Does ablative paint lose potency?

[Tom1340]

My boat is in the water 6 months/yr. For the eight years I’ve owned her, my routine has been the same. It was suggested by the previous owner. I Power wash at haul out, then before launch, power wash again and put on one coat of west marine cpp ablative. It has served me well. But I have built up the equivalent of about 4 or 5 layers of paint. So do I need to repaint? Can I run for a couple of seasons without new paint, and rely on the old built-up layers?

[rslifkin]

Typically, if an ablative is still on the boat, it's still working and you can just wait to paint until it wears down more. The only exception may be if the boat spends a ton of time sitting and doesn't move much. Then it may leach out and become dead like a worn out hard paint (although it will still continue to wear off).

[valhalla360]

I would keep the power washing to a minimum...just a quick hit at haul out. Otherwise, you are blasting expensive paint off the boat and into the drain.

As long as the paint isn't worn thru, ablative paint is working.

One trick is to pick a different color for the first coat. Then if you ever see that color, you know you need paint. We often will just do a touch up prior to launch. Often just the leading edges of the bow and rudders have the paint worn down.

[Shrew]

You'll need to read the manufacturers warnings. Many ablative bottom paints can't simply be re-launched after being hauled out for a season. Some can. Some will need to be 're-activated' by lightly sanding the bottom just prior to launch. Others need a light coat of paint.

Like hard paints, after 10-15 years, even with an ablative, you might need to have the bottom scraped or media blasted, barrier coated and repainted to reduce weight.

[Tom1340]

Thank you r, v, and s. Your comments are much appreciated.

[Ardbeg]

Tom: I have the same routine as you being on the Great Lakes. Since the boat was new, I have used Pettit VIVID paint, color white. So my undercoat is a different color than the Pettit. It shows thru when the Pettit wears off. IN 10 years I have only done one complete coating when I was headed to the Gulf of St Lawrence. Each fall I pressure wash, lightly to get it back to white. In the spring I look for grey color showing thru. Obviously it happens more on high wear areas like keel and rudder. This past summer I changed docks due to potential for low water. The dock last summer had a rock bottom and in the fall the boat was still fairly clean. Other years I was over a muddy bottom and the mud clung to the boat after a full summer. I also had less sun access to the bottom of the boat this past summer so I believe that also inhibited algae growth on the bottom. So for 2022 I will be back to muddy bottom as I believe the water will rise a lot for next season. With this plan I go thru about a quart of paint a year on a large boat.

[sailcrazy]

Following. We have been using Micron 66, and were told by a yard in the Medd. that it needed to be "lightly sanded" and then recoated every year. We followed their advice, and have been reapplying new paint every year for the past 9 years. Because Covid kept us from traveling last season(Nov-May), the boat has been on the hard for nearly 18 months. Although the hull was smooth when we hauled out, this summer the yard here alerted us that we needed to strip the hull due to the significant cracks and craters that had formed in our hull paint??? After getting several pics, and several discussions with the Micron 66 tech reps, they determined we had "corn rows" in our paint, that heavy sanding in those areas and light-med sanding on the rest of the hull would resolve the issue....and then recoat with Micron 99. We've now done that, and are due to resplash in a few days now. We'll see how it goes thru the season, but I wish I'd seen these comments some years ago. Obviously the rwal fix is to strip and start from a clean bottom....but the prices quoted here in Puerto Rico to strip the bottom are "off the charts" high-north of $10k! I'm looking for more info on media blasting, who may do that, and what the fees may be-if anyone might know.