dropping a centerboard

beamreach · Mar 16, 2009

Justin: I have a '93 model. I have not dropped my centerboard but think I know the steps. Mine has 2 fiberglass plates about the size of 6 inch deck plates. One is located under and forward of the sink area. Not a pleasant place to reach if you are oversized like me. I removed it once to re-seal it and could with a flashlight see the bolt.Another under a cover plate in the cabin sole near the door going to the head. These plates cover holes that will give access to both sides of the centerboard bolt. I imagine it would be a 2 man job to get the bolt out, since one would be working under the sink area. The older 26c's had access to this bolt from under the boat. You have to have a bent wrench to access the bolt on those. I don't know when Macgrgor changed the process but if you have the interior plates as descibed above, your boat is set up like mine. Good luck.

Doug J · Mar 16, 2009

What style do you have?

My 91' has SS brackets on the outside of the hull.
I replaced my CB with one from Idasailor.
Once you have the boat lifted and can drop the CB, here's what you do.

1) remove the two plastic plugs that allow access to the nuts inside.
2) use bent 9/16 wrench to reach inside to the nut, loosen and remove both sides.
3) remove nut and bolt from the end of the control cable.

Reverse procedure to install. I used a little silicone on the plugs, just to make sure they stay in place. Other than that there is no need to seal anything. The little compartments inside where the nuts are is isolated from the inside of the hull.

I replaced the cable on mine with good quality low stretch yacht braid, and just put a stopper knot in the end. The original cable, nut and bolt arrangement is very abraisive to the CB. I think the yacht braid will be a lot easier to replace when the time comes.

Doug J · Mar 16, 2009

Yeah, I think they stopped selling them. I believe it was something about how many they could get out of a single sheet of hdpe, they wasted too much material.

Can you post pic's of your job as you do it? I've read a lot of posts about the style that has the access plates inside the boat, but I've never seen it. I'm sure this question will come up again in the future, pictures will come in handy.

beamreach · Mar 16, 2009

Justin: Looks bad on the surface, but I think this could be a not so hard fix without removing the board. Get a putty knife, mix up some Marine Tex and force as much of it into the damaged area as possible and more outside. Then take a strip of masking tape, cover your repair (the wet marine tex) and shape it with your hand to conform to the shape of the leading edge. Give it 24 hours and pull off the tape. I think you will be pleased with your repair. No sanding. I've been there with worse looking damage than this and this procedure worked great. If it doesn't work your're only out a few bucks, and if it does, you've saved yourself a bundle.

Doug J · Mar 18, 2009

Ida CB

Justin, did you happen to find out if they would provide a lifetime guarantee like they do for their rudders?

Also, I believe you can get a Macgregor replacement CB from BWY, for a lot less $$$.

walt · Mar 18, 2009

Justin, funny reading the thread you found... I did rebuilld my centerboard and it was a real saga (story below). I had talked to Idasalor in the past and they always needed some minimun number of people to buy before they would get the material to build or do a production run (which means you will probably never get one from them). Maybe they changed policy and bought the material in advance and will now make you one?

My centerboard story - finally with a happly ending. Thinking my centerboard might have had the wood stringers rotted since the boat spent a lot of summers in a slip (which I have no idea if they were or not), I pulled the centerboard out, cleaned the hollow inside as best as possible and poored a bunch of polyester resin (which I tested to be more dense than water) in both the top and bottom sections of the centerboard with the idea that even if the internal stringer was somewhat rotted, the resin would seal the stringer and to some extent become the new stringer and also keep any new rot from happening. Even after the resin, there is still some hollow in the centerboard but only near the trailing edge. I also added a couple layers of glass and epoxy on the skin, improved the shape a little (had some flat spots, ect) and also beefed up the pivot hole which had a structural crack in it with a brass insert epoxied in.

I did this over the winter and first time I tried the new beefed up centerboard, it would not drop. I pulled it out and found that there had been some mud inside that ended up sealing in some air pockets when I put in the internal resin. So I got rid of the sealed air pockets and made sure the centerboard sank on its own - it did. Put it back in the boat and it still would not drop down. Took it out again, sanded some more, put about 6 pounds of lead in the bottom. Dropped down about 1/2 way now, but still not all the way. When I went sailing, I used a rope around the outside of the hull to pull the centerboard all the way down. I think I may have taken the centerboard out, sanded, then put it back in one more time.

Finally, last fall, I filed down an area very near the top end which fits up into the bunk. This spring, the damn thing FINALLY drops down no problem. Its a huge luxury at the moment to be able to raise and lower the centerboard!! Im also pretty sure that the centerboard is not going to break now..

So now, Im a master at raising the boat off the trailer and getting the centerboard out ( my 1990 is similar to Dougs - but the access holes on the hull bottom look way more beat up).

I think your hole should be easy to fix. The marine tex idea should be ok and you could possibly build up the missing area a little with epoxy and glass chop before puttng the marine tex as the final layer. Looks llike that is the area where the centerboard rests on the V shaped bar on the trailer which keeps the centeboard from droping.

walt · Mar 18, 2009

Epoxy would be very expensive to fill the centerboard - plus it would not flow very well. I used polyester resin on the inside mostly because it is a lot cheaper and generally "thinner" before it sets up. Epoxy would be better mechanically. Either way, you have to worry about doing too much at one time as things can get VERY hot.

