hi steve et al.,
let's remember what aluminum does when it oxidizes. bare aluminum in
moist air will form a grayish, NON-CONDUCTIVE oxide. if we want two
pieces of aluminum which are mechanically coupled to be have a good,
solid, reliable electrical coupling as well, then the interface
between the two should be kept from oxidizing. this is not news.
> > On the same page, the manual says "..... and we recommend the use of a
> > mixture of WD40 and graphite powder, or similar material, to lubricate
> > each and every tubing joint surface and screw hole during assembly as
> > well as the end of the element being placed into the boom."
> >
> > Therefore, if I follow the advice of what 99.99% of all hams are
> > telling me (i.e. use Pentrox or similar antioxidant) and what common
> > sense and the laws of physics dictate, I will be in direct violation
> > of the K7LXC Prime Directive! Decisions, decisions.......
>
> Apparently the manufacturer had a problem once with some material that
> may have been an antioxidant. Too liberal use may cause problems but I don't
> know what the specifics of their blanket statement are.
>
> The mixture of WD-40 and graphite is approximately the same recipe as
> other antioxidants - a non-conducting vehicle and small (metal) particles (is
> graphite a conductor?). While I have NEVER seen this approach before and am a
> little suspect of it's effectiveness, if the manufacturer says to do - I won't
> discourage you. OTOH use of a more conventional antioxidant (NoAlOx, Penetrox,
> et.al.) is ALWAYS encouraged and will help the longterm reliability of your
> aluminum joint and do little or nothing to create problems.
it sounds like we're really talking about what is the best
antioxidant/conductor goo to use. i put up a hygain 20m monobander
almost 30 years ago, using, if i recall the name correctly, NOALOX.
it worked faithfully for all that time until the coax shield broke
from flexing a zillion times with the wind. when i took the antenna
down and refurbished it, the joints (after i drilled out the
dimples under the little pointy squeeze clamps) were easy to
pull apart. when i wiped off the thin (somewhat dry) noalox, the
aluminum tubing was still clean and pretty shiny.
i'm not recommending one antioxidant/assembly lube/conductive goo
over another... but i sure wouldn't put up an aluminum antenna
without using one! (butternut's "butter it's not" is a different
color, but it's obviously meant to accomplish the same thing.)
establish, and preserve the electrical connection between your
aluminum tubes!
(i *just* got a force-12 c4sxl up yesterday!)
73,
George T. Daughters, K6GT
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