W4ZW@home.com wrote:
I live directly on the ocean here and I'm here to say that stainless steel
WILL rust. The rate it will rust depends on the quality of the stainless
steel. Some stainless shows surface rust within six months, other takes
almost two years, but it all will rust eventually. Had seven years on the
ocean on the other coast where it rusts even faster because of the easterly
trades.
<snip>
JSheinb785@aol.com wrote:
> Stainless steel grade 316 won't rust because it has little or no iron (Fe) in
> it.
> 73, Joe, WD5FHG Corpus Christi Tx on the Gulf Coast, where Everything
> corrodes!
>
UGGH!!!To repeat my comments from my last post ALL stainless alloys contain
iron.
All of them will "rust" or show signs of iron corrosion discoloration if not
properly treated with chemicals to remove the iron from the component surface.
As stated before, the 316 alloy is one of the best, to resist corrosion. It
still
needs to be properly treated. I have put many 316 parts on the ocean and found
them to exhibit rust discoloration after prolonged periods. I have also put
other. inferior alloys on the same oceans and found them to exhibit similar
corrosion.
Again, UNTREATED MATERIALS ARE WORSE THAN THE PROPERLY TREATED ONES.....
Since, my previous posts on the subject are apparently too long, or too detailed
for most subscribers to read and understand, I will refrain from further
discussions on this subject.
The point in my last post was that one needs to be sure to obtain "passivated"
SS
parts.
Just like with things like antenna gain, and area figures, if one doesn't demand
the details of the source of the information, and description of where they come
from, one is left to his own optimism, to assume he is getting the best product.
316 SS is better than 303 or 304 SS because it has less iron. This doesn't mean
it won't turn brown. Passivated 316 is better than bare 316. 316L is even better
than regular 316.
The statement that 316 "Will not rust" is not true. I've seen it corrode! It
just
does it later or slower than the other alloys.
One fellow has put 316 up at his qth and hasn't seen any (?) signs of corrosion.
He, and we don't know if it was 316 or 316L or if the parts were chemically
treated. So, none of us really know anything, except that if we ask him where he
got his parts, we can go there and get them, but we don't even know that. So, we
can ask the right questions figure it out.
I'll repeat this one more time, all readily available, common "stainless steel"
alloys contain iron. All of them will discolor in corrosive environments. The
most significant factor on how soon they will show signs of corrosion is the
chemical treatment, of lack of it, that is applied to the fabricated parts.
Those
parts that are properly treated are better than those that are not. If you don't
ask and demand the information, you won't know what you are getting. The local
dude at the hardware store won't know what you are talking about, so don't ask
him. You've got to get to the manufacturer of the part!
This is just like the fellow who fixed his Create rotor clamp problems by
putting
a soft aluminum mast in it, that deforms into an oval, when clamped, and lets
the
teeth of the rotor clamp bite into the soft aluminum to make it hold. This is
certainly one solution to the problem! But, we can't evaluate it, because we
only
know that the mast described is weaker than its steel counterpart. We don't know
what the antenna areas, maximum wind speeds experienced, and mast bending
moments
are.
So, we can only say good for him, and do the same and hope to get just as lucky
as he was!
"I'd rather be lucky than good" is a very popular phrase.
Here's to good luck!
73, Kurt
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