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Re: S&G: Stiffness
By:Malcolm Schweizer
Date: 6/26/2013, 9:42 pm
In Response To: Re: S&G: Stiffness (JohnAbercrombie)

I just rethought this, and I had been looking at the point of failure column but really needed to look at the deflection column. So plywood was much more flexy than strips. That is what I had hypothesized due to grain structure and the varying grain of each strip working in unison as opposed to five or six layers of flat sawn grain which has less resistance on the flat plane. I would suggest that if tested the other direction- on edge- the results would be opposite with plywood being less flexy.

Now, here is where it gets fun for Mr. Caouette- the answer to his question about flexiness of ply versus strip would in part depend on the shape of the hull and how vertical the side panels are as well as the proportion of vertical (or near-vertical) panels to flat (horizontal) panels. A Queen Charlotte with steep sides may lend better to plywood whereas a Disco Bay might be the other way around in terms of which flexes more with which material. I am hypothesizing here- open to discussion. ...but I am always right and never wrong. I also never tell a lie. ;-)

This is the stuff I love. I really don't know why I love it. It's like a puzzle or riddle that you have to figure out.

Messages In This Thread

S&G: Stiffness
MattD. -- 6/26/2013, 1:49 pm
Re: S&G: Stiffness
Malcolm Schweizer -- 6/26/2013, 2:07 pm
Re: S&G: Stiffness
JohnAbercrombie -- 6/26/2013, 2:46 pm
Re: S&G: Stiffness
Malcolm Schweizer -- 6/26/2013, 9:42 pm
Re: S&G: Stiffness
john Messinger -- 6/27/2013, 8:44 am
Re: S&G: Stiffness
john Messinger -- 6/27/2013, 8:57 am