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<DIV>Balsa is pretty amazing stuff overall, particularly for a natural material. The Xylem that makes up much of the superstructure of any wood (that's what we commonly hear as grain), is essentially a huge number of tubes arrayed side by side, but interconnected along the length. The tubes serve a terrific function in the long direction and the interconnects make the structure have reasonable transverse strength as well. </DIV>
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<DIV>The closest thing manmade that will surpass it in terms of mechanical strength vs flex vs weight vs cost will likely be Buckytube if you excluded the cost. That's just in laboratories now, being made in very small quantities supporting very high end applications. This stuff is the true unobtainium that some have complained about. But that's another subject.</DIV>
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<DIV>There used to be an annual competition in colleges where a very small, known quantity of balsa and glue were used creatively by students to build some kind of support structure like a small bridge. These things would hold unbelievable amounts of weight. </DIV>
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<DIV>Alas, the weakness is shock loading. </DIV>
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<DIV>Matt</DIV> <BR>-----Original Message-----<BR>From: Adam Glatt <adam.g@sasktel.net><BR>To: NSRCA Mailing List <nsrca-discussion@lists.nsrca.org><BR>Sent: Tue, 28 Mar 2006 16:44:02 -0600<BR>Subject: Re: [NSRCA-discussion] An education in balsa usage for pattern<BR><BR>
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<DIV class=AOLPlainTextBody id=AOLMsgPart_0_a3a3b4df-d994-412a-a29e-2c471d7b45f7><PRE><TT>Not directly applicable to pattern, but certainly a good start:
Buy and build a Stevens Aeromodel kit. The planes are small (35-50"
span, 1-2.5lbs) and electric powered. I'm about 1/2 done building the
Edge 540, and am actually enjoying the build because I am constantly in
awe of the genius wood design and its results (consider that this Edge
540 is 40-sized, but will weigh only 2lbs with more performance than all
but the most dedicated 40-sized 3D glow planes).
-Adam
White, Chris wrote:
>
> Can anyone tell me where a person can get a "Crash" course in learning
> about balsa weights and strength and its proper use in balsa pattern
> models.
>
> I notice a few years ago that in the 99 world champs most of the
> Japanese pilots models were balsa and light weight too. It seems that
> everything I read of late seems to indicate that light weight and
> strength only come with composite construction.
>
> Thanks..Chris
>
> ------------------------------------------------------------------------
>
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