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Rudder Rebuild: The Shaft Part I

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As you might recall, we lost a rudder while at sea crossing from Minerva Reef to Tonga – it was an utter rudder disaster.  We managed ok for over 1,000nm with just one rudder before we were able to get our hands on a temproary rudder which we then had custom fit to our boat.

But it is time to replace both rudders now that we are in New Zealand and the boat is hauled out.  We researched many different options including having Jefa Rudders custom design them from the UK; a boat builder in Auckland, NZ;  Foss Boatbuilders in Los Angeles; and considered having Norsand Boatyard do the work. There were pros and cons with each company, so we decided to hire local professionals that we had first hand knowledge of their expertise and skills.  They had already worked on our boat and had years of glassing experience.

The Rudder Shaft

The first thing we have to do is design and build the rudder shafts (or posts).  Technically, both of our rudder shafts are “in tact” but the tines or fingers on the port shaft are damaged.  At the top of the shaft you will see a ring and one tine sticking out.  This is the front of tine and there is supposed to be a back.  The middle tine is broken half way in the front and has no back portion and the bottom tine is completely gone.

Damaged Rudder Shaft with broken tines

Damaged Rudder Shaft with broken tines

We engaged our friend Rob at RH Precision while we were still in Tonga.  We love Rob!  He has done several stainless projects for us and is just a gem to work with!  He has all of the fun tools and machines for welding stainless and aluminum.  Matt finds the dimensions and all of the measurements to our existing rudder shafts (thanx to the Catana Mailing Group and several other Catana owners who shared their specifications).  

We triple check all of the measurements with our existing rudder shafts (both the damaged one and the one that is still in tact).  And then we double check them again.  Matt specifically orders 6082 aluminum (from High Grade Metals in NZ) which is stronger than our original lighter aluminum.  Rob works his magic and expertly replicates our rudder shafts as per the diagram.

Bigger is Better

Rob then drills the holes. There are 4 holes near the top which is how we connect the post to the boat and 4 holes for the tines.  We decided to go with 16mm tines which are bigger and stronger than our current 14mm tines.

I assumed Rob would be able to do the tines as well, but I was wrong.  We had to get the rods for the tines…hmmm.  Rob sends us to Vulcan Ullrich Aluminium in Whangarei where we are able to purchase a 5m of 16mm rod.  We have them cut it into (8) 280mm pieces and we take the almost 4m of extra rod back to Rob as a gift.

The Final Steps

Rob pounds the 8 pieces into each hole for us and then we take it to Absolute Stainless to tack them in place so they wont move (tack weld).  Yep, this is a process.  It doesn’t take long to tack weld them as we were able to pick them up the next morning.  The next step is to have the rudder shafts anodized.  So, we drive them to Auckland (2.5hrs each way) to Alert Anodising where they will put 25 micron hard black to protect them.  We had wanted marine grade but evidently there was a mix up. Rob assured us it would be fine and that this was still very good.

10 days later we make the drive back to Auckland to pick up our newly anodized rudder posts.  

The shafts look so sexy!  I am not sure why I think they look sexy with the anodizing, but I do!  We laid the new shaft next to the old shaft and what a difference.  The new shafts are about 27cm longer and weigh almost 1 kilo more than the older shafts.  Compare the damaged shaft to the new one on the right photo.

Now we are ready for the blades.  Stay tuned for part II of the Rudder Rebuild.

Our blog posts run 10-12 weeks behind actual live events.  This blog post occured during November 2023.  

The Low Down on Coppercoat Antifouling: Part II

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In our last blog post we started the process of preparing our boat for new antifouling.  We typically used paint, but technology has changed and the better choice for protecting your boat’s bottom is coppercoat.  We ran into some problems and the original blog post grew too long so we broke it up into a few posts.  Here is part II.

Coppercoat

We ordered the coppercoat directly from the NZ coppercoat contact.  We ended up ordering 20 one liter kits which contain part A and B and the copper) and an additional (2) one liter cans for us (for any future repairs).  The reason we orderd one liter cans is because the coppercoat has a very specific application process and ordering it in larger quantities like 10L or 20L cans makes it very difficult for the team to apply it fast enough before it sets. You only get about 20-30 minutes to apply while constantly stirring your paint tin.

First the team, and yes, I mean “team” as 5 Norsand guys bring the supplies.  They set up a make shift table to lay everything out.  The 20 kits (each has 3 parts), 15 buckets, 15 paint trays, 15 rollers, 5 small rollers, tons of rags, turps, and gloves.  So much plastic.  The Coppercoat sets so quickly that they cannot reuse the buckets, trays, or rollers for more than a few coats.  Everything moves at warped speed.

The preparations continue as the team (Aaron, Josh, Conor, Ian, Luke) tape off our saildrives, rudder bearings, transducers and other vital parts that can’t be covered in coppercoat and need protection.

The Application

The boat is washed down with ISO to remove all dust particles and then the magic begins.

Our chemist, Josh begins the mixing process.  He is dedicated to mixing each kit and keeping the painter’s trays mixed so the Coppercoat doesn’t set too quickly. Aaron (far left) is the yard manager and is supervising before starting the painting process.

The 5 guys work straight through lunch for over 5 hours applying 5+ coats, evenly, consistently, and professionally along our hulls.  It was exhausting work but they powered through and completed the job!  We were so pleased that we had a little happy hour celebration under the boat.

