Monday, October 4, 2010

Chain plate bling bling

We made it out of the grip of Earl and started right away on the projects that we left behind.

The list number two.

You'll make 10 or more lists for every list, so don't let the list rule your decisions. Things change, new ideas pop up in the shower and there's hours of conflicting advice if you spend time at the bar.

Chain Plates - these are the stainless steel plates that connect your standing rigging to the hull of your boat. Usually they pop up above the deck with turnbuckles attaching them to wire or rod rigging... and they usually look nice and shinny. BUT, if they're more than 10 years old or you don't know how old they are you MUST replace them... or at least remove them and acid test/x-ray them to confirm in your mind that they are solid and won't go bang when you least expect it. Chain Plate failure usually results in the mast and rigging coming crashing down if it's under load at the time, and I've seen beautiful looking chain plates pop under surprisingly little pressure. While you're at it, replace the nuts and bolts and re-bed them with a good bedding compound... you'll sail happier and safer because you did.

New chain plates cost from $300 to $500 each, depending on their "trickness" and how polished you want them. If yours are flat you can make them with a bench drill and some good quality stainless steel plate... just make them strong and polish them up as much as you can... this helps avoid corrosion.

Odessa's chain plates are simply attached... don't look at the rub rail, that's on list 15

The chain plates on Odessa were quite "trick" with double layered sections, bends and turns so... without a major machine shop in our luggage, we had to have the new ones hand made. After asking around and visiting a few fabricators, we found just the perfect place and person for the work... Peter Durkan of E&MSC at Lagoon Marina St. Maarten.

I'll skip the part about removing the chain plates because every boat is different, and I could rant for pages about boat builders only building boats for the original customer... who will own it for a few years and pass on the long term maintenance. Needless to say, removing can be quite a challenge with bloody knuckles and bruises where you don't want them.

This was the easy one!

Devon gets the easy side!

So, Peter acid tested our chain plates and they looked good... well, for about 3 weeks sitting on the bench. But slowly the rust residue began seeping out of microscopic cracks in the bends and where two pieces of plate had been welded together. The next test was to put a welder to them and sure enough they spat like a bugger... welding stainless requires a perfectly clean surface, so this was another indicator that there was corrosion inside the metal. That's the thing with stainless steel, it looks all shiny on the outside, but it's the inside that's important and where the damage happens and you never know if it'll give way.

NOTE: Odessa has a fiberglass hull which is curved and the chain plates follow the curve. The builder had welded two plates together with a slender cone tapering down to the bottom so that the lower half would bend slightly and conform to the curve of the hull. Now Odessa is 26 years old and new fiberglass will move under loads until eventually "setting" after a couple of years. So due to her age the hull was "set" and the slight flat spots where the chain plates are will be there forever... we'll until we fair them out and paint the hull.

So we didn't need the thinner plate and in fact the old plates perfectly showed the curve of the hull, so we just used heavy plate and slightly bent it to the shape... heavier, but stronger, and no welds to weaken the plate.

This job was a family affair and even in the heat we worked as a team... I was very impressed. Anyone who lives aboard a boat knows that the simplest job involves the tightest spaces and usually takes 5 times longer than expected. But it's worth it and even though it's tough to get the kids to help,.. once the whining is over, they get a lot of satisfaction and are proud of the results.

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