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Re: FW: Exotic Wood Question

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Has anyone done work with bamboo? I imagine it has a limited scope of
applications, but it has some great properties. Just curious to find out
if there is a good application out there (other than traditional uses of
bamboo in its natural cylindrical form).

Vertical laminations seem like a good idea for this project, since cost
and other factors in larger beams really aren't issues.

Is the goal to simply support the weight, or are there additional prizes
(i.e. for having the stiffest beam)? Also, are those numbers correct?
Supporting ~33lbs over ~1' span and a deflection limit of ~L/18 doesn't
seem like it requires much engineering.

>-----Original Message-----
>From: Daryl Richardson [mailto:h.d.richardson(--nospam--at)] 
>Sent: Wednesday, December 29, 2004 1:25 PM
>To: seaint(--nospam--at)
>Subject: Re: Exotic Wood Question
> Time, hence availability, may be against you. If so you might consider
flooring hardwoods such as maple, oak or ash.
> If there are no limitations consider greenheart. We used two
triangular prisms of that for bearings for load testing a 4x4 beam for
demonstration testing in a structural lab many years ago. It was too
heavy to float and too hard to cut with woodworking tools. It may also
be too expensive or too scarce for your purposes.
>H. Daryl Richardson
>----- Original Message ----- 
>From: Caldwell, Stan 
>To: SEAINT Listserv 
>Sent: Wednesday, December 29, 2004 9:35 AM
>Subject: Exotic Wood Question
>I am writing on behalf of my nephew, Jake, who is in the eighth grade.
He is participating in a science olympiad and needs to fabricate a
laminated wood beam and load test it. According to Jake, the beam must
span 350 mm (13.78") and be no higher than 40 mm (1.57") and no wider
than 20 mm (0.79"). It must be a straight, solid rectangular section
fabricated from strips of wood no thicker than 3.175 mm (0.125"), glue,
and nothing else. Finally, it must support a center load of 15 Kg
(33.1#) with a deflection less than 20 mm (0.79").
>I am thinking that the winning beam will be fabricated from wood that
is dense and very fine-grained, without knots or other irregularities.
In other words, an exotic hardwood from South America or Asia, like Pau
Lope or Teak, rather than good old Southern Pine or Douglas Fir. The
wood must be available in Dallas, or available online with delivery
within the next two weeks. Of course, such woods do not appear in NDS,
so I have very limited information on them. Also, I am thinking that the
laminations should be vertical, rather than horizontal. This should make
a stronger beam, and make the glue choice less important. 
>1] What wood species do you recommend? What are its mechanical
>2] Do you concur with vertical laminations?
>Thanks in advance for your thoughts.
>Stan R. Caldwell, P.E.
>Vice President
>8616 Northwest Plaza Drive
>=== message truncated ===