The first coat (top), the 3rd coat (middle) and the final coat (still wet).

I must be honest, I am not a fan of the color (copper) but I am even less pleased with what the color will look like once it spends 4-6 months in the salt water and oxidizes. And this is the permanent color for the next 10 years.  These are not our boats (obviously), but it will give you an idea of what Coppercoat looks like once it has oxidized in the ocean.

Prop Speed

The coppercoat sets as we are finishing up a few other boat projects.  One of the final projects is preparing the saildrives and props.  We sand them down, apply a barrier coat to the sail drives (the white paint), sand down the props one more time. Then it is time to apply prop speed which helps prevent growth and corrosion on the sail drives and props.  The bright yellow sure clashes with our copper bottom – oh well.

Activating the Coppercoat

It seems so wrong, but this is the process.  The yard comes in a few days before we splash to burnish (sand down) our beautifully painted Coppercoat.   Jamie uses 320 grit sand paper to activate the copper – but it was really hard to watch them burnish the new bottom job.

And that is the Coppercoat process.

Did you miss Part I of “The Low Down on Coppercoat Antifouling?”  Our blog posts run 10-12 weeks behind actual live events.  This blog post started in early November and finished around the end of November.

The Low Down on Coppercoat Antifoul: Part I

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One of the most expensive boat maintenance projects is the bottom paint.  For the last 13 years we have been using Sea Hawk Island 44 bottom paint which requires a new application, hauling the boat out every 2 years, and endangering the oceans we love.  The paint is expensive, the sanding and prep are expensive and the haul out is expensive.  but it was a necessary evil. That is until we decided to go with coppercoat. 

Coppercoat

Coppercoat is considered a more environmentally responsible choice for antifouling.  It is a combination of a solvent free water based two part epoxy resign and high purity (99%) copper (it is not paint).  Each liter of resign is packed with 2 kilos of ultra fine copper, the maximum allowed by law, making it the strongest copper based antifouling available.

This product is tin free, non-leaching and much kinder to the ocean than conventional self-eroding anti foul paints.  The complete treatment has been approved by Health and safety in UK and EU and complies with International Maritime Organization.

Benefits 

Even though the initial outlay of money is more expensive than one time haul out and bottom paint application, it lasts for 8-10 years.  So, that is one application vs 5 applications.

It is a lot more environmentally friendly, leaves a smooth surface, and requires the same if not a little less maintenance.

And its repuation and claim shows excellent results.

How does Coppercoat work?

Once in the water, the ocean attacks the exposed pure copper, causing the formation of cuprous oxide. This highly effective anti-fouling agent deters growth until the surface degrades further to become cupric hydrochloride. This final copper form is highly unstable, and is washed away by the movement of the yacht, thereby removing any accumulating silt or slime. This automatically reveals a fresh copper-rich surface whereby the process recommences.

Here is a condensed version of the process:

  1. Sand the bottom of the hull down past the barrier coat
  2. Apply new barrier coat or primer
  3. Sand primer
  4. Clean with MEK to remove all particles 
  5. Apply Coppercoat (5-6 coats in one sitting)
  6. Sand to activate coppercoat

Primer / Barrier Coat

We went round and round with what type of primer to use.  There are several choices and frankly I am not sure there is a clear proven “winner” or better choice.” 

Choice 1 – Water Based Epoxy

Several cruisers that we know used a water-based, solvent-free epoxy primer (such as Hemple).  Their thought process was that the water-based expoxy primer would stick better to the water-based coppercoat.  Makes complete sense and is very logical.  The problem is that these types of primers do not go on flat.  They create peaks and valleys which then have to be sanded down making it very difficult to get a smooth surface which is required for the coppercoat application.  In addition, they are almost twice as expensive as solvent-based primers.

Choice 2: Interprotect Epoxy

The Norsand boatyard recommended Interprotect High Performance Epoxy Primer which is a solvent-based epoxy primer that has been in the marine industry for over 10 years.  The application process is proven to be effective, is applied evenly, and adheres to coppercoat .  The downside is that it requires two weeks to “off-gas” before the coppercoat can be applied.  You know the saying…time is money?

Choice 3: Coppercoat Barrier

The NZ contact for Coppercoat had his own version of primer which he recommended, CK4261 Ceramic Barrier Coating.  However, the yard has had poor results with this primer and recommended we use Interprotect.

I also contacted Coppercoat headquarters, Europe and asked for their advice.  I gave them the pros and cons of all three variations.  They said the good news is that coppercoat will stick to anything.  But the bottom line was “use what the yard is comfortable with as they are doing the application and have to stand by the end result.”  That resonated a lot with me.

Primer Winner

We ended up using Interprotect (what Norsand recommended) 27L of Part A, 9L of Part B and 4L of thinner.  Ian and Conor applied 6 coats with the first three being white and then they added pigment to make the last 3 coats a light gray.

The overall effect was actual rather nice. 

Final Adjustments to Previous Repairs

Once the paint dried we found a few areas that needed more filler.  Look for a slightly darker color and or indent in the photos.

It is hard to find these problems when the boat is white and gray but now that it is all one color we could see the imperfections.  So, they get filled (wine colored paint), sanded, and recovered in barrier coat.

There is too much for one blog post so tune in for The Low Down on Copper Coat Antifoul Part II coming up next.

Our blog posts run 10-12 weeks behind actual live events.  This blog post occured around mid-November.  In our last blog post we take Sugar Shack down to the bare bones.