prop and shaft anti-fouling

[Strygaldwir]

I know the anti fouling isn't working. Hard to imagine the STP working. But for $5 and a short trip under the boat, it's worth a try!

[Pun Pun]

I just read in the recent Boat Works that you should not paint a bronze prop, the prop and copper based paint react and you know what that does. they also mention not to paint the anodes

[hellosailor]

"Are you saying that using STP. Like the same STP that you use in cars?"
Same STP, and I don't use it in my car either. My car does OK without magic elixirs.

Strygaldwir-
Remember, that's $5 for the STP, plus $10,000 for the EPA fine for discharging oil in the water.<G> Anything that leaves a visible slick, and I'm pretty sure STP "oil additive" will.

PunPun-
Painting the anodes would cover and insulate the anodes. At which point they are no longer anodes and no longer protect anything. Parlez-vous "oopsie" ? <G> One of the few words the FCC will allow you to say over the radio, which should strike fear in the hearts of bold sailors.

I can't help wonder...if you bought a big bottle of the 3" pool chlorine tablets for $15, and stuck two tablets in a closed plastic jug with a pinhole in it, so they could dissolve out slowly around the boat....might that chlorinate the water around the boat enough to kill off the critters? (Without dissolving the plastic boat?<G>)

[Strygaldwir]

Yeah right! You should see the stuff floating in the water where my boat is!!! It is the most disgusting set of crud I have ever seen. The EPA should be down here writing fines for that .... stuff. Seriously, there are dead fish and some nasty looking foam, beer bottles, dead crabs, old logs, rubber gloves, and that's just today. Last year I tried pulling stuff out with a net, this year I am only removing the dead fish and logs. Not worried at all about residue that may, or may not come off my prop. I put on a full wet suit to go in the water, and I only do so when I ABSOLUTELY have to. We are at the intersection of the Neuse and Trent rivers in New Bern North Carolina. Perfect place, except for the water and sometimes the heat!

Not a chance on the tablets. I used them on my pool for years. They are great there because they slowly leech off into water that is not changing. If you put one of those plastic damns under your boat, they would work well, but you probably wouldn't have issues with barnacles then, only algae.

Anyway, yes, one should take great care in painting the props. My current props are aluminum and the copper in most bottom paints will cause them to pretty much disintegrate. The Trilux is supposed to be good for that. You folks with bronze props have it a lot simpler.

[fred]

Strygaldwir...tuff letters to find...

We're sitting in the Cape Fear River waiting for parts...
You are right on the money. The stuff floating by me is amazing....
the EPA should be out here with bags...body bags....!!!!

A little STP would clean up the "Tea Water" goin' by.

When we got in from the little offshore jaunt, I was going to jump in for a swim and clean up the intakes and mechanicals...duh....
They are probably cleaner than the water.

fred

[Gallivanters]

I've just painted our new prop.

While hauled out a few years ago in Langkawi - I noticed a crowd beginning to gather around the stern of another boat which had just come out. The owner had installed a new propeller more than a year earlier - and the price & pitch could still be read on the prop!

There was uniform growth all over the prop except where it had been written on with some sort of magic marker.

I saw it with my own eyes and I was impressed.

Navy Doctrine always said it's "better to try anything than to do nothing"... so I've just "painted" my prop with a half dozen Sharpie Pens and I will report the results in this forrum when we haul out again next year.

Carry on,

Kirk

[Strygaldwir]

I wouldn't put STP or any oil addative in my car either. But I am pretty much a firm believer in synthetic motor oils. Use them in pretty much everything, except my sail drives.

Cheers,

Keith

[fred]

Kirk,

You may be on to a great money maker...
We're livin' and working on boats....HOWEVER ....
if you find a way to prevent growth on the bottom of boats.....

I'll shoot U....no barnicles, no grass....no slime....

Anne, get my gun !!!!!

