Velox Plus Sterngear Antifouling Report

[Deleted User YDKXO]

Some of you will know that the Med boats are subject to very aggressive fouling of exposed sterngear and bowthruster parts. Its common for boats to lose several knots of speed in only a few weeks during Spring and Summer. I have tried PropSpeed in the past with no success and I had resigned myself to using the services of a diver 3-4 times per season to keep my sterngear clean. This year, I tried a new treatment http://www.marlinpaint.com/EN_MARLINPAINT_HOME.html which another forumite, Hurricane, found. This was applied to the sterngear on my boat at the end of April this year. Unlike Hurricane who took his boat on an extended cruise after applying the Velox Plus treatment and found that the treatment did not properly adhere to his sterngear, my boat sat in the marina for most of the period since the treatment was applied with only a few short trips out. In my case, the paint did adhere quite well to most surfaces in the 2 1/2 months since it was applied but the boat was still 3-4 knots down on speed last week. On inspection, it appeared that barnacles had attached themselves to even paint covered parts so it appears that, in my case, adherence of the paint wasn't a problem but the antifouling properties of the paint itself were. The fouling was probably not as bad as it would have been had Velox Plus not been applied at all so I have to say that it was partially successful but, disappointingly, not the solution that I was hoping for

 

[Hurricane]

Thanks Mike

I was only able to test for adherance (if there is such a word) - it didnt stay on long enough to see if it worked as an A/F.
Others here in Sant Carles are still trying the Velox - some with confidence that it will work for them.
I'll keep you posted.

For me I can report yet another failure.
When we got back from Malta, I used the Blakes "two part" primer which I believe is an epoxy based treatment. After treatment with this two part primer, I then painted the sterngear with normal hard racing A/F.

The bad news is that the A/F isnt sticking to the primer but the good news is that the primer seems to be sticking to the props. I havent confirmed this yet -need to do a few more passages to be sure, but if this IS the case, then I have a proposal that might be worth a try.

The Velox primer is an "etching" primer - in that it "keys" itself to the props chemically. The "two part" primer that I'm using at the moment, being epoxy based "sticks" itself on with brute force - my opinion of course.

Recapping then - we have two problems - making it stick and then making it work as an antifoul.

Now, if the two part stuff actually sticks to the props, we only have to make sure that the primer has antifouling properties.

So - a TCM solution

Mix the primer with copper granuals and apply as a single treatment - two coats should be enough. It has to be applied quickly because it starts off like applying treacle - soon becomes like porridge and then turns to a putty consistancy. Mixing small quantities seems to be the way to do it - all that will be need is a few spoons of copper in each mix.

All this, of course, is a complete waste of time if I find that the two part primer didnt actually work after all.

It would be interesting to hear others opinions.

Mike

 

[Nick_H]

Thx Mike

I was also planning to just scrape the props a few times, but at the last minute decided to spray them just to slow the growth until the first big trip, when I fully expected it to all fall off. I didn't polish, or even sand, the props first, they were just powerwashed and acid cleaned, then a few crunchy bits scraped off before I sprayed them.

The chandler on site only had a few tins of prop spray, so I had to put Blakes Mille Drive with Blakes primer on the stbd props, and Trilux prop o drev with Trilux primer on the port props, and on the plastic bowthruster props.

After 2 months, and a 400 mile trip round Corsica, the Blakes had almost entirely gone, but large areas of the Trilux were holding up well. I reckon the bits that are not covered now, are the bits that weren't clean when I applied it. If that's right, then if I had sanded the props first, the Trilux may have kept a good coating, and there was no sign of any barnacles. The boat is on charter now till mid Augfust, but i'll see how its doing when we next go to France.

The Trilux on the plastic bowthruster props is still completely intact, and no signs of any growth.

 

[John100156]

Mmmmm interesting. I do like where your going with this Mike. I hope the copper granuals do not impede the stickability? Worth a try though!

The Velox as expected didn't last very long on my props, about two months, and we only went out local in the lagoon a handful of times and one 56NM round trip. I am now resorting to scrub and polish on the props every two weeks, it's easy with the T34 sterndrives, you can pull the drives up and scrub the props from the bathing platform. Forward props do need long arms though!

We should immerse a sheet of metal at the end of the pontoon with your magic formula applied one side, and an alternative on the flip side. Might be interesting to compare the results after a couple of months!

 

[wakeup]

Copper plating

Has anyone ever thought of copper plating their stern gear, rather than going to the effort of painting it all the time with disappointing results. I am guessing you could take props off and have them copper plated, rudders and props might be more problematic. Is it possible to electroplate a piece of kit in situ?

 

[Laurie]

For what it's worth, have just applied Velox to my brand new 2 bladed Autoprop.......we'll see?
The boat is moored in the Blackwater, on the east coast, in a creek, floating. High salt but high fouling.........