"Bart" wrote in message
...
I know I haven't posted in here in about forever, and I'm (sadly) no
further along in this project than the "gathered most materials, still
doing last-minute-design" stage, but I need to ask a couple plywood
questions:

First, I'm guessing that marine plywood was used in the construction
of the Marcos line of cars because it was the best laminate wood
material available at the time (early '60s). The car I'm building will
be very much like the Marcos, in that it will be a multiple "stressed
box" semi-monocoque structure bonded at the sills and front and rear
bulkheads to the open-cockpit fiberglass body I'm using. In the year
2008, is there a another grade of plywood besides "marine" that will
do as well? The entire 1/2" ply bottom of the car will be epoxy-sealed
against moisture and rubberized for noise absorption.

Second, when you guys build (built?) monocoque small aircraft
structures of the stringer/skin/bulkhead type, what thicknesses of
plywood do you typically use?

Thanks for your kind tolerance!

Bart

Knowing that this subject is a little OT for this group, I took a couple of
extra minutes to don my trusty old asbestos suit. ;-)

I admit that I have long been intrigued by the Marcos wooden cars, and that
I did covet one in my youth. However, I am not at all sure of exactly what
grade, thickness, or ply count of plywood was actually used in their
construction--and I strongly advise that you find out for sure before
attempting to proceed. Even if it was "marine plywood", which I think that
I may have heard at some point, I believe that the term "marine" only
specifies that the glue between the plies is not water soluble; so an
acceptable grade of plywood may not be as close as your nearest "Borg".

I was curious enough to take a quick look, but did not find any usefull
specifications. However, here a couple of Marcos Owners Club links:
http://www.marcos-oc.com/
http://www.clubmarcos.net/Links.aspx

BTW, I've always wondered what they did to keep the nearest portions of the
wood work safe from the heat of the exhaust--and, of course, my curiosity
remains unsatisfied.

Peter