Explanation Just Won't Stick
by Robert A. Galganski
Why the struts found with the Roswell debris were not balsa wood.
Rectangular and I-shaped cross-section thin-strut fragments
recovered from the Foster ranch debris field in early July 1947 allegedly displayed
extraordinary physical properties. Persons who handled them said they were extremely
lightweight, slightly flexible but unbreakable, and could not be cut or burned. Roswell
skeptics dismiss these reports, attributing them to the vagaries of long-term memory and
embellished accounts of similar wreckage - specifically, balsa wood sticks-from rawin
radar targets comprising Project Mogul Flight 4.
Former Mogul project engineer Charles B. Moore hinted that specially treated balsa wood
used in those targets may have contributed to the wood misidentification problem. In an
October 31, 1994, People magazine article titled "A SaucerScorned," he indicated
that "the balsa wood was soaked in glue, like Elmer's Glue. It s a casein product [a
protein derived from milk] that just won t burn at all." Moore added that the glue
made the wood "a little bit stiffer and less easy todent than ordinary
Moore also referred to altered balsa-wood characteristics in the 1995 Crystal Sky
Production video, Roswell Remembered, stating that ". . . some of them [the sticks]
appeared to have been stiffened by having something like Elmer's Glueon them."
Curiously, he did not discuss the subject in his most recent and complete recollection of
Project Mogul (Benson Saler, Charles A. Ziegler, and Charles B. Moore, UFO Crash at
Roswell: The Genesis of a Modern Myth, Herndon, Va.: Smithsonian Institution Press,
The glue-treated balsa-wood sticks were also discussed by Kent Jeffrey as part of his
recent 180-degree reversal on the Roswell Incident (Kent Jeffrey, "Roswell Anatomy of
a Myth," MUFON UFO Journal, June 1997, pp.3-17). He speculated that the glue
"would probably have given them a different color than that of raw wood, as well as a
different feel or texture probably to the degree that someone who didn't know them for
what they were, might not recognize them as wood."
In summary, Moore and Jeffrey suggest that balsa wood sticks coated with an Elmer's
Glue like substance were unrecognizable from and stiffer than raw balsa wood, and
noncombustible. The stiffness has been cited by Roswell skeptics to explain why the
thin-strut fragments found on the Foster ranch could not be broken by human hands. I
conducted three series of simple experiments to test the "glue hypothesis." This
article presents my findings.
TEST SPECIMEN SELECTION
Because it s been more than 50 years since the original Project Mogul Flight 4 rawin
radar targets were fabricated, my experiments utilized currently available materials.
Published descriptions and additional information graciously providedby Charles Moore
formed the basis for their selection.
Balsa wood. Ordinary 5/16-inch (8 mm) square balsa-wood sticks available from
any hobby shop were used. Because wood is a natural product, the physical properties of
these sticks were probably similar to the original struts used in rawin target
construction. The first series of experiments was conducted with unmodified (raw) balsa
Glue. Consistent with Moore's recollection, the second series of experiments
utilized balsa-wood sticks coated with Elmer's Glue-All. Afterward, I learned from the
manufacturer Elmer's Products Inc. (a division of Borden, Inc.) that their glue was
introduced in 1947 under the brand name Coscorez. In 1951 its packaging was changed and
the product was renamed for its then-new marketing symbol, Elmer the bull. The glue's
current composition is virtually identical to that of the original 1947 product. Upon
drying, a coating of this white-colored liquid changes into a clear (transparent)
But I also found out that Elmer's Glue is and always was a water-based
polyvinyl-acetate-type adhesive which contains no casein. So Moore's description,
strictly speaking, is contradictory. Consequently, it s not certain whether a casein or a
polyvinyl-acetate glue was used with the 1947 rawin target struts.
To account for both possibilities I ran a third series of experiments which replicated
the others - this time with a casein glue made by the National Casein Company. National
Casein, which has been making casein and resin products since 1919, sent me a sample of
aircraft-grade 8580 Casein Glue, their best product. According to Ken Blake of the company
s New Jersey branch, its strength is comparable to the highest-quality casein glue
available in the mid 1940s. National Casein 8580 Glue is a water-based, ivory-colored
liquid (after mixing - see next section). A surface coated with it has a translucent
appearance when dry.
Material preparation. Moore wasn't sure if the glue was merely brushed on the
sticks or if they were soaked - full-strength or diluted (presumably with water)- in the
glue. For the second (Elmer's Glue) test series I selected an all-glue, full-immersion pan
soak in order to maximize the assumed beneficial effects of the treatment. The specimens
were submerged-individually-in the glue for 20 minutes, removed, and allowed to dry.
Because of some distractions during this time, some sticks stayed in the bath a few
minutes longer than the others.
During my conversation with Ken Blake I learned that a wood s strength isn't influenced
very much by whether or how glue has been applied to it-a full soak or merely brushed on
its surface. Both techniques provide mostly a mechanical attachment of the glue to the
surface of the wood-as with paint; very little glue impregnation occurs. Without pressure
treatment per se-e.g., where a material such as a preservative is literally forced into
the cells of an outdoors-use-type wood-the glue penetrates only several fibers deep below
the surface. (I subsequently evaluated Blake's statement by experiment. See the Beam
Strength and Other Tests section below.) Since I had soaked the Elmer's Glue treated
specimens, I had no choice but to prepare the casein-glue-treated sticks in the same
All of National Casein's glues come in a dry powder form and require mixing with water
according to a specified procedure. These instructions were followed explicitly during
glue preparation. To eliminate the above-noted soak time variability, I immersed all
sticks en masse for 20 minutes in the resulting full-strength liquid product.
After all glue-treated sticks were removed from their bath, their surfaces were brushed
with additional adhesive during the initial drying stage in an attempt to give them a
uniform and drip-free coating. As a result, a relatively thick film covered the
Balsa wood revisited. All raw wood test specimens and those soaked in Elmer's
Glue were purchased in July 1997; they were subsequently employed in the first two series
of experiments performed in early October 1997. The third and final series of tests-those
using casein glue-were conducted in early December and used wood purchased a couple of
weeks earlier. Given the high volume of business the hobby store does, it s possible that
the latter batch of sticks came from a different shipment. Consequently, some of the wood
physical properties such as bending and shear strength could have been different from
those characterizing the earlier group. The extent of such possible disparities-which may
have been well within the envelope of variability normally displayed by all woods-is
COLOR, SURFACE LUSTER, AND TEXTURE
Obviously, raw wood will look and feel different compared to wood that has a coating of
dried glue on it. How much so depends on a number of factors such as the type of wood and
its exposed grain pattern, type of glue used, and the number of coatings applied. When
wet, both adhesive coatings obscured the balsa wood's natural tan color and grain pattern.
But when completely dry its distinguishing characteristics were once again visible. The
Elmer's Glue-treated pieces were shinier and felt smoother than raw wood; their
casein-glue-treated counterparts felt rougher and had a slightly yellow cast and
"frosty" appearance. But in both cases the treated specimens still looked
BEAM STRENGTH AND OTHER TESTS
Since wood has a cellular structure whose outer fibers can absorb liquid, some of its
physical properties can undoubtedly be altered by immersing it in or coating it with glue.
But could a dry, thin shell of glue significantly increase the bending and shear
resistance of balsa wood-an inherently weak material-especially since, as noted earlier,
most of the applied substance merely resides on the surface? The following tests were
performed to provide a quantitative answer to that question.