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  #1  
Old 04-18-2011, 12:07 PM
tamishel tamishel is offline
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Join Date: Mar 2009
Posts: 6
Default Strength of HMPE grommet?

Hello all,

I'm planning (after I receive my Book 5) to fabricate a grommet/loop/whatever of 1/4" Amsteel to put round my sprit to attach my furling screacher. Boat is an F-27 trimaran, somewhat modified. I expect this thing to see at maximum around 3,000 lb, prolly usually sees 1,500 generally.

I'm sitting here thinking about the fact that there's no possible way to have the 'correct' amount of tail in the loop, given the size.'

Am I crazy to trust this thing?

Thanks in advance,
tami
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  #2  
Old 04-19-2011, 08:11 AM
Brion Toss Brion Toss is offline
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Join Date: Jun 2005
Posts: 1,180
Default Strength

Hi there,
Great question. Yeah, you're right, there's no way to get sufficient friction with the teensy bury of such a short grommet. Fortunately we have mass and cunning on our side. Mass because the material, given a full, overlapped bury, is doubled in the grommet, and the grommet is already something like twice the strength of a straight length of the same material. And cunning because you start with a Mobius Brummel, which not only prevents slippage, but provides some strength, to compensate for the shortage of friction in the bury.
In destruction tests, even very small grommets have lasted to well over 150% of rope strength. So no, you're not crazy. Just do the splice right.
Fair leads,
Brion Toss
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  #3  
Old 04-19-2011, 03:06 PM
tamishel tamishel is offline
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Default

Thanks for the confidence

Do I understand that the book will tell me how I'm supposed to pull the tail through a short curve, because the two Splicing Wands I have sure ain't gonna do it ;-)
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  #4  
Old 04-20-2011, 01:14 PM
tamishel tamishel is offline
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Join Date: Mar 2009
Posts: 6
Default clever man

I just received the book, and yes, the questions are answered.

My compliments on your cleverness, and my thanks for sharing same.
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