I don't want the hoists with the locking handle at the attachment point?

It's really for saving me time:

Simple rig at a place I do 24 shows a year at. I currently load in 18 foot towers and 26 feet of truss. I have to clear floor space after the shows. I would like to leave a lot of the rig up. Needs to go up and down - as I put 16 to 32 pars + movers + dimmer packs on it. And I have to get the lights out for occasional light rental gigs. I can leave the stuff much of the time.

I checked into "real" line sets (4 point, with counterweights), and some used electric hoists - that starts at about $2K US used. $4K for a "real" installation!

There are 4 steel mini I-beam roof truss, perpendicular to the stage. I would like to rig something to that. The hang would either be spare 1" X 12" triangle truss or 1.5 inch pipe that I could leave in place.

And I am afraid to do line sets without counterweights. That's why hoists seem (correct me - please!) more appropriate.

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Dan Glass on June 23, 2007, 06:34:46 AM

The easiest solution for me would a couple of single phase 1/4 ton CM motors. They are lightweight and easy to move around but will carry the load you are looking to hang. Then when you are done you could leave the motors and just remove the power and control for safety. Hang them using steel flex and you shouldn't have any worries when you leave them behind. Other than motors then I guess a chain fall would be next because it doesn't need power but then you will need to get up on a ladder and hide/secure the chain. Hope that helped.

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Ron Hebbard on June 23, 2007, 05:29:53 PM

Tony Tissot wrote on Fri, 22 June 2007 22:10

Hi Tony;

Let's try this again.

You began by speaking of two points.

I was envisioning two sheaves, one at the top of each pick point.
Possibly these would be suspended from welded link chain, or aircraft cable, wrapped over your overhead beams.

You could run aircraft cable from an attachment point on your truss or pipe, up, through one of your overhead sheaves, across to a sidewall, through another sheave serving as a head block, turn 180 degrees with a thimble and Crosby, back up through a second headblock sheave, across to your second overhead sheave and back down to an attachment point on your truss or pipe.

One piece of aircraft cable with both ends terminating at your truss or pipe and a 180 degree turnaround near it's mid point.

When the truss is in, the 180 degree turnaround is just below your headblock.
When the truss is out, the 180 degree turnaround is approximately head height and secured to a point on the wall.
A padlock could be added to keep helpful fingers from grunting the turnaround off of it's point.

When you arrive, you could use either a small CM Lodestar, or a set of chain falls anchored to a lower point to pull the 180 degree point down off it's head height tie-off point and then to raise the point and lower your truss.
The CM or chain falls would remain near floor level paying out chain upwards as your truss comes in.
When your truss is back up to trim, you'd secure the 180 degree point back to the wall and take your CM / chain falls away with you.
This would mean working with your truss at the same high trim all the time and having two points on a wall; one to secure your truss when out and a second, lower, to anchor your CM / chainfalls. On the wall, you could add a safety from your upper load bearing point to your lower rigging point as additional security when you're not on site.

Just an economical thought bearing in mind that I can't see your space from here and have no idea if you have a suitable wall, or vertical steel column, anywhere near convenient.

Toodleoo!
Ron Hebbard

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Tony "T" Tissot on June 23, 2007, 10:49:34 PM

Ron -

Now I see it clearly! Problem solved - Thanks. I might use a chain hoist (with the bottom fixed) right against the wall - I can do this inexpensively - yet safely.

I'll CAD this out. I do have a wall - unfortunately it's aluminum studs, but I can spread the load and reinforce.

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Ron Hebbard on June 24, 2007, 12:02:26 AM

Tony Tissot wrote on Sun, 24 June 2007 03:49

Hi again Tony;

A couple of bonus thoughts;

Two small weights, one on the end of each pick, would let you take your truss / pipe away if necessary.
A small clew plate would let you turn your 2 line set into a 3 or 4 line set if needed.

Toodleoo!
Ron Hebbard

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Kit Hannah on July 01, 2007, 10:43:45 PM

Why not just do some manual chain hoists? Most any rigging shop can order you manual 1/2 or 1 ton hoists with custom lengths of chain (we used to use 30 footers). Those can be had for less than $200 each and you're not having to monkey something up.

Just my 2 cents...

Kit

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Ron Hebbard on July 02, 2007, 01:14:55 AM

Kit Hannah wrote on Mon, 02 July 2007 03:43

Hi Kit;

Tony spoke against chain falls thusly in post number 221929 on Saturday June 23rd/07:

"The chain falls might work. But what do I do with the chain? I can't leave it hanging. I am used to electric hoists with chain bags and remote control - with the remote wires running along the electric feed.

