props

Actually the issue of balance rings a bell. Bottom paint is heavy, but then again, growth on the prop would be heavier, and less uniform.
Capt Lar, don't trust the ones with pretty eyes. They are usually wolves in sheeps clothing

[CaptainK]

Baaa Baaa Baaa Baaa

Now wear did I put those velcro gloves at? :-)



Regards,

Kevin
CaptainK

This is getting really baaaaaaad

[CaptainK]

Bad Boys Bad Boys. Whatcha gonna do, when they come for you?

[Alan Wheeler]

DO NOT use Copper based paints on Bronze props. Copper and and Brass, two dissimilar metals. It's different to Copper in Brass making Bronze.
As for lanolin, it doesn't stay on for long, (depending on what you may call long). Just depends on how long is long enough for the individual. For me, I haul every two years, but that is becuase we get little growth in our Marina, due to large fresh water flushes coming through from rain. For others, it maybe as little as six months, as their seasons maybe short and they haul for their winters.

[Sonosailor]

Canadians have to haul every fall. Snowbird Canadians typically haul every summer, fly home for a bit, then fly back to the boat for the winter. So, for many of my crowd, 6-8 months of protection with the lanolin would be just fine.

I wonder if the stuff can be applied under water. The "**** to a wool blanket" comment made here earlier suggests it could.

We'll see, for both issues.

[Sonosailor]

I believe, Alan, that the problem is especially pronounced for copper-based paints on aluminum - say for the saildrives. In some jurisdictions, the aluminum engine parts are the only legal location where pleasurecraft can apply the tin-based paints.

As the copper is a more noble metal than aluminum, it creates a current with the aluminum in an electrolyte (salt water), allowing the aluminum ions to leave the parent material (i.e. rust). (as I understand)

Actually, the nobility of metals is a great issue, and we should deal with it as a separate thread here somewhere. I'll look around for info.

[GordMay]

For Galvanic Series, goto:
http://www.cruisersforum.com/showthr...&threadid=2469

[Sonosailor]

Guys, the lanolin didn't work. I am sitting in Antigua, and have been scratching away at my props under water every 2 weeks or so since launching in Trinidad, 3 months ago. I just smeared it on, and attempted to maintain the coating under water. The smeared, on-the-hard installation didn't stay, and it just doesn't stick under water. A friend attempted to burn it on with a torch - as advised by another Kiwi, and it was no better. I have scraped his props for him in Bequia. Let's keep working on this.

[Alan Wheeler]

Sorry to hear, but you are correct in your findings, the stuff doesn't stay on for long.
The only way you can keep the prop clean long term is to apply a hard anti-foul. A good one that we use to use here, used to be called Boot topping. But I don't think you can get it anymore. It didn't have copper in it, so above the waterline, it stayed the right colour. Greeny blue copper oxide didn't leech out of it.
What I suggest is to look for a hard anti-foul. And one for aluminium hulls would be best. Because the prop is spinning so hard and fast, it doesn't need to be as clean as the hull. Any growth that does adhere, will wipe of in short time from the speed of the prop.
It may not hurt to mix in to a anti-foul, a good amount of Cayen pepper. I have no clue as to it working. It is just a story I heard from an "old sailors tale".
I do however have a deploma in paint technologies. No it doesn't make me an expert in paint. But I do understand a little about the chemistry of the stuff. I even developed my own special coating once for "silver screen" home theatre projection walls. It was a highly reflective paint that did not reflect glear from the projector. I had the most amasing home theate screen on my wall. Sadly, no companies were interested in it. It seems they..... Oh thats another story.
Anyways, I have often thought about making a paint with a highly slippery surface. I know some have tried Teflon, but I don't think that works either. Hmmmm, might be time to go play in my shed.

[capt lar]

Sonosailor - Sorry to hear you are stuck in Antigua with a slimey prop. I guess we all have our burdens.
I am available to come down and consult with you. Alice (my sheep) would enjoy a vacation.

We will continue our research in the frozen north. Fair winds.

Larry

[delmarrey]

If your just sitting around the harbor, why not just cover the prop(s) with a plastic bag with a rubberband holding it in place. Sea creatures need food and sea growth needs fresh water. If you need to get underway in a hurry the prop will just shread the bag.

With a bag over the prop stuff can't grow, except maybe bacteria. It sounds like you've been getting wet anyway, so give it a try??? Clean the prop first, of course..........................._/)

[CaptainK]

Hmmmmm...............?

Hey delmarrey.

Now that's what I call simple & effective?

Funny how the simple things, can make a job more easier?



Oh Kai Nui. Check you're email?

[Lodesman]

Not surprised the lanolin didn't work. Maybe you should try a high-pressure silicone grease. Don't know if it will work, but the stuff is tenacious. You can get it at auto supply shops.
Or thinking outside the box, how about plating the props with copper - either electroplate or flame-sprayed. Just an idea - no experience to back it up.

Kevin

[Jentine]

A friend gave me some "stuff" he had acquired in Venezuela several years ago. It was a two part application. The first coat was white and the second was green. Never since has there been growth on my prop. I have no clue as to the contents as I don't read Spanish.