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Tvash
climber
Seattle
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This is the closest I'll ever get to being a rock star.
BTW, I've got a BSME from Cal, but no PE license.
If it explodes, I don't exist ;)
It won't, though.
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Banquo
climber
Amerricka
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The Chicago 1/2" is only rated to 2400 lbs - and derated to 2280 due to the angle. I think you read the wrong rating number on the table. This gives you only a 6:1 safety factor. Bump it up to 9/16" for 7:1.
One Chicago catalog I looked at rated the 1/2" for 2600 lbs straight and 650 lbs at 45 degrees.
http://www.chicagohardware.com/catalog/18_22_eyebolts.pdf
Another states 2200 lbs
http://www.chicagohardware.com/catalog/14_15_eyebolts.pdf
The second one also states that "Loads are based on a safety factor of 5 to 1." so there is no need to apply additional safety factors unless you are lifting people when, if I recall OSHA right, it should be 7:1.
Be sure to get quicklinks and bolts from reputable suppliers as there is a lot of Chinese junk coming into the country. I wouldn't be surprised to find Chinese knockoffs claiming to be Chicago USA.
I also have an MS in Civil Engineering. I do have a PE and I also taught structural engineering at a university for 30 years.
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overwatch
climber
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I work as an event high rigger and I have been following this thread but have hesitated to comment without knowing the structure you're hanging in. Is there some sort of extreme trim height issue that disallows you from bridling from adjacent beams?
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ionlyski
Trad climber
Kalispell, Montana
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Thanks Banquo and others. The angle on these shoulder bolts, which are aligned to take maximum advantage of the shoulder is probably more like 10 degrees and I can lessen that with longer bridles too.
Overwatch, yes extreme trim height is one of my reasons for this project. The other is to achieve front and back motor points from one beam, otherwise it's a pain in the asss to tether the array. And actually the beams are 20 feet apart from each other with zero rigging options in between. Bridling between beams wouldn't be an option.
Look, the two venues I will use these in are for events with MUCH smaller arrays than my outdoor photo above. In one, I can't even lift with motors due to low trim, so for years we've had to lift with Genies and dead hang right up to the beam. That one in particular uses 4 Vertec boxes per array totaling 500 lbs including motors at 250 per point.
Arne
Edit-And yes Banquo as I've always understood it Safe Working Loads which are stamped to the hardware are 5:1 above breaking strength.
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overwatch
climber
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understood thanks for the reply
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Handjam Belay
Gym climber
expat from the truth
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This whole thing took a turn into the 4th level of Hell when you said you were an audio guy.
We enter the 5 level of Hell when you add the outdoor roof structure.
Buy a roll of trickline and focus your cabinets that way.
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ionlyski
Trad climber
Kalispell, Montana
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Change yer hand jammy mitts.
You're greasing off.
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