Scusate per il risveglio di un thread vecchio e sepolto, ma mi sembrava piu' sensato postare qua che aprirne un'altro.
La differenza principale tra l'hysol 9462 e la resina di schaller credo sia che l'hysol 9462 e' tixotropico (non cola), mentre la resina, per definizione sul sito stesso, e' "molto fluida". Ovviamente non e' che una sia meglio dell'altra per questa caratteristica, ma hanno applicazioni diverse.
Posto un'analisi di 2 colle simili, l'hysol 9462 e l'hysol E-120HP che ho scritto su RCU, sperando che interessi a qualcuno e che, magari, qualcuno possa aggiungerci qualcosa di utile e/o darmi delucidazioni in merito. Scusate l'inglese ma nn ho voglia di tradurla... Se non capite qualcosa chiedete pure.
I took a look at the technical sheets for the 2 products:
http://65.213.72.112/tds5/docs/HYSAE-120HP-EN.PDF
and
http://65.213.72.112/tds5/docs/HYSA9462-EN.PDF
Honestly, I can't see the reason why everybody is in love with 9462 and nobody mentions the E-120HP.
Specifically:
Loctite® Hysol® 9462 is a toughened, two component epoxy
adhesive formulated for a good balance of shear and peel properties
in an easy to use, smooth paste. Its medium viscosity, 1:1 ratio and
non-sag features make it easy to apply.
.vs.
LOCTITE Hysol E-120HP is a high viscosity, non-sagging
industrial grade epoxy adhesive with extended work life. Once
mixed, the two component epoxy cures at room temperature to
form a tough, amber-beige bondline with excellent resistance
to peel and impact forces. When fully cured, the epoxy offers
superior thermal shock resistance, excellent mechanical and
electrical properties, and withstands exposure to a wide variety
of solvents and chemicals. Typical applications
include bonding nose cones in aerospace applications. It is
also suitable for low stress, general industrial applications
which require high impact and high peel strength. Bonds
dissimilar materials including aluminum, steel, and other
metals, as well as a variety of plastics and ceramics.
It doesn't mention wood, but later on (lap shearing strength):
Wood (Fir) N/mm² 11.3 (psi) (1,600)
The data sheet for the 9462 has no similar infos for wood, but comparing etched aluminum figures we can see that:
77F - 3500 psi
180F - 600 psi
250F - 150 psi
Equivalents for the E-120HP are about
:
77F - 2000 psi
180F - 1500 psi
250F - 500 psi
Now, I don't know the exact curve describing the gap between 77F and 180F, but it seems to me the 9462's shearing strength decreases very steeply with temperature, while the E-120HP decreases in a much milder way. Also, I used the worst case figures for etched aluminum: it is enough to abrade the surface a little and the initial strength for the E-120HP raises to a whole 4800 psi, which is way over the 3500 psi for the 9462.
Considering we sometimes leave our airplanes exposed under direct sunlight for a while, the internal temperature can raise significantly, potentially lowering the strength of the glue.
Not mentioning E-120HP actually maintains or even improves its strength over time, as long as not exposed to salt or water/humidity, even when exposed to fuel.
All this is not to bash 9462 or to promote E-120HP, I could care less, all I want to know is why is 9462 perceived as "the best glue you'll ever get" and nobody seems to have ever mentioned E-120HP? Reading this thread also sounds like people consider it a lower grade compont: why?
Ciao.