The Blue View - Chainplate Update

We are finally making some progress on the chainplates, although it has been one step backwards for each two slow steps forward. The most recent setback was when I discovered, after the stainless for the chainplates was all cut, drilled and polished, that the metal for the backstays was the wrong thickness – 3/8” (10mm) instead of 1/2” (12mm). We will lose another week while they are redone. wrong size backstays

There are two bends that need to be made in each chainplate, but determining the location of each bend has to wait until the part is attached to the hull. Once attached, the precise location and angle of the first bend can be measured and marked, then the chainplate must be removed and taken back to the machinist to be bent. Next the parts will be reattached to the hull, the second bend measured and marked, and again sent to the shop to be bent. All this has to wait until the holes have been drilled in the hull.

chainplate attachment

Most of the holes in the hull have now been drilled, which was a major undertaking. A total of 68 holes needed to be drilled, most of which pass not only through the hull, but the old stainless chainplates as well. All but eight of these have been drilled, and these remaining holes will wait until the first bend is made and the chainplates reattached. One thing we noticed as the holes were drilled was that rust colored water continues to seep out from the old chainplates – continued confirmation that we are doing the right thing here and didn't wait any longer.

holes in the hull

The exterior carpentry is done. The last phase was fabricating and attaching the teak spacers to the hull, and this has now been completed.

attaching the teak spacers

The interior cutouts have all been made, luckily, except for one in the forward berth, they are all inside bookshelves or lockers. I used my Ryobi version of the Fein tool to make the cuts. I will make teak pieces to cover the holes – a few in the next few days with the teak I have on hand and some later when I can get  less expensive teak elsewhere. I want to be able to easily remove the hole covers later so that the new chainplates and bolts can be inspected periodically.

interior cuts

Progress is being made, although painfully slow. Maybe another week until the project is complete – assuming no more major setbacks. Using Marcie's project formula, it'll be another two weeks.

The Blue View - Chainplate Update

We are making some progress on the new chainplates. Now that the metal has been cut, the machinist  came down to look at Nine of Cups and take some measurements. Sort of like “Ready, Fire, Aim...” in my mind. There was some initial angst when we thought the chainplates had been cut too short, but after talking it through with the shipwright and with Dave, we all agreed the newly cut metal would work. will the metal work

The marine architect made an appearance as well. He did the original design based on photos, assuring us that he knew the boat quite well and that a trip to the yacht club to actually look at Cups was unnecessary. This was borne out, as you may remember, when his first iteration of the design was totally incorrect, having the chainplates bolted to the bulwark and into the core of the deck. We had a discussion, now moot since the metal was already cut, about how the chainplates might have been designed to look less industrial and more aesthetically pleasing. He gave us several less than compelling reasons why this wasn't done, such as “it would have added extra weight to the boat” (two pounds in extra metal would make a difference on our 21 ton boat?), “designs that bolted the chainplates into the bulwark wouldn't be as strong” (not something I was suggesting, and anyway, wasn't that exactly the way he first designed it???), blah, blah, blah … We weren't really impressed.

exploratory hole

The shipwright came shortly after, and following much measuring and discussion, he drilled a small exploratory hole through the hull to determine how thick it was and where the bolts would protrude into the interior. When the bit came into contact with the old chainplate, water started running out of the hole – maybe  a teaspoon or two. If water had made it that far into the hull, approximately two feet down from the cap rail, it was almost certain that the old chainplates would be suffering from crevice corrosion – more confirmation that we were doing the right thing. Another small hole was drilled alongside the chainplate, and no water came out, some assurance, at least, that the water ingress was confined to the column alongside the chainplate.

water in the hull

We are now waiting for the machinist to drill the holes in the chainplates and polish the stainless steel to a mirror finish, after which the hull drilling and cutting will begin in earnest. I sound quite negative, but in actuality, I am still optimistic that the project will turn out fine.

Stay tuned...

