I don’t know where the expression “On the Hard” comes from but it defines when the boat is out of the water and on firm ground. We were on the hard from November 20 until December 4, 2009. It was the first time since early June, 2007 that the boat had been out of the water. It is customary to pull a cruising boat out about every two years to have the bottom cleaned, sanded, and repainted.
The paint used is called anti-fouling paint. Unknown to me before my cruising life was the fact that marine growth attaches itself to anything and everything under the water. There are barnacles and slime that I see the most, all of which slows the boat’s performance in speed and adds to fuel usage. Under ideal conditions, clean bottom and prop, no wind, and no current, the boat will make 6.5 knots at 1500 RPM while using about 1.6 gallons of fuel per hour. Add a fouled bottom to this equation and the speed slows by one to one and half knots and the fuel usage can easily increase to 2.5 gallons per hour. Apply these figures to a relatively short passage of 600 miles and you can see why it’s important to keep your bottom clean.
Anti-fouling paint does not entirely prevent this but deters it some. Most of this type of paint is described as ablative. Once it is submerged in saltwater it starts to shed off at a predetermined rate. At one time a marine life poison was put in the paint call TBT, Tributyltin. This works great as a biocide but has been outlawed throughout most of the world as a hazard to marine life. My understanding is in the EU; officials can swab your paint and test it instantly seeing if it contains TBT. If it does you can expect heavy fines for bringing it into their waters. This law was put in place primarily because of large cargo and tanker ships because of their large underwater surface. A large oil tanker can have over 200 times the underwater area of a cruising boat but guess who the officials go after and who they ignore?
TBT is easily available here in Asia so while you’re guessing see if you can guess if I added a small amount to my anti-fouling paint. Because of our delay in going across the Indian Ocean until January 2011, our need to have a clean bottom when we do, and the need to have the anti-fouling done now, I chose to use a soft paint that will last about one year. This way we will have the boat pulled again next Nov/Dec, the remaining paint blasted off with a high pressure washer, and new, more expensive longer lasting and TBT free paint put on.
This picture shows the boat just after it came out of the water and before it was pressure washed. Note the barnacles on the propeller. That is Elizabeth from Larbarque looking with me.
In this picture the yard worker is taking a break so I picked up the wand and continued.
In this picture you can see the shine of the bronze prop which I have spent time polishing. I was told it would not do any good but my reply was that the barnacles would see their reflection and turn away. Actually I don’t think barnacles can see.
This crusted item is one of the many hull zincs in place to prevent corrosion to the hull by electrolysis. Most of the material was still there so I cleaned them some and reinstalled them.
These are the old and new zinc for the bow thruster and I did replace those.
In this final picture I am painting on the waterline stripe. The original was a tape but as you can see in one of the photos above, did not survive the pressure washing.