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Re: multiple layers stronger than one
By:Mark Kanzler
Date: 3/6/1998, 2:14 pm
In Response To: Re: multiple layers stronger than one (Rob Cochrane)

Safety margins in aerospace are typically smaller than 100% I think we're using 1.5 as a factor of safety. 2.0 should be adequate for kayaks, provided that loads are given on the high (conservative) end of the spectrum.

> Hi All,

> George, If I remember you weigh about 135lbs, I weigh 115Kg that
> is almost double your weight, Fred Bloggs weighs 185lbs and Alan 203lbs,
> and so on. When I paddle I take my lunch, or a weeks supply or a months
> supply of food clothing etc. etc.

> Now if I were to engineer a boat to have a safety margin of 100%
> and I loaded this to the hilt with a range of additional brown bottles
> for the week end and those famous steaks etc. etc and the thing broke
> on the way I would be pis........ not happy. So as with most engineering
> one looks to 300 to 500% safety factor.

> Now if you paddle in a smooth pond with no wind and no waves
> then 28 to 30 lbs on a 16ft stripper is fine but in my opinion it
> would not stand the test of time in 30knot winds and a 4 ft chop let
> alone a hard landing in some mean 16ft surf.

> That is my humble opinion

> All the best Rob

Messages In This Thread

Re: multiple layers stronger than one
Rob Cochrane -- 11/22/1997, 6:12 pm
Re: multiple layers stronger than one
Mark Kanzler -- 3/6/1998, 2:14 pm