So there's been a lot of talk on this thread about overloading components on one line set. My idea was to basically make a big 'x' frame that can get u bolted onto 2 distant arbors solely to synchronize their travel. Obviously, what that frame looks like would vary depending on the existing fly system. You'd had to build it out in front of the other operating lines and clear whatever structure may get in the way... Each arbor would be loaded appropriately for the weight on each pipe. In my mind, this would ensure that 2 operators don't vary their travel speed/acceleration relative to each other and keep the flown unit, that's hung on 2 pipes, stable as it flies in out (no rocking US/DS). Granted, whatever the "x frame" is will have some play in it, depending on how its constructed, but it'll stop a big lurch from happening in the flown unit when one operator sneezes or his hand slips on the line or something...

More of a thought experiment at this point, just wanted to see if there was a method for this, other than telling 2 ops to practice the move a lot and do a mind meld to make the fly smooth....
 
I would think you could link the two arbors with wire rope and blocks more safely. That moving x frame sounds fraught with problems, especially if more than a few sets apart. So likely to put lateral forces on the arbors that the whole system is assuredly not designed for.
 
I think you’re in the territory of winches and chain hoists. I just don’t think non-adjacent linesets can be safely married without some intense engineering. Basically to do what you want a lot of custom configuring would need to be done to your grid. We do that where I work, but we are also a big regional with a multi million dollar budget so we can afford to re-rig for show specific moves.
 
Reread things. This seems not to be weight, but coordination. It seems the set piece means the intervening sets are not in use. The right way would be to re-rig one set. Remove batten and re-reeve lines to pick up the piece at its corners. Or if you a have walk on gridiron just rig a pot line system for the piece.
 
Reread things. This seems not to be weight, but coordination. It seems the set piece means the intervening sets are not in use. The right way would be to re-rig one set. Remove batten and re-reeve lines to pick up the piece at its corners. Or if you a have walk on gridiron just rig a pot line system for the piece.

That’s the direction I’m thinking as well. Stock up on mule blocks!
 
yeah that does seem to be the way to go. 1 arbor, 4 lines off the clew routed to wherever the corners of the unit are.

Thanks for the input, the problem seems solved
 
Good Morning all

I dont consider myself a Rigger and I know his is just a hypithetical discussion but it sounds to me like 4 small chain motors would solve the sync issue.
yes, I know it may not be in the budget.
jumping 4 arbor sounds scary to me as well
 
Good Morning all

I dont consider myself a Rigger and I know his is just a hypithetical discussion but it sounds to me like 4 small chain motors would solve the sync issue.
yes, I know it may not be in the budget.
jumping 4 arbor sounds scary to me as well

There's more than one way to skin a cat... But while motors can sound ideal, they present different issues to deal with. So, not a wrong idea, just a different one
 
There's more than one way to skin a cat... But while motors can sound ideal, they present different issues to deal with. So, not a wrong idea, just a different one
@bobgaggle @Jack Hochberg
Since we're still kicking this around; four motors are noisy.
Another method is to install blocks, sheaves if you will, at the bottom and top of the two arbors being married then install cable to link the two arbors together such that neither can move without the other. You can still have at least two fly-persons pulling to overcome friction and drag. Also, it's clearly best not to be using the line-sets in between and have them all parked with their battens at the grid and their arbors on their lower end of travel stops. I naively thought we'd flogged this one to death.
Toodleoo!
Ron Hebbard.
 
There's more than one way to skin a cat... But while motors can sound ideal, they present different issues to deal with. So, not a wrong idea, just a different one


Good Morning

I come from the Arena World so motor noise isn't the first thing that comes to mind 8P
I know there are silent systems but that's another issue.

TY
 
First, marry at the arbors is the correct idea. Let each arbor be properly balanced for the load on it’s pipe.
Next think of the way a parallel bar on a drafting table works. This may be an unknown term to some of those who have grown up with some form of auto cad as the only way to produce shop drawings. For those who have never seen (or heard of) a parallel bar was a long horizontal straight edge on a drafting table that replaced the “T” square and could be moved up or down the table and the edge always remained precisely parallel. This was accomplished by a thin cable (usually about 1/32” dis) that was anchored at one corner and then up and down each side of the table around miniature shives and across the table under or inside the bar. The cable was rigged such that pushing up on one end of the bar, pulled up on the other end. Pushing up or down on the bar caused the entire 24” to 36” or longer, bar to move while staying perfectly parallel.

Long story short. Rig a 1/4 cable and a few shieves between the arbors in the same manner. Still use two balanced arbors and two operators but allow the parallel rigging to keep the line sets operating in unison.
 
I still think 4 spotted blocks and one arbor is best. I thought about what Michael suggested but it does require no outrigger supports or other framing intervening, and no blocks attached to arbors. What Ron said and I suggest previously is probably the safest marrying approach for non adjacent arbors. And I think one person could run it, leaving other lock open.
 
Maybe renting some mechanized spot line hoists that can be sync controlled would be an alternative? How much does the jail cell weigh, anyway?
 

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