The Blue View - Chainplate Issues

The typical lifetime of the standing rigging on a sailboat is 10-15 years, while the typical lifetime for the chainplates is 20 years. We replaced the rigging in Colombia about 13 years ago, so it is now due to be redone. The chainplates, however, were never replaced, and are now well past their “use by” date. They are totally fiberglassed into the hull, making a thorough inspection impossible without removing a lot of interior  cabinetry and grinding out large sections of the hull. I routinely inspect the exposed portions, and while they never showed the least sign of internal corrosion or water ingress, I knew we were sailing on borrowed time. crevice corrosion

A few days ago, when I was doing our pre-passage rigging check, I noticed a salty, vinegar-smelling substance coming from the chainplate cover on one of the starboard shrouds – not a good sign. There was no doubt in my mind that it was now time to replace the old chainplates, and since the rigging was nearing the end of its life, I decided to replace it as well. In addition, if we were going to get everything done before our South African visas and the customs permit on the boat expired, we would have to hire the work out instead of doing it ourselves. This was going to be an expensive few weeks.

refit chainplate

Because it was not feasible to remove and replace the old chainplates, my plan was to attach stainless straps to the outside of the hull. Holes would be drilled all the way through the hull and the old chainplates, and the straps attached to the hull using bolts secured on the inside with nuts and washers. I've seen this done on another Liberty 458, as well as several similarly designed boats. If the straps are polished, the bolt heads countersunk flush, and the carpentry done right, the end result is, hopefully, not only be strong, but attractive as well.

Cape Town is a great place to get boat work done. They have an active boat building business, and there are hundreds, if not thousands, of local boats, as well as many more boats passing through, all of which support a number of skilled marine tradesmen. Once the decision was made to replace the chainplates, I wanted the advice of experts to make sure I did it right. I talked with the local marine services expert, who quickly contacted a marine architect (to evaluate and design the chainplates), a rigger (to  replace the standing rig), a stainless steel fabricator (to make the chainplates), a marine carpenter (to modify the cap rail, rub rail and interior cabinetry with minimal damage), and a shipwright (who will be drilling the holes). With all these experts, what could possibly go wrong?

Photos were taken and sent to the marine architect, and the various experts conferred with each other. A few days later, Dave, who owns the marine services company called to say the plans were done and the quote prepared. If I came by and signed off on it, we could get started. I checked the quote and the drawings, and thought the price was quite reasonable. But then I noticed there weren't enough chainplates in the quote – we need eight and there were only six in the quote. Dave thought about it, made a trip down to Nine of Cups, and agreed that the quote was wrong. He said he would get it redone and get back to me.

The next day Dave called again and said the quote was revised. I stopped into his office and looked everything over. The price, as expected, had gone up because of the added chainplates. In South Africa, as well as most of the world outside the U.S., everything is done in metric. I'm used to seeing things in millimeters and centimeters, but I still have to convert a dimension to feet and inches to get a feel for the size. While I was checking the drawings, I saw that they were 350mm long, and mentally estimated that that would be equivalent to about 13-14 inches. This just didn't seem long enough to me, so I asked for a copy of the drawing to take to the boat and make some rough measurements, just to convince myself everything was right. Sure enough, the chainplates were too short. Some of the bolts would have passed through the bulwarks instead of the hull, and two holes in each chainplate would have been drilled right into the deck.

Dave apologized again, and conferred with the marine architect who lengthened the chainplates and reworked the drawings. The new quote was considerably higher, and had yet another problem. The fourth quote appeared correct, but was just about double the first quote - not so reasonable anymore. I signed off on it and the stainless fabricator was given the go-ahead.

carpenter delivers the news

That was Thursday. Friday was a holiday, and on Saturday the carpenter stopped by. I told him about the lengthened straps, and he pointed out yet another problem. The hull has a small step just under the rub rail. It isn't obvious because the rub rail hides it. If the chainplates are lengthened, we will need a spacer behind each chainplate, which may or may not be a problem. Dave will need to check with the marine architect on Monday, and hopefully, the machinist hasn't started on the chainplates in case there is another change needed.

Other than that, everything is going just fine.