Do I have to climb a ladder to hide the chain in normal canvas chain baskets? I assume I don't want the hoists with the locking handle at the attachment point?"

Toodleoo!
Ron Hebbard

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: E. Lee Dickinson on July 04, 2007, 09:30:52 AM

Some good advice in here, some bad. First, wrapping a beam with chain: Not a good idea. Chain, even welded proof coil chain, is not designed to be side loaded. A chain link resting against the edge of the beam is a weakened chain link, and would not pass the scrutiny of an inspector who knew what he was looking at.

Second, using motors for any kind of permanent install: We ALL do it. We have all been to clubs that do it. This is standard accepted practice in our clubs and in our touring industry.

Unfortunately, the first page of CM Lodestar manuals say to use the hoist for lifting, then secure the load. Do not use while anyone is under it, etc. So again, knowledgeable inspectors will fail a load hung solely from a motor lift not specifically designed for such.

I have been failed for the first item (chain around a beam), but luckily never for the second item. I secure the load to the ceiling on about 60% of jobs.

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Kit Hannah on July 04, 2007, 09:06:17 PM

Yes, thanks Ron, I did see that, but monkey-assing a chain to hold everything up is going to leave 2 options...1, you'll still have chain cming down somewhere, or 2, you'll have to use a ladder.

If you wan to get really trick, you can go with this system they have in the National Guard base here - they have 10 ton moving winches along I beams that are controlled with a wireless remote. They use them to pick up their hellicopters. Very cool stuff, but probably just a couple of dollars out of your budget...

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Ron Hebbard on July 04, 2007, 11:00:53 PM

Kit Hannah wrote on Thu, 05 July 2007 02:06

Hi Kit;

I don't think you're understanding what I meant, it took two passes for Tony to catch on.
I'm suggesting one small chain motor or chain fall is brought on site and used to lower his truss, or pipe, in to working height and then to fly it back out to trim whereupon the chain motor or chain fall is removed and taken off site.
The load is supported by the motor or falls when in and deaded off to an adjacent wall or column when at working height.
The motor or falls stay at floor level and pay out upwards to lower the load.

Back to your #'s 1 and 2;
- 1; No, no chain coming down only chain going up and only while the load is in and not when the load is out to working height.
- 2; A ladder, or such, would only be required for the initial rigging but not after the installation.

Possibly Tony can explain me better than I can, one can hope.
Maybe Tony will let us know how he makes out.

Toodleoo!
Ron Hebbard

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Tony "T" Tissot on July 04, 2007, 11:30:48 PM

Ron -

You have that correct. And thanks for the direction BTW. At no time (save for raising and lowering) will a hoist be in the equation. When flown, the load will be tied off and bolted (upper chain link through thimble of the fly lines, bottom chain link through steel rail.)

I have run into a bit of a snag, however.

I had access to two stage side walls.

- SR I deem insufficient to hold the load, even though it is "always" going to be less than a quarter-ton load. Drywall with aluminum studs. No access to the slab below it. I am not worried about me - but someone inevitably follows that will want to hang the house from "Sunset Boulevard"

- The second (SL) wall has to be torn down and rebuilt due to a very interesting interpretation of the purpose of the wall and it's fire rating by our local (and now out-of-a-job) fire Marshall.

I may have to route the lift blocks straight back to the rear wall to the head block. The rear wall is pre-stressed concrete and will accept epoxied bolts to hold a rail.

I dislike this approach because it adds another set of blocks to get to a single thimble, but it is probably safest. And of course additional line sets would be limited to only one more.

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Ron Hebbard on July 05, 2007, 12:22:02 AM

Tony "T" Tissot wrote on Thu, 05 July 2007 04:30

Hi Tony!

So you've met the house from 'Sunset' have you?
20,000 pounds of 'house' and 20,000 pounds of counter-weight, 20 tons of live load.
Also interesting your mention of tieing back to the upstage wall as this was where the house's counter-weights were located in New York, Toronto and Vancouver. I suspect this was also the case in the L.A. production but I had no involvement with that one.

The shop I was with at the time built the 'On The Road' fly-pieces for Broadway, Toronto and Vancouver but had no involvement whatsoever with the L.A. piece.

Normally when you arrive to deliver an 11,000 pound fly-piece, you're installing the heaviest flown piece in the show but not with 'Sunset'. At 11,000 pounds, our piece was number three with the 14,000 pound pool surround and the mansion outweighing us.

