Living in Florida means you have to accept that things rust, and rust
fast.... with plated items you can see rust appear in a week - HONEST!
As such I use ONLY stainless steel bolts, and u-bolts on all my yagis...
they cost most, they don't torque down as well and they tend to gall if
you are not careful and there is the fact that against aluminum you have
that galvanic battery action going on - BUT - they are also usable as
hardware for years and years here.
I highly recommend using ss hardware on antennas, it is the only way to
go... it does take practice learning not to tighten things like you are
in a masters of the universe throbbing veins mode but with that caution
you end up with antennas that can be easily reworked for years and years...
I currently have ten antennas in the air for 10 through 40 and hope to
add more this Summer... all will be totally assembled with stainless
steel nuts, bolts and u-bolts.
73,
Jim, K4OJ
near Tampa, FL
Barry L. Ornitz wrote:
> George Skoublis, KF9YR, asked:
>
>
>> Is there any galvanic action to worry about when using
>>galvanized u-bolts with an aluminum boom?
>
>
> The zinc coating on the steel, which makes it galvanized, is
> more compatible with aluminum than any of the various
> stainless steels from an electrolytic standpoint.
>
> There is about a 0.4 to 0.5 volt difference between common
> stainless steels and typical aluminum alloys. Compare this to
> about 0.1 to 0.15 volt difference between zinc and these same
> aluminum alloys. From a corrosion standpoint, you want this
> potential difference to be as low as possible.
>
> The only problem is that plated zinc hardware has such a thin
> coating of zinc that the zinc is quickly depleted. Hot-dipped
> galvanized hardware is to be much preferred.
>
> 73, Dr. Barry L. Ornitz WA4VZQ ornitz@tricon.net
>
> _______________________________________________
>
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> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
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>
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