Scott,
Gorilla (urethane) glue will fill a gap, but that gap consists of
foam and will have reduced strength. Joints must be clamped or receive
pressure from nailing, or stapling until completely cured. If you just
press two surfaces together to cure as you might do with T-88, the
foaming action of the urethane glue will push them apart. Gloves are
recommended--I don't think the glue is toxic, but it will leave your skin
stained brown if not wiped clean immediately with a solvent. The other
thing I have found is that it is even sneakier than epoxy at getting onto
everything. Excess glue squeezed from the joints is easily removed with
a chisel after curing as it just consists of foam. I purchase this glue
in small containers even though it is more expensive that way. A little
bit goes a long way and it tends to harden in the container after a few
months. I have done a lot of experimenting with this glue in cabinet
making and aircraft application. I am not yet confident enough in it to
use it on a primary aircraft structure like the spar on a KR.
I tried making some top bows for the fuselage on a Pietenpol
using Gorilla Glue. I apparently did not get even pressure throughout
the length of the bows and they failed miserably. I have used the same
setup for making them with West System epoxy and they came out fine. I
would recommend making some test bows first with cheap wood.
Rich Hartwig
Waunakee, WI
Hartwig@Juno
