Quick RPM Question

[sdemore]

I tried to get the diver out, but he was very unresponsive and finally said he couldn't get to it for a few weeks. I also saw a note about not cleaning ablative paint while in the water of the bay, so I gave up on him. Boat is being hauled and pressure washed tomorrow morning @$8.50/ft ($255). I hope this takes care of the problem.

[sastanley]

Steve, given what we have talked about in this thread, it seems reasonable. Still lots of money, but reasonable for the going rate.

[sdemore]

Wow, what a difference. I couldn't even get the boat to move in a straight line t get out of the slip, let alone back up. Hauled it, scraped a boatload (pun intended) of crap off the bottom, pressure washed it, and put it back in. Runs and moves like normal now. The big surprise to me was, I spent weeks last year sanding down to bare fiberglass, barrier coating, and applying multiple coats of black ablative paint. I couldn't see any black paint today. I expected it to last longer than that.

[sdemore]

Oh, and the other thing that shocked me, there was virtually no damage to the zinc after a year in the water. I expected there to be nothing remaining of it, but you could still read the writing on it.

[Tim]

That's way too many barnacles for one year. I wouldn't use that same bottom paint again. You probably should have re painted while you were out as you will probably have the same problem in a couple of months.

[sdemore]

I'll pull it out in the spring to retreat it, but I'm seriously contemplating CopperCoat. It is much more expensive, but theoretically, I would never have this problem again or have to repaint again.

[Administrator]

Steve:

Did you use Petit Hydrocoat?

Bill

[sdemore]

No, I used TotalBoat Underdog from Jamestown Distributors. It was supposed to be high end stuff, but...

I am awaiting word from them on what may have gone wrong with it, or whether it is just junk. We figured out today, the boat has been in the water two weeks short of a year.

[edwardc]

Wow, what a difference. I couldn't even get the boat to move in a straight line t get out of the slip, let alone back up. Hauled it, scraped a boatload (pun intended) of crap off the bottom, pressure washed it, and put it back in. Runs and moves like normal now. The big surprise to me was, I spent weeks last year sanding down to bare fiberglass, barrier coating, and applying multiple coats of black ablative paint. I couldn't see any black paint today. I expected it to last longer than that.

It HAS been a bad year for growth, but that's excessive. I used to use CPP Plus with good results until they started reducing the copper content (but not the price!)

Lately, I've been using Mar-Pro Super-B-Ablative. It's a copolymer paint. I put on two coats, and I usually get two years out of it, with a short haul and pressure wash in the off year.

Here's a photo of what it looked like this past spring after two years. Lot of slime, but not any hard growth on the hull.

Oh, and the other thing that shocked me, there was virtually no damage to the zinc after a year in the water. I expected there to be nothing remaining of it, but you could still read the writing on it.

This means either one of two things: Either your prop and shaft are stainless, so there's nothing much to protect, or your zinc is not in good electrical contact with the shaft. My zincs have a little spring-loaded copper ball on the inside to inure they remain in good electrical contact with the shaft after the corrosion has started. The shaft should be unpainted under the zincs and wire brushed shiny brite before installing them.

[sdemore]

I sanded the area of the prop shaft where the zinc is, then taped it off before painting the shaft with the ablative paint. The zincs have the spring loaded balls in each side and I was told to smack both sides with a hammer to ensure good contact. The prop isn't stainless (brass or bronze colored), but I don't know what the shaft is made of. I didn't wire brush, but did sand it clean. I've heard that without power on the boat, the wear is less, but I don't know how true that is.