Shear strength and rear seat mounting

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Shear strength and rear seat mounting

Postby BNC04 » Thu May 09, 2013 5:03 am

Recently purchased a trailmax fold and tumble seat and am toying with an idea to install it using a track system from MACS which might work but before I go too far I wanted to ask about the strength.
The studs that I'm looking at would allow for ease of removing are rated for a shear strength of 2000lbs lateral. There would be 4 studs in use. Is this strong enough for a rear seat application in case of an accident?
http://www.macscustomtiedowns.com/category/VersaTie

I was planning on using 4 3/8" grade 8 bolts through the bed with large flat washers for backing but like to idea of quick removal and tie down capability of the MAC system if it will be safe enough.


Thanks
Brett
75 D44/ARB/Disc PS. 86 5.0 Carbed- NP-435 yukon rear. 4.11 3.5 Susp lift Rampage top
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Re: Shear strength and rear seat mounting

Postby Kinder » Thu May 09, 2013 5:16 am

The bolts and brackets are strong enough, though I'm not a safety engineer, your problem is the mounting. The factory positions are reinforced with a thicker than sheet metal channel & large welded nuts. By just bolting through the sheet metal you are running the risk off pulling the hardware right through the sheet metal if a major force was applied. I'd try two options; use the factory mounting holes or recreate the strength in the new mounting locations.
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Re: Shear strength and rear seat mounting

Postby BNC04 » Thu May 09, 2013 5:25 am

kinder wrote:The bolts and brackets are strong enough, though I'm not a safety engineer, your problem is the mounting. The factory positions are reinforced with a thicker than sheet metal channel & large welded nuts. By just bolting through the sheet metal you are running the risk off pulling the hardware right through the sheet metal if a major force was applied. I'd try two options; use the factory mounting holes or recreate the strength in the new mounting locations.


Thanks Kinder, If I go this route, I plan on using some plate or large washers underneath to increase the thickness and spread the load.

Brett
75 D44/ARB/Disc PS. 86 5.0 Carbed- NP-435 yukon rear. 4.11 3.5 Susp lift Rampage top
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Re: Shear strength and rear seat mounting

Postby BNC04 » Thu May 09, 2013 6:16 pm

Thanks all, I ordered up a set of tracks and mounting studs. Pretty cool place, good customer service. I called this afternoon at 3:00 and the parts have shipped via Fedx already.
Brett
75 D44/ARB/Disc PS. 86 5.0 Carbed- NP-435 yukon rear. 4.11 3.5 Susp lift Rampage top
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Re: Shear strength and rear seat mounting

Postby Jesus_man » Fri May 10, 2013 3:17 am

Do post pictures! I wouldn't mind having something like that too. A 2 minute operation to install or remove the rear seat!
1973 Bronco, 351 SEFI, Locked, discs, 35's ZF-5spd and Atlas 4spd. 235:1 Crawl Ratio. It may be ugly, but it's slow.
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Re: Shear strength and rear seat mounting

Postby kcfeist » Sat May 11, 2013 8:57 pm

I would think in an accident the bolts only hold the mass of the seat. The belts are what need to hold passengers.
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