1969 B32 keel/CB # 26.
I am in the process of rebuilding my Centerboard cable and pulleys in the trunk and would like some input.
System failed this year (two months ago). 25 years ago the same thing happened, or at least I think the same thing happened. My dad had the yard do the work at that time. Dad has passed on a few years ago. I did not see what was involved at that time for the repair, but was told the cable came off the shielded pulley in the trunk and jammed. I'm sure, at that time, the cable was replaced and pulley fixed or replaced. The system is and has held up well in 25 years from the last repair. I use it every time I go sailing. This year when I was raising the CB the pulley let go again, I was 90% sure, and it got very hard to raise, so I did not force it. Left it in the 1/3 way down position for the rest of the year and let the yard know of the issue to take care when hauling. They hauled it this week. I got to look at it yesterday. CB is still there, yay! That’s a good start. I was able to look up in the trunk and did see the sheave sitting loose on top of the board. I am lucky I did not lose it. I proceeded to take it apart. Hoping I can do this repair without removing the CB. I disconnected the cable from the winch, removed the pulley, block and wood mounting base off to expose the top of the cable tube that runs through the cabin. Unscrewing the tube from the access plate on the top of the trunk, it was way too easy to get free. Tube looks like chrome covered brass. I will get it chromed again. I took the service plate off the top of the trunk, and that too went way too easy. I found two pulleys attached to the underside of the plate. Both pulleys mounts will need replacing. One of the pulleys had fallen off and was wedged on top of the CB in the trunk and was starting to show signs of damaging the trunk walls. Good thing I did not try to force the CB up. I will post pictures of this repair.
I have a few questions if anyone has done this work:
1. Does anyone know of any other thread covering this repair? I searched the forum but could not find any that covered this size CB or configuration.
2. Looks like the access plate and pulley supports are made of bronze, and pulleys and pulley pins are made of stainless steel. How do I identify what the plate is made of? Edit/Answer:
Looking like Navel Brass and I'm going with 3" Fiberglass reinforced Nylon Sheaves and Naval Brass pivot pins and Naval Brass retaining pins for picot pins.
3. Damage looks like indifferent metal corrosion damage (Galvanic Corrosion). See pictures. I was wondering if the yard, when fixing this issue last time, changed the original sheaves and pins that were maybe bronze as well with the SS ones. I researched and can get in bronze. Any down side to using bronze? The deck pulleys for this system are bronze. http://www.fastenal.com/content/feds...0Corrosion.pdf
4. Anyone know someone that can fix the brass supports for me for a reasonable cost? They will need to be cut off and new ones wielded on. Someone in the North East USA please. Edit/answer:
I was able to order the Naval Brass C464 parts cut to size. Order Brass, Nickel Silver Angle, Ball, Hex, Metal Pack, Pipe, Round, Sheet, Square, Tube Alloys , , 230, 260, 330, 360, 385, 770, 792, Brass in Small Quantities at OnlineMetals.com
and will be electric brazing (50,000 lbs psi) this myself.
5. What can I use instead of SS wire rope for cable? Although what I have seen in other threads is people have had issues with the cable braking. The cable I have now after 25 years is not showing any signs of letting go, but I have not been able to get a good look at the cable connection to the CB. Next time I go to the boat I will get pics of this connection. Edit/Answer:
20'x3/16" Stainless Steel 316 7x16 wire rope with an oval SS 316 Swage, 3700 lbs BK and 760 lb WL rated. I am estimating the, 16" at the widest part and 6'-6" long fiberglass, CB weighs 60 to 80 lbs and has two 8" round led or zinc counter weights towards the bottom end and a 1" naval brass pivot pin. I was going to use Amsteel, but I was not keen on the UV issue, my cable is exposed to UVs and I liked the 25 years I got out of the last SS one. Details can be found in plans I am putting together to document this setup.
6. Can I replace this cable without removing the CB? I will try to get access to it by raising it by hand and blocking it up and access this from the access port on top. As you will see in the pics that the sheaves and supports are about 4” tall and the slot is only like 2” wide. Not sure if that is enough space. Or I could do the whole repair, button it up and leave a snake wire in place of the new cable, wait for the yard to lift boat for launching in the spring, swing the CB all the way down. I think I will have access to the connection at that time. I would prefer to not do the latter or remove the board. Edit/Ansewr:
Yes, cable can be replaced in the all the way up position and the all the way down position.
7. Looks like the yard made their own rubber gasket for the access plate, I will do the same. What material should I use? And what caulking to seal rubber to bronze and rubber to fiberglass? 5200? Edit/answer:
I will be using 3M 4200 without rubber gasket.
Thanks in advance for your help.
Edit: Looks like the entire repair will cost just under $200. And I should never have a sheave issue again. I will inspect the Amsteel yearly and report back on it's wear.
If you want CAD files or PDF: https://drive.google.com/file/d/0B_d...it?usp=sharing