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Re: multiple layers stronger than one
By:Rob Cochrane
Date: 11/21/1997, 1:37 pm

Hi All & George,

Not realy trying to skirt the question rather trying not to write a four page chapter!!

As I said the point loading is a rule of thumb, an aid to design!! if you will. The costs involved in undertaking a full analysis are prohibitive as I do not have the software capable of undertaking complex composite analysis. And I am to old and to tired to do it by hand.

The weight is what I call standard sea expidition. We are not called the Skeleton Coast for nothing. Our sea conditions can be of the worst in the Atlantic and the last thing I want is a two piece Kayak at sea. Especialy if I am in the thing. If I were setting up for a lake or sheltered bay I could reduce to perhaps 14 to 16Kg. This by the way is 19foot by 24 inches.

I have unpacked my vacume pump again to do some tests on multiple layers. I will try to spend Sunday setting up some test pieces and then on Monday trundle off to the local lab to do the green tests. The balance will have to weight two weeks.

The form I will use is 4mm BS approved Ply 300mm long 50mm wide as the sub strate.

Then I will use various combinations of 135g 165g 250g 450g cloth and 450g bi axial and 450g tri axial glass. I will try to get to the optimum resin cloth balance by using a peel ply and bleeder assembly.

I will use WEST 105 206 resin as well as 105 205 (that is all I can get).

Many years ago I did a similar test with prepregs we were getting delamination problems with and for the life of me I could not find my notes. Two rooms of boxes now a total mess.

George, I am all for trying to reduce weight as much as possible. However, I must temper the radical side of me to provide to my clients who may either purchase a design or Kayak or other boat for that matter that is capable of taking the conditions without my control in manufacture or if manufactured by me then of a level that will allow me to sleep at night.

My other love and project then we can push the limits, Speed sailing and world records are not for this forum.

All the best Rob

Messages In This Thread

Re: multiple layers stronger than one
Rob Cochrane -- 11/21/1997, 1:37 pm