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Author Topic: Spanset Rigging  (Read 12582 times)

Brian Wynn

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Re: Spanset Rigging
« Reply #10 on: January 05, 2015, 08:16:30 pm »

This is what I do.
Of course I had to custom make my frames to make it happen.
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Brian Wynn

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Re: Spanset Rigging
« Reply #11 on: January 05, 2015, 08:17:13 pm »

Option 2
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Mark Cadwallader

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Re: Spanset Rigging
« Reply #12 on: January 05, 2015, 09:50:52 pm »

OP:  Disclaimer: I am not a professional rigger. You should consult with a professional rigger to find out how to properly do this rigging. People die from faulty rigging.

That said, if you take a loop of string and hang it over two of your your spread fingers, you will probably see how the loop can wrap around the ends of your fingers. Once you do that pull on the bottom of the loop. You will see how that tries to bring your fingers (forks of the lift) together.  That should give you an idea of the forces involved, and why you need to talk to a rigger (and maybe an engineer, too).

Mark C.
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Xavier Moore

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Re: Spanset Rigging
« Reply #13 on: January 06, 2015, 02:23:33 pm »

I don't know if the Sumners are OK with side loading. I called Genie a while back and sideways loads on the ST towers are not rated. So instead you'd want something across the forks to provide a center hang point, or maybe just a spacer to keep the forks from being pulled toward each other.

i could use a spacer its just that sumner does make anything like that. what i was going to attempt was to buy 2 of sumners hook blocks(pitcure below)remove the hooks and then go to a welder and have him weld the two pieces together with a piece of steel in the middle. so that i could use that as the strain so the the forks do collapse.

i wouldnt need the hooks on the hook blocks because carvins fly bar is desiged to be hung from the center.

Or if someone could direct me to a company that already has a spacer the would fit the sumner lift
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Xavier Moore

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Re: Spanset Rigging
« Reply #14 on: January 06, 2015, 02:24:55 pm »

We use a spacer made from 2.5" square steel tubing.  It's only to keep the forks from being pulled together and is not designed to suspend any load.

did you have those spacers made or did you buy them from a company.
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Milt Hathaway

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Re: Spanset Rigging
« Reply #15 on: January 06, 2015, 02:51:14 pm »

i could use a spacer its just that sumner does make anything like that. what i was going to attempt was to buy 2 of sumners hook blocks(pitcure below)remove the hooks and then go to a welder and have him weld the two pieces together with a piece of steel in the middle. so that i could use that as the strain so the the forks do collapse.

i wouldnt need the hooks on the hook blocks because carvins fly bar is desiged to be hung from the center.

Or if someone could direct me to a company that already has a spacer the would fit the sumner lift

Or you can use a spreader bar like this (just invert it for your application): http://www.globalindustrial.com/p/material-handling/hoists-cranes/lifting-spreader-beams/12-48-economy-lift-beam-adjustable-length-1000-lb-capacity

(Be aware that this particular spreader may not meet your load and fork spacing requirements. Shop carefully.)

Hang it from Sumner's hook blocks, rig your array from the center point, and not only is it safer but you've also gained slightly over a foot in array height.

Note: If you're having something custom built it could sit on top of the forks with some method to secure it. You gain even more safety and height that way.
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Dave Barker

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Re: Spanset Rigging
« Reply #16 on: January 06, 2015, 03:44:34 pm »

I have a set of Sumner 20's and this is what I do.  I use a pair of the Light Source fork adaptors and a half clamp and use a piece of sch 40 pipe between.  Then hang the line array with a 3' steel spanset down to the shackle on the bumper. All of the weight is on top of the forks.  The fork adaptors allow adjustment to keep the weight back as far as I can based on array bumper depth and there is a set screw to tighten the fork adaptors down.  I also keep the forks "flipped" in so the space between the fork is minimal. I had the pipe threaded on both ends and installed couplers on each end so there is no chance the pipe could slide through the half clamp, not sure that it ever would but it makes me feel better!
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Riley Casey

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Re: Spanset Rigging
« Reply #17 on: January 06, 2015, 03:51:38 pm »

I just ordered another set of these frames.  The tubing is 2.5" steel, the cross section required to fit over the forks of our older Genies.  This is drawn upside down as the long bar actually sits on top of the forks.  They have half inch forged eyebolts in the center and near the ends for lifting up to 500 lbs.  Holes in the short sections match holes in the forks to accept quick release pins.  I strongly suggest consulting an experienced rigger BEFORE you buy and implement anything that you hang over peoples' heads.

Mike Pyle

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Re: Spanset Rigging
« Reply #18 on: January 06, 2015, 04:47:43 pm »

Polar Focus used to make the GK kits for Genie Lifts. They still show some model numbers on their site but no images. The kits might fit the Sumner lifts, I don't know.
http://www.polarfocus.com/catalog/species/84/#species-header

I sell VMB lifts and the Cosmic Truss CT-5 which is very similar, possibly oem'ed by VMB. They offer welded cross bars  to fit the forks on their models, which I believe someone posted images of earlier in the thread.
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Xavier Moore

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Re: Spanset Rigging
« Reply #19 on: January 06, 2015, 04:53:26 pm »

I have a set of Sumner 20's and this is what I do.  I use a pair of the Light Source fork adaptors and a half clamp and use a piece of sch 40 pipe between.  Then hang the line array with a 3' steel spanset down to the shackle on the bumper. All of the weight is on top of the forks.  The fork adaptors allow adjustment to keep the weight back as far as I can based on array bumper depth and there is a set screw to tighten the fork adaptors down.  I also keep the forks "flipped" in so the space between the fork is minimal. I had the pipe threaded on both ends and installed couplers on each end so there is no chance the pipe could slide through the half clamp, not sure that it ever would but it makes me feel better!

how are you able to determine the ammount of weight you can put on the schedule 40 pipe
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