What type of bottom paint and why?

[rwthomas1]

I am looking at the list of things to do over the winter and one of them is new bottom paint. In the past I have used a single season hard ablative but likely the boat will be in the water for the following winter so I am looking at multi-season paint. IIRC the Interlux Micron is a good multi-season but its a soft ablative. What I would like to know is the difference between a hard and soft ablative? Or maybe a hard epoxy paint would be a better choice? What do you all think?

Lastly, I am considering a barrier coat job at the same time. The boat has no sign of blisters now or when I bought her but I don't want to have any issues. Good idea or bad?

Thanks, RT

 

[NateHanson]

Personally, I think hard paints are the bottom paint of the devil. They build up for decades, and then start to flake off unevenly, leaving a horribly uneven surface. To remove them you need to scrape and sand them off (UGG!) or walnut-husk blast them.

A good ablative paint like Micron will last a couple seasons in northern climes, wears off as it wears out, and can be washed off with a pressure washer or light sanding.

I've blasted the bottoms of two boats to remove decades of hard paint, barrier coated them, and then started with about 5 coats of micron. I use 2 coats of one color (red) followed by 3 coats of shark white (more on high wear areas, like the leading edge of foils). If I start seeing red, I know it's time to paint. But if the white color is holding up well, I don't paint between seasons.

Nate

 

[Kevin Johnston]

Ablative

I have to agree with Nate, I have gotten multiple season by layering Micron Ablative. Next time my Ericson is out of the water she will get another 5 coats as well.
KJ

 

[Captron]

Ameron

I used Ameron ABC #3 ablative paint on Kismet 2 years ago here in Florida. I put 3 coats on and it is pretty thin now. We'll lightly sand and recoat with the same stuff this fall before we launch for our annual trek south.

We grow barnacles like crazy here in our warm water but the most we ever got with the Ameron was some slime that wiped off easily. I probably only wiped the bottom down thoroughly half a dozen times in 2 years.

We used to use Trinidad 75 SR before but it's a hard epoxy type and just builds up over time. Ablative types are better in that regard.

The drawback to the Ameron is that it comes only in 5 gallon pails and you can only get through a distributor. It's intended for application on commercial shipping. We bought ours from an outfit in Jacksonville. It was about $85 a gallon back then. No thinning required, apply straight from the can by roller. Comes out nice and smooth.