If you saw the mansion, did you see the grid and the mods made to support all of this extra weight?
A nice piece of work, a very nice piece of work.

Based upon our work with 'Sunset', our shop was selected to build the two touring decks and the mansion for the U.S. National tour.

You've taken me back eleven years and thanks for the memories.

Toodleoo!
Ron Hebbard

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Tony "T" Tissot on July 05, 2007, 01:11:08 AM

Ron Hebbard wrote on Wed, 04 July 2007 21:22

So you've met the house from 'Sunset' have you?
20,000 pounds of 'house' and 20,000 pounds of counter-weight, 20 tons of live load.

Yes - but as a 1 time west end, nine-time NY audience member (Lupone in London, Close and Buckley in NY). All the while as a California resident. Backstage time courtesy Broadway Cares, and a personal bribe to the stage manager (his Charity BTW) who remembered me from previous tours.

For some reason then - and still to this day - I count SB as the show that really remade musical theater. Spectacular set, superb music and a story. Too bad it never made a dime! I have never been a fan of the Les Mis/Evita/Lion King/Phantom school of nonsense musicals. I thought, I still think, SB was markedly different.

This is the show that drove me back to doing "semi-pro" equity regional design gigs.

I remembered the 10 Tons for the house - but not the 5 1/2 for the car sequence. I did look at the grid (could not see much and did not get to climb it) and the backstage wall.

I had never imagined counter weights that were expressed in Tons before.

Title: Re: "Semi-permanent" hoist - light duty - suggestions?
Post by: Ron Hebbard on July 05, 2007, 04:03:49 AM

Hi Tony;

Just a few 'Sunset'-isms from memory.

In an oversimplification, the flying of the mansion was akin to the world's largest flying drawer slides with the mansion itself forming the drawer.

There were something like 5 or 6 pairs of hard legs.
Three of the legs on each side, all of the odd or even numbers, I can't recall which, had full height 'I' beams on their on-stage edges.
These 6 vertical 'I' beams began in the basement, ran up through the stage, through the touring deck, through the theatre's own grid and on upwards to create two additional custom grids above the original grid.
The tops of the 6 'I' beams were tied side to side and U/S - D/S between each other and on out to the side and U/S and D/S walls for horizontal stability.

Standard flown items were on the original grid.
Heavier pieces, like the pool surround and our 'On The Road' piece were one level above the normal grid.
The mansion was supported from the top-most level, I suppose primarily to provide clearance for the rigging and the diagonally routed support cables.

On top of each of the six vertical columns was a massive sheave on the order of 24" to 30" in diameter and grooved for a single 1.125" cable. Could've been a 1.25" cable, don't whip me, it was a while back.

Across the centre of the U/S wall were two massive beams supporting six more sheaves serving as headblocks for the counter-weights.
In plan view, these six sheaves were angled towards their respective column sheaves which were, of course, angled towards their headblocks.
This meant that the six supporting cables ran diagonally across above the uppermost grid from the columns to the headblocks.

On either side of the stage, supported by 3 cables each and captured to the vertical columns by a myriad of casters, was a huge mothering horizontal 'I' beam running U/S - D/S.
These two beams formed the flying portion of the 'drawer slides'.
The mansion formed the drawer.
Opening and closing the 'drawer' allowed the mansion to track U/S - D/S whether in the air or, seemingly, on the deck.
Flying the 'drawer slides' flew the mansion.

The mansion was pretty massive, not only in weight but in height, width and U/S - D/S depth as well.
When the mansion was flown U/S and out to it's high trim, it occupied so much of the stage tower that it contained elements of several LX pipes underneath it within it's raked floor.

Rigging was by the fine lads from Feller Precision.

The mansion flew with the motivation of a redundant pair of hydraulic motors driving either end of a common drive shaft through a matching pair of planetary gearsets.
The drive shaft was USC essentially serving as the 'idler block' for the mansion's counter-weights.
The 'line lock', as it were, was a single disc brake in the neighbourhood of 3' in diameter near the centre of the 'idler shaft' with a redundant pair of hydraulically actuated calipers.

Since you saw the show, you know the mansion flew in and out complete with cast and crew on board.

The 1st National U.S. touring mansion was a pretty good trick too but nowhere near the scale of the permanent rigs.

Sorry to have droned on and, again, thanks for the memories!

Toodleoo!
Ron Hebbard