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  #1  
Old 05-09-2006, 02:49 PM
JMHawkins JMHawkins is offline
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Join Date: Nov 2005
Posts: 7
Default Brummels vs Grommets in HM line

Hello all,

A question about splicing HM line (Amsteel). I need to span a short distance with eyes on each end (ring hitches actually). Iím considering two different constructions, and wondered if there was a significant difference in strength between a simple grommet with 72x diameter tail bury, or McDonald Brummels on each end with only a 12x tail bury (e.g. probably not enough tail bury to contribute to the strength). I like the look of the brummels better than the grommet, but I wonít have room to do anything other than a cosmetic tail bury. Am I asking for trouble? Or is the ring-hitch costing me more strength than the brummel farther down the line?

Thank you,
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  #2  
Old 05-09-2006, 09:33 PM
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Hi there,

there might be a difference in strength between the two constructions of your strop, but amsteel is so so strong - if you were worried about breaking the stuff, splicing and ring hitches probably wouldn't be the best route to take in the first place ... for what it's worth, we regularly make up little mainsheet boom strops for Folkboats and Knarrs and other little one designs and we usually make them of, say, 3/16 or 1/4 spectra (sized for feel and durability more than anything), a double brummell splice on either end, tail buries overlapped, finished length 12-18 inches. These replace strops previously made of 7x19 wire nicopressed at each end. The double splice route is neater than the grommet and is pretty indestructible. Best of luck.
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  #3  
Old 05-12-2006, 06:19 PM
JMHawkins JMHawkins is offline
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Thanks, I was pretty sure the strength would be okay (I could lift my boat with a couple of these lines), but I was worried about the security of the splice (or knice/splot as Brion says of the brummel). The locked brummel seems like a pretty secure construction - unlikely to creep loose on me.

One thing that I'm still curious about - does a ring hitch significantly weaken HM line the way, say, a bowline would?
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  #4  
Old 05-15-2006, 03:09 PM
Brion Toss Brion Toss is offline
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Default Grommets

Hello,
A locked Brummel grommet will test at somewhat less than 200% of the rope strength; loss comes from the ring hitches, and from the expansion of the rope, but it's not a huge loss. I'd rather do this than the two splices mentioned above, but either will work.
We have also begun making "Yippee Sling" grommets, which are unlocked, so need obsessive stitching, for relatively light duty things like small boat tack and head pendants. You can adjust these to get the ideal height before either stitching or replacing with a Brummeled grommet.
Fair leads,
Brion Toss
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