CopperPoxy - 11 year report

Bottom paint is often a discussion item among all boaters. From what we hear around the docks and anchorages, bottom paints/coatings/systems are about the second topic to come up. The first is anchors and anchoring techniques, and that takes on heated discussions similar to ones involving politics or religion.

It seems everyone has a brand or type that works for them. We are no different in that regard. We know that one type of paint might work very well in the Pacific Northwest and not at all in tropical waters. 

We have used a number of different bottom paints over the years and have found most to perform as advertised. That is, they stopped hard growth off of the bottom of the boat for a year or two. Some worked better than others. ALL have positive points, and ALL have bad aspects to them.

Originally I was not going to write up this report as I thought no one would be interested. Also, it seems that you can no longer get CopperPoxy from our original source, AMC. However, I have recently seen a number of threads on sailing and cruising message boards asking or talking about copper bottom products. After using the product on our cruising sail boat from the San Francisco Bay, down the West coast to Cabo San Lucas Mexico, and up into the Sea of Cortez, I think I can speak to how it has worked for us.

PLEASE UNDERSTAND, this is OUR experience with the product called CopperPoxy.

We make NO claims that it will work for any one else as it has for us. Having said that, we have photos to document all of our findings.

CopperPoxy is a mixture of about 40% epoxy and 60% pure copper powder. The copper powder in the mix we purchased was said to be 10 mil spheres. When applied to the bottom of our boat, it was to act as a bottom anti fouling coating and a barrier coat as well. It also made the bottom look like a shinny new penny.

In October of 1996, we applied CopperPoxy to the bottom of our Nor'Sea 27. We were in the San Francisco Bay area at the time. From the time we dropped her back in the water we were living aboard.

When we decided to try the CopperPoxy we were warned by MANY well meaning friends that it was just a lot of huey, snake oil, junk science. It seemed that everyone had something to say about the product. And very few had anything good to say. A number of people backed their negative comments with what seemed to be somewhat logical explanations.

We thought long and hard, but decided to take the chance. We have read that in the past, when ships were made of wood, many used to cover the bottom with copper plates. It seemed to me that we would be doing something similar. Also, at that time the cost of the CopperPoxy was about 30% higher than the normal bottom paint we were using. So, if it only lasted 2 or 3 years, it would STILL be less expensive. Not having to do even one extra haul out, with all the associated costs, would more than make up the small difference in the cost of the covering. If you look at the total cost for a bottom job, the paint is only a small part.

After we applied it, we dropped back in the water. We waited one year, and then had a diver carefully inspect the bottom. We then posted a “one year report” on it. Almost one year after that, we did a haul out to touch-up some areas that we did not do correctly the first time.

This is a photo of the bottom, still wet as we hauled out after 2 years. 

You can make up your own mind as to how well it worked as you look at the photo.

We then spent the next next 6 years sailing in and out of a marina in Redwood City, and Oyster Cove marina, all in the San Francisco Bay area.

In September of 2004 we hauled out at Svendsen's boat yard on Alameda Island, and touched up some of the CopperPoxy. We also added a coat of a water based ablative anti foul paint over the CopperPoxy. We felt that this would do some protection as we traveled into Mexico and when it had been warn away, it would then re-expose the CopperPoxy and it would then take over once again. Sort of a way to lengthen the life.

Later that month, we sailed out under the Golden Gate Bridge, turned left and started our cruising life.

In 2007, we determined that the CopperPoxy was no longer effective and decided to haul and do a bottom job.

We remember the CopperPoxy as a VERY heavy, weight wise, coating and we were not sure of putting another coat over the first. We were also concerned about the buildup of layers of epoxy. And we were not sure if we could get more of the product and get it to La Paz (where we had the boat at that time) in time to do the bottom job and head back out as we planned to do. So, in preparation for this we got 2 gallons of Pettit Ultima SR in red. I (Greg) was doing a delivery of a power boat from the San Francisco Bay area to La Paz, so getting the Pettit back down to La Paz was easy.

Guenevere was hauled in May of 2007 and the yard started a through pressure wash. 

It was obvious that some areas were starting to have hard growth. As the pressure wash was continued, that hard growth fell away. Near the boot stripe, were we applied extra CopperPoxy, we could start to see a bit of the bright metallic copper color coming through. On the sides, where the CopperPoxy was the standard thickness, or thin, the bottom of the boat, gel coat, started showing.

Now for the surprise! There was NO metal copper remaining in that area. It had all leached out of the mix. And, an even bigger surprise, with the 60% copper gone, all that remained was something like a sponge of epoxy. As the high pressure water sprayer worked this remaining thin epoxy sponge was also removed! What remained was the clean fair bottom!

I did not need to worry about an excessive buildup on our bottom! (hindsight is grand)

We had an uneventful haul out and applied ALL 2 gallons (a lot for a 27 foot boat) of the Pettit. We then went into the Sea of Cortes. Within 2 months, we had hard growth all over the Pettit! All during the summer I had to clean the bottom every 2 months or so.

On our next haul out we plan to procure a substitute for the CopperPoxy and reapply that!

Greg & Jill