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Anchor test

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The budget is a bit streatched  so I have been useing 5/16th quick links for anchors instead of the usual 3/8ths. I know they are pleanty strong but just for reasurance sake I did a little test  over the weekend.

I used a 1/4" quick link made in Malaysa and rated at SWL 880lbs which is roughly 1/2 the SWL of a 5/16th quicklink.
Tied the rope to a tree with single bowline.
Loose coil on ground.
other end of rope has overhand fig 8.
1/4in quick link through loop created by overhand fig eight. Quick link was hand tightened.
Old retired locker w/ broken locking collar attaches 1/4 in quicklink to bumper of F150.
Rope is retired single rope. appears to be  roughly 10.5mm
Mosh accelerator on F150.  When the loose coil runs out and that truck hits the end of the rope you are esentually drop testing with a pickup truck.

The result is the rope breaks at the knott.  The rope always breaks at the knott. If there is a bowline in the system the rope always breaks at the bowline. The next point of breakage will be an overhand on a bight. The rope will only break @ a fig 8 if there is no  bowline or overhand on bight in the system.
 Hard to tell from the photo but the  rope broke in the center of the knott just left of the  broken end.

There has got to be a better place you can save a buck than cheeping out on anchors, Tradman. They may pass your ad hoc testing, but I want extra beef to leave plenty of leeway for variable quality control and wear. Plus, the bigger radius is better for your rope. I can see using 3/8" instead of 1/2 to save money (not to mention carrying the beasts), but 5/16 is cutting it close IMO. I know it is sacrilege, but I would drink one less beer and stick with the bigger ones.


--- Quote from: M_Sprague on September 05, 2012, 08:53:34 am ---.... but I want extra beef to leave plenty of leeway for variable quality control and wear. Plus, the bigger radius is better for your rope.

--- End quote ---
I was thinking along the same line too ....

You could afford better quality gear if you weren't always having to repair your truck from the effects of your hair brained schemes.  The $$$ you spent on gas alone - "moshing the accelerator" - probably would have paid for it.

 The actual bolt inside the sleave of a 3/8ths  5 piece bolt is 5/16ths. I BROKE a 10.5mm rope with a 1/4 in quick link. The 5/16th quick link is rated TWICE  as strong as the 1/4in quick link. That is pleanty of leeway for quality control INMOP. Of course if anyone wants to donate money for my bolt and anchor fund please let me know. I will be happy to take donations 8)
Furthermore I will bet anyone, anytime $1,000 that I can break their dynamic climbing rope with a 5/16ths quicklink and that the break will Not occure at the contact point with the 5/16th radius. You supply the dynamic climbing rope and the $1,000


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