Just kiddin'...No growth !! please keep us updated......

fred

[Alan Wheeler]

Just to cover a few comments made above.
Correct, NEVER EVER paint copper based paints on Aluminium props or ali anything for that matter. Take a look at a prop I posted in the gallery sometime back to see why.
You need a hard coating to handle a prop and most copper based are not hard enough. A hard high speed antifoul designed for ali hulls works best on Bronze and ali props. You must keep any copper based antifoul at least 3ft away from any Aluminium. So sternlegs and props that are Ali, must have a clear 3ft distance to any copper based paint.
Use the same hard antifouls on high water speed areas on even displacment boats. Such as leading edges of rudders etc. Soft paints wear away too fast from the prop wash streaming past.
Kirk, I too have seen the very same thing. I don't know why. It was just the writing that remained clearly visible. Real strange, but I never thought about trying to coat the entire prop. I have wondered about a teflon paint though. Not antifoul, just teflon paint.
Kieth, your water is WHAT!?!?! eeeeewww!!!! I would want to be well covered in a suit before I would go plunging into that mess. I am not sure I would want to go dregdging up to much fromt he depths, you don't know what may come to the surface. Do you have the mafia in your town??? ;-) hmmmmm concrete boots with something attached come to mind.;-)

And finaly, I recomend synthetic oils in saildrives. The reasons why the regular services are recomend is for possible seal failures and the resulting water ingrese. So regular oil changing ensures you keep a watch on water contamination. Gear oils do not break down so easily as a motor oil does. However, a gear oil is destroyed very quickly once water enters and mixes. It does not take a lot of water to break down gear oils EP strength. Synthetics have the major advantage of being hydrophobic and do not mix with water when agitated. It maintains a high EP strength and will still perform well when water is in the gearbox. So added protection is being offered to your gears till such time as your regular inspections detect the presence of water and you rectify the situation.

[hellosailor]

Keith-
" We are at the intersection of the Neuse and Trent " isn't one of those the river where they found some nasty critter in the water because of all the pig farm effluent or something....that just contacting the mist can cause a reaction that kills you? Serious X-Files stuff where a researcher nearly died from inhaling mist from a tank full of the stuff maybe 2-3 years ago, no kidding. I remember saying to myself THAT'S not the kind of water I want to be around.

But the EPA doesn't do much unless someone starts up a bandwagon. Calls some of the pollution numbers, gets the media in, and doesn't have too many pig and poultry farmers to outbid at the lobbyists table.

[swagman]

Hi All,
Think I've suggested this before but was taught this long ago in Oz - and it works.
Simply clean then polish the prop so it looks like new (I mean polish - not just scour the surface) and then rub all over with an Permanent Marker Pen.
I've done this now for over 20 years and it seems to keep my props clean of growth - in woarm as well as cold climates - for at least a year.
JOHN

[Alan Wheeler]

John this marker pen sounds interesting. So does the pen stay on after a year?? do you think it is the highly polished surface or the Pen or the combination??

[swagman]

After a year the surface finish looks flat and dirty but it's usually clean. We choose to re-do it each year as I don't want to waste a second slip in case it runs out - but can verify it works well for the 12 months.

JOHN

[SkiprJohn]

Sorry to ask really dumb questions but I have no boat yard within 100 miles to go look around and its been a long time since there has been an anode on my boat.
The questions are: Where do I put the round shaped anodes on my prop shaft?
I have 4 feet of stainless prop shaft then a bronze strut with a cutless bearing, then a little more shaft and the bronze prop.
I'm thinking they should be very close to the prop, either just ahead of the cutless bearing or just ahead of the prop hub between it and the cutless bearing.
Do I need a zinc on the bronze strut?

Thanks folks.

Kind Regards,

JohnL

[Alan Wheeler]

OK, firstly a good question is, what is the boat made from??
As for the saft, there is two ways of doing this. You can have a large Zinc or series of them on the hull and the saft bonded by a "shaft brush" internally. This is a common approach wehn the hull has many metal materials penatrating at variuose points all over. i.e. bronze through hulls, rudder shafts etc etc.
For a hull that the only metal in the water is the shaft and prop, a single round anode will suffice. It can be placed anywhere ont he shaft, but close to the bearing is best as the shaft has the greatest support there and vibration will remain a minimum. Before or after is determined by room to fit the anode.
Now for the strut. Any metals under the water line MUST be protected. So all metals MUST be bonded together to ensure they are all at the same potential and a common anode must be fitted somewhere. Where will be determined by keeping all connecting cables are short as possible. If the strut is the only other metal in the water, then a single anode mounted to that is fine. In addition to the shaft anode that is.

And to finish, it is important to get the right size of Anode. Usually a good rule of thumb is an anode that will bet mostly eatin away in approx 12months. So if your boat has been without an anode for longer than 13mths, you had better get it out of the water real quick, or you may not have a prop left. Inspect the prop for pinkish bloches all over it. This is a tell tale sign of de-zincification and if that is really bad, it can mean a new propellor.