Bulldog OAR

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Apr 29, 2012
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I have been working on this OAR (Offset Ascending Rack). It slips on the line mid-line by swiveling the link pins up, wrapping the rope around the pins, and through the swing arms. A neat feature of this swivel link spine, is that the OAR will tend slack in the normal manner. The top attach point pictured has a split ring, but a clevis can just as easily be fastened there also.
102_1591.jpg


Here is a short video clip showing its function. (Credit to my younges son for filming the clip)
http://www.youtube.com/watch?v=5TcgfUGZUeo
 
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  • #2
The OAR now has an adjustable attach point which allows for fine tuning of the grip of the OAR by tightening or loosening the brass thumb nut.
DSCN0137_zps7c1d0344.jpg
 
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  • #4
Yes, I am quite stoked about this. It self tails beautifully DdRT with a smaller dia. rope (KMIII) and yet the arms clamp upwards with any application of the climbers weigh due to the outboard anchor point. Plus it tends slack by pulling upwards with the tail also, if desired.
 
Gordon, have you break-tested any? It looks like it has a number of little retainer clips on the side. How hard are those to bump off?
 
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  • #7
I have not done any break tests with this one. I did some drop testing with an earlier version with good result, under substantial shock load it will allow some slippage. The links which make up the spine are ANSI rated at over 14,000 lbs. The clips will come off with the help of a pair of pliers, but not too easily. The clevis could be permanently affixed at the bottom attach point, but red locktite is very effective also.
 
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  • #9
It does indeed work SRT. In fact with the fatter, denser rope such as the Yale XTC pictured, you do not really need an adjustable anchor point at all. It will release SRT with this rope by pulling all the way down on the bottom arm and then reaching up with a finger and pulling partly down on the middle arm also. The fatter rope is a snug fit. I would recommend a 7/16 rope for the OAR.
 
For some reason I cant watch the video unless its embedded???

<iframe width="420" height="315" src="http://www.youtube.com/embed/5TcgfUGZUeo" frameborder="0" allowfullscreen></iframe>
 
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  • #13
It may not be as pretty as a ZZZZZZZZZZ : ), but it is just as effective. Works on a doubled rope. Mid line attachable. Much less sitback than a ZZ, and adjustable to boot!

001-13_zps62e5abf6.jpg
 
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