Effective Anti-Fouling for Props

[Ti' Punch]

Does anybody have a recommendation for effective anti-fouling for props? I've got a pair of Gori folding props on my cat and in less than a year they have become so fouled that I can't make rated RPM on the engines without producing black smoke. We started to go out today for the first time since mid July, but immediately noticed the reduced speed and smoke from the engines. Back to the dock where I jumped in and checked both props. They were both heavily encrusted. These props were brand new 10 months ago. When I put them on, the yard manager suggested I use some paint that he had left over from another job to keep them clean. The paint seems to have been totally ineffective. By comparison, Micron 66 has kept the hulls, mini-keels, and rudders pretty much clean during the same time period. Does anybody have first hand experience with prop anti-fouling that works? Thanks.

Chris

[Ex-Calif]

Oh if it were so for me. Our prop fouls in less than 4 months and I have to dive on it.

Paints will ablate off the props very quickly. There are a couple of thread around her recommending some stuff out of Australia (maybe someone will chime in) but I haven't tried it.

So far in 5 years I haven't found the magic stuff..

[svBeBe]

We had Prop Speed applied in New Zealand. For one year it worked beautifully. But almost as if a timer had been installed, at exactly one calendar year the effectiveness stopped.

Nothing else we have tried worked nearly so well. Coating with lithium grease did nothing. No paints we have tried stay on the prop more than a few weeks. Having the Prop Speed last for a full year was a very welcome surprise. Our next haul-out will be in Turkey. If it is reasonably priced there then we will apply it again.

Judy
S/V BeBe
Amel SM2 #387

[senormechanico]

Sharpie pens were recommended as well.
I tried it and it was the biggest failure yet!
Myth Busted!

I even posted a pic here somewhere.

[matauwhi]

G'day, Mates. A second for prop speed. I've been using it for 10 years now. I get about 18 months effective use. The key, as with any coating application, is to do a good preparation job. I also coat our bow thruster blades. Cheers.

[Ex-Calif]

Originally Posted by senormechanico

Sharpie pens were recommended as well.
I tried it and it was the biggest failure yet!
Myth Busted!

I even posted a pic here somewhere.

Yup - Me too.

The yard applied Micron extra once and it lasted a couple of weeks and was a mess to get the remainder off.

We clear lacquered the prop and that worked well but only lasted couple of months.

Prop Speed is the stuff I want to try. Can't seem to get a small quantity here and I certainly don't need a gallon of the very precious stuff...

[S/V Illusion]

Petit makes a zinc coat prop spray which, if used as directed, is very effective and surprisingly cheap. One can can last for years with an annual recoat required to maintain efficacy. It is not 100% effective, nor is anything else, but I have found it to be remarkably good.

[Ti' Punch]

Thanks for the responses everyone. Looks like WestMarine wants $400 for 1000 mL of Prop Speed. I guess that means there is some diving and scraping in my future. At least I'll be in good company.

[Ti' Punch]

Ah, just as I had thrown in the towel, S/V Illusion comes through. Pettit Zinc Coat Barnacle Barrier is going for about $19 a can from iboats.com. I will give it a try. Thanks again.

Chris

[James S]

Is there any reason not to take them off and have them copper plated?
I've had lots of chrome plating done here over bronze, and the first or second layer they do is copper before the final chrome.

[Tropic Cat]

I too am barnacle challenged and have my props scraped every 4 or 5 months. Copper plating sounds like a very cool idea... Has anyone tried it?

Does anyone have any idea how thick the copper plating would have to be to last long enough to be cost effective?

[Pete7]

Had reasonable success with a thin coat of Internationals Primocon over a well prepared bronze prop ( as in angle grinder and wire brush attachment). This was followed an hour later by a thin coat of abalative antifoul paint. Couldn't wait any longer as the tide was coming in. The angle grinder with a steel cup wire brush looks horrendous and likely to rip a bronze prop apart. Actually what happens is it gives a really good smooth finish taking all old paint, weed and barnacles off in 30 seconds, excellent bit of kit.

This year tried a special paints undercoat. Its rubbish and falling off so not doing that again.

Also bought a can of motorcycle chain lube. Rumour has it works very well. Not convinced, but might give it a try next spring.

Pete

[Wotname]

Originally Posted by James S

Is there any reason not to take them off and have them copper plated?
I've had lots of chrome plating done here over bronze, and the first or second layer they do is copper before the final chrome.

Originally Posted by Tropic Cat

I too am barnacle challenged and have my props scraped every 4 or 5 months. Copper plating sounds like a very cool idea... Has anyone tried it?

Does anyone have any idea how thick the copper plating would have to be to last long enough to be cost effective?

Please wait another couple of months!!!!

I had my prop copper plated and it was launched December 2009. So far have done 25 hours motoring and no real barnacle growth to date. It does slime / weed up but this spins off once the engine is run.

But really it is too early to tell - I will report further towards the end of the year .

[wallandj]

Getaprop.com has a nice menu of prop coatings:

prop speed, propeller coatings, prop coating, propspeed

I have not used the Hawkspeed or Petit stuff but I have successfully used Propspeed. We haul every winter and it lasts nicely for 1 season in the warm waters of the Chesapeake. However, it is a lot of work to apply. The metal must be clean and greasefree and the multi-coat application regime is complicated. (I think a brief incantation is also required.) The top coat appears to be a soft silicone-based material that would probably not hold up to aggressive scraping or brushing. Its expensive, too, but it allows me to skip a midseason powerwash and I have no performance degradation in late summer.

[bstreep]

Four months? I have to scrape our prop every 2 weeks during the "growing season" here.