But I'm 40% zinc!!
The Ministry of Defence's naval arm maintains a regular publication focused entirely on types and shades of paint. It is not a spoof – or if it is, someone's gone to some serious lengths on a windup. The magazine, snappily titled Warpaint, is an attractive coffee-break reading proposition, comprising 80 pages of black-and- …
Is it a galvanised coating, zinc dipped, zinc alloy? Anything you look at or think about has hidden complexity that demands more questions and deeper understanding.
If the dedicated band of painting people didn't have publications like this to learn from and promulagate their craft then the world would slowly fall apart. This publication should be celebrated, not derided. (I'm a keen amateur painter and am experimenting with the use of Hammerite satin finish paint on shed hinges for long term weather protection.)
"Is it a galvanised coating, zinc dipped, zinc alloy?"
The propellers are made of a copper alloy which contains zinc. Some electrochemical processes can lead to the zinc being preferentially removed, resulting in porosity. Effective earthing/equipotential bonding can prevent this. (A similar problem can affect brass plumbing fittings in areas with particularly soft water. Hence these fittings are now made from dezincification-resistant (DZR) brass.)
"Anything you look at or think about has hidden complexity that demands more questions and deeper understanding."
I second, third and fourth that. [old git mode on] But unfortunately we live in an era where folk are apparently tired of experts and think we can look everything up in Wikipedia. [old git mode off]
"If the dedicated band of painting people didn't have publications like this to learn from and promulgate their craft then the world would slowly fall apart."
Though, speaking as an equally keen painter, I'm not that impressed with Hammerite.
so that explains Borraloola waters destruction of brass taps. Another place south of Katherine had nice tasting water that eroded Al pots overnight. Fresh holes in base in the morning after the night before non-washup. So these odd publications can be useful. But I digress.
I once had to do a small tender for refurbishment and painting of Naval buoys. Paint specs document was about an inch thick IIRCC. All work was done beautifully, fully inspected and up to spec, right up until the buoys were delivered to Stores and dropped off truck onto hard ground, breaking paint, all 6+ layers.
if you're looking for serious long term protection of any material outside, including steel, wood, concrete, dog and cats I can happily recommend Bedec Barn Paint. It is truly wondrous product with superb stickability and wear resistance. It is unbelievably good. Used by canny farmers and discerning tightwads throughout the UK and Colonies.
I have no fiscal interest in this product etc, etc ...
Can I ask the paint guru's, what's your thoughts on painting Hammerite over rust?
The spare wheel on my Peugoet is suspended under the boot, so it gets covered in water, road salt etc, and is consequently getting a tad rusty. Is it ok to scrape off the worst of the rust and give it a quick coat of Hammerite?
I hope so because I've already done it.
>>>> Paris, because she's also keep on uncorroded spares.
It's actually of huge interest to the narrow boating fraternity, most barges being made of steel like battleships are.
NB most narrowboats employ a sacrificial anode made of alloys of magnesium or zinc to offset the loss of iron that occurs as a result of the boat's electrical system. Electroplating etc etc.
The article seems to be mocking the subject matter of a magazine because the author of the article finds it funny that someone might find detailed specialised information relating to something outside their experience necessary, relevant or even interesting. This seems to be an unfortunate angle to take on a website aimed at technical people.
I appreciate that El Reg has become increasingly tabloid of late, I wasn't aware that it was reaching for The Sun.
"The article seems to be mocking the subject matter of a magazine because the author of the article finds it funny that someone might find detailed specialised information relating to something outside their experience necessary, relevant or even interesting. This seems to be an unfortunate angle to take on a website aimed at technical people."
100% agree with this. It seems like this information would be of importance to people who carry out maintenance on warships. It isn't like they are buying it from their local WHSmiths and rushing home with it.
Slow news day, huh?
Due to bad corrosion and many trials of coatings on metals for one item open to sea, fresh water and all in between, the staff 'painted' over corrosion just before inspections. Eventually pain shell no innards. Replaced metal with wood( yes, a hard wood Lignum Vitae); it worked. Worked for many years between replacement versus 2~3 years for coated metals.
It's actually very much a). The right coat of paint is massively important for fuel economy and to prevent excess noise/damage.
The ideal coating would be perfectly smooth to reduce drag and maintain a nice laminar flow into the propulsion system, while resisting marine growth and preventing corrosion. It would also be non-toxic so as not to cause too much environmental harm (we care less about the poor sods in the dry-dock who have to blast it off and spray it on, but it's a thought).
There's all kinds of approaches; the old style is heavy metals to try and discourage marine growth, newer stuff intentionally never quite dries fully so a thin coat can flake off once the barnacles get too thick.
It's narrow-focus technical literature, but very much not a joke or really that boring.
marine coatings are a complicated issue not just for the jolly jack tars. My GRP boat was moulded in light blue. The previous owner applied Awlgrip in navy blue but that is now very tired but I can't afford to pay a professional the £5k odd. Ergo I am looking at how to get a two pack polyurethane to achieve the same effect.
Then there is the copper antifoul below the waterline. Conventional antifoul uses copper compounds in a friable substrate and has to be replace every year or so. Mine is three times as expensive and has metallic copper in an epoxy substrate and should last ten years.
Even the deszincification bit is important as the propeller is made from bronze (contains zinc) while the prop shaft is stainless. This sets up a galvanic cell and will eventually reduce the expensive prop to a spongy mess of copper.
I won't even start on the brightwork!
Geekiness of a very high order and mine is the one with powdered copper in the pocket and epoxy stains on the sleeves.
As I vaguely recall before my boat was stolen, there's:
-sacrificial component...with some metals, dropping it in the sea makes the whole thing act like a battery, so you add a sacrificial bit that erodes instead of your expensive metal bits. I'm sure someone containing less beer will be along in a moment to clarify
-how poisonous you want it to be...you don't want barnacles and suchlike making happy homes on your hull and yet you don't want the square mile around your boat glowing green with radioactivity and decomposing seagulls. It's a balance thing.
Oh yeah, if it's a GRP hull, some paints (well the solvents) can fuck it right up. Even stickers...makes it go brittle and fragile, like those old plastic lawn chairs that snap a leg off and dump you on your back at barbeques.
Having worked at the Univ. of Texas libraries and being in a postition to see ALL the perodicals subscribed to, this one is outre, but dull. My all time favorite one, tho, was "Emegency Librarian". While being a catchy title, I was at a complete loss as to why it was even called that. Sounds like something from Adult Swim, however....
Someone in reg mentioned they liked red dwarf? I wonder if that's what made them think you'd be interested.
(Arnold Judas Rimmer being a fan of both ocean gray and battleship gray....just not at the same time)
On an unrelated note, I'll have to post this on to my cousin once he gets back from sticking offshore wind farms up as they'd have similar issues I'd suspect.
I'm all for a good laugh at someone else's expense, but you're aware that paint in difficult environments is a hobby for some and a living for others?
These folks probably look at people who run websites (that endlessly prattle on about "new" ideas like cloud computing that are clearly just rebadged versions of ancient ideas like mainframes) a pinch askance. At least their silly paint magazine has things like chemistry and modern research, and not just a shiny marketer's interpretation of the 1950's.
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