Author Topic: Breaking strain by hand  (Read 10657 times)

KnotNow!

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Re: Breaking strain by hand
« Reply #15 on: July 21, 2005, 08:01:23 PM »
Hi Roo, Sorry about that.  I was trying to IM you and it ended up on forum.  Some times it would be better if I did not post in the late evening ;)
ROY S. CHAPMAN, IGKT-PAB BOARD.

lindsey philpott

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Re: Breaking strain by hand
« Reply #16 on: July 25, 2005, 07:50:43 AM »
Hi Roo,

Composite or not - Hmmm?  Not all composites are made from resins.  I take a rather more composite view (if you'll pardon the pun) that a composite is one in which the material is not pure - such as aluminum or iron or copper or polyester (untreated, of course).  All organic cord is by definition composite in that it is comprised of several different fiber thicknesses from different plants grown under different conditions.  Now that may not accord with your definition, but that is what I referred to.  Not to worry - Roy has it right when he says that all that was wanted was to know what the average Joe could exert.  First, find an average Joe....
After that, all is simple.  Give him (or her!) an average piece of (undefined) cord on an average day in an average climate in an average year of his or her life and you'll have an answer, on average.  A great math teacher once told me that, if I have one foot on the stove (lit, of course) and one foot in the refrigerator (set below freezing of course) on average (assuming I have no protection and no hardened calluses) I'll be comfortable.  I have added nothing to this post and I have taken nothing away, so on average I think it must have evened out!   ;D

squarerigger

Mr average

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Re: Breaking strain by hand
« Reply #17 on: August 21, 2005, 06:09:29 PM »
I weigh 210 lbs and can do pull ups, so my arm strength over limited distances is at least 105 lbs.

I used an old spring sack scale, held the scale in one hand and the hook in the other and pulled.  If my hands started close together I could pull 180 lb but if I started with my hands over 1ft apart this quickly dropped to around 80 lb.

So if logic holds here, providing the cord did not cut my hands, I should be able to static break cord that had a failing point of ca 150 lb (i.e. rated at 30 lb. operational)