Message-Id: <199705011357.GAA28610@ns1.intelenet.net>
From: Wolfgang Brinck <wolfgang.brinck@hksystems.com>
Subject: Re: gunwale
To: baidarka@lists.intelenet.net
Date: Thu, 1 May 97 8:56:28 CDT
In-Reply-To: <3.0.1.32.19970430161012.006b2630@skypoint.com>; from "wayne steffens" at Apr 30, 97 4:10 pm
>
> How important is the 1.75 inch dimension on a gunwale (following Brinck).
> Can I get by with clear 1.5 x.75 inch hemlock? Will I need to compensate by
> making it thicker?
>
> Wayne
>
>
I'm glad you recovered my earlier posting on bending of wood. So anyway,
stiffness goes up with the cube of the depth, so
1.75 / 1.5 = 1.17
which is the ratio of depth. Cube that to get the ration of stiffnes
( 1.17 ) ** 3 = 1.6.
Since increasing thickness increases stiffness linearly, you would have
to make the gunwale 1.6 times as thick to have the same stiffness.
Or .75 * 1.6 = 1.2
Or a 1.75 X .75 piece of wood has the same stiffness
as a 1.5 X 1.2 piece of wood.
Or to think of it yet another way, if hemlock was 1.6 times as stiff
as spruce, then you could get away with shallower gunwales, but I
doubt that it is.
--
wolfgang. /|
brinck@h / oo wolf
ksystem / \ wolf
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