Re: What I learned from Sebastian

The main problem with cyano joints is that, certainly with balsa, it appears to have no shock load resistance. The joints are liable to fail if the glider dives onto a hard surface.

Bob

On Feb 19 2013, William Gowen wrote:

Sebastian Perez is a local high school student involved in several Science
Olympiad events. Sebastian worked all day today to finish his second glider
for the SO elastic launched glider event. I have often assured him that the
only glue that would work for gluing the foam flaps onto a WIF7 wing is
epoxy. Somewhere toward the end of the day (and after many messy and time
consuming epoxy applications) he decided that he wanted to do an experiment
to see exactly what CA would do to Durobatics foam. I gave him the thin CA
thinking that would burn a hole thru the foam the quickest. He poured some
on the foam and said "nothing's happening". So I said that maybe the
problem was that CA wouldn't stick to the foam. We both wanted to find out
so I took a piece of balsa and a piece of foam and glued them together with
a thin film of thick CA. A few seconds later they seemed to be stuck when I
pulled on the foam, so I decided to see how hard it would be to pull them
apart. The result was that the foam split diagonally, leaving a strip of
foam glued to the full length of the balsa. My next glider won't have any
epoxy!

Oh yeah - 2 weeks ago Sebastian set new Sr. Cat 1 AMA records in SCLG and
UCLG using his first glider and on his first day flying it.