Sunday, July 19, 2015

First Haulout

2.5 years after our launch, we finally had to get around to our first real haul-out. Even though we were probably about half a year over our planned dry dock interval of two years, things below the waterline were generally good. The massive hull anodes were in fine shape with signs of actively working to protect the boat, but only 10-20% used up. Even the smaller anodes on the rudder and around the prop were good enough to clean up and re-install. The zinc collars on the rudder shaft and prop shaft were definitely due, and the keel cooler anodes were all gone (including the bolts!). I had actually discovered this a few weeks prior when doing an inspection dive of the boat. This is what put the dry dock at the top of our priority list. The keel cooler anodes will definitely be an "every six months or less" inspection item going forward. The keel coolers were in good shape with no sign of wastage, so I guess we got to these in time. I also discovered that when I was testing the coolers in the rush to get the boat ready for launch in 2012, I had forgotten to replace the temporary brass drain plugs with proper bronze alloy plugs. Regular brass underwater deteriorates very fast, acting like an anode as all the zinc in the brass is removed through galvanic action. This leaves the brass very weak and spongy. We got to these just in time too. Otherwise a pretty standard haul out, with some basic bottom spot prep and prime and a couple of coats of good commercial ablative anti-fouling paint. Bay Marine in Richmond did a very nice job for us, and showed us all kinds of hospitality while we were "living at the ship yard" for the week of our haul out.

We decided to go black on the bottom paint color this time. This will give us a good indication of how the new paint is wearing- If we see the original red starting to coming through, we'll know that the latest bottom paint has ablated away and it's time to re-coat. With all the interior work we've done on the boat (and gear we've brought on board) the boat was trimmed down a bit in the stern. To keep the topsides clean from growth when fully loaded with fuel and cruising supplies, I raised the bottom paint from mid-ships back to the transom about 4"- something I've been wanting to do since we launched the boat.

Another item that I knocked off my to do list was a re-pitch and balance of the prop. We were generally cruising at 7.5 knots (our "economy cruising  speed") at around 1800 rpm or so. I had 2" added to the pitch of the propeller, making it a 34x26 prop. Now we get our target cruising speed at a slightly more leisurely rpm of about 1600 or so. This feels just about right now, and the exhaust temp shows us that we are still loading the engine correctly to keep the machinery happy. 

Keel cooler with new zincs anodes.

Hull anode- still in good shape.

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