However... Im not sure how much acetone you can add to epoxy and still have it set up (after the acetone evaporates) but maybe clean up the inside real good. The stringer runs from top to bottom (ie, the stringer is about 6 foot long) and forms a chamber on the leading edge and a seperate chamber on the trailing end. Maybe pour about a pint of acetone thinned epoxy in one section making sure everything gets wetted out and sit so the epoxy soaks and hardens on the stringer, then do the same for the other chamber? I got rid of some of the holes on my centerboard - but it ended up causing a lot of grief so Im not sure this was a good idea.

Doug J · Mar 18, 2009

Good to know

Justin_NSA said:
Good story Walt. I was thinking along the same lines of finding some way to inject epoxy to fill the voids and then fill the hole in. Is it possible to do that? Would other holes need to be drilled in other strategic areas to get complete coverage?

Doug, IdaSailor said the centerboards come with the same lifetime warranty to the original purchaser as the rudders.

Thanks for checking on that Justin! That's good to know. I spent a lot of money on mine if it ever breaks, I'll have peace of mind knowing I can go back to Idasailor. One things for sure they stand behind their products.

Have you checked with BWM to see what a replacement Mac CB would cost?

Doug J · Mar 18, 2009

There ya go!

Sumner · Mar 18, 2009

Justin_NSA said:
Unless IdaSailor can come close to BWY's price on a new centerboard I think I'm going to buy one from them. BWY wants a liittle less than $300. :dance:

Their catalog distinguishes between 2 different setups that occurred during the middle of '92. One has a larger pivot hole for models with external pivot brackets and one with a smaller hole for internal mounting like mine.

I posted the following the other day on the MacGregor/Venture forum on Trailer Sailor. You will see that Ida explained to me why they no longer produce the centerboard,

Sum

====================================

I just got off the phone with an Ida Sailor service guy who really took the time to explain their rudder history and so forth. While it is still fresh in my mind I thought I would write it down and I think the following is accurate, but if in doubt call them.

First the material thickness they need for the rudder is 1 3/4 inches. I talking to him he knew I had a Mac S, so this might be different for a different Mac or Venture. He said they can't always find material in that thickness so they have had different solutions.

1. Their first solution was they got two pieces of material and made the "entire" rudder from the two pieces with one being one side and the other the other side. These were then welded around the entire circumference. A great number of these failed and were replaced under warranty.

2. Then they made the entire rudder from one piece, but since it wasn't thick enough where it attaches they made a "shim cheek" plate to go in the area where they pivot. Initially these cheek plates were welded on all four sides. The bottom weld then caused a stress prone area in the area that was also the highest stress point on the rudder. Some of these failed and were replaced free. If you are having a hard time visualizing the stress point hold a long envelope between your tow palms with the envelope stick out past the bottom of your hand. Now have someone else grab the bottom of the envelope with their two hands and twist. The bending, stress, is going to happen right below your hands. Your hands are the rudder attach assembly trying to turn the rudder one way while the other persons hands are the water pressure, drag, trying to resist the turning.

3. The next version welded the cheek plate on only the top and the two sides. Well these worked better, but sooner or later some of the welds on the cheek plates wanted to crack and the cheek plate would separate. Owners then started just screwing them back on. Ida Sailor then followed suit and screwed theirs on as this plate is just taking up the space needed to get the rudder to a 1 3/4 inch thickness at the pivot point. This is the latest version the way I understand it and is what I have.

4. Some rudders required a check plate to be attached to both sides to get the 1 3/4 inch thickness and others only on one side (ours is that way).

5. Finally some rudders don't have the added on cheek plates as they were able to obtain material that was 1 3/4 inch in thickness or greater to begin with.

There you have it. Now one thing he told me that made me feel a lot better is that they feel these rudders have not just failed with no warning if they had been periodically checked. He said to periodically check you rudder in the area where they have failed....

..........for any hairline cracks or stress marks. If you see them then you probably should be getting new rudder or make sure you have a spare with you. He also said that they felt that most rudders failed at some point "after" being stressed such as running into or damaged such as the tide going out and the boat sitting on the rudder or something that then start a process of stress cracks growing to the point of failure. Check your rudders.

I mentioned drilling a hole into the other end as a solution if the rudder did fail. He felt that it was easier to get a 2 X 6 or larger piece of wood and just rough shaping it a little and drilling it so that it could be mounted in an emergency to get home. I think I'll do this. He also said that you can fix up an old oar or paddle as and emergency rudder.

I felt that he was very honest with me and faced up to past problems and I believe him when he said that the present failure rate is very small. I can't remember for sure, but I think only a couple percent and he felt that their rudder was much stronger than the stock one.

I feel good about things and will make a simple "get home" rudder by drilling the other end like Chris did and will check my rudder for stress marks and quit worrying about it.

c ya,

Sum

Doug J · Mar 19, 2009

Sum, I read your post previously on the other BB, and read it again here. Maybe I'm missing something, I don't see the explanation why they no longer produce the centerboard?

Sumner · Mar 19, 2009

Doug91Mac26S said:
Sum, I read your post previously on the other BB, and read it again here. Maybe I'm missing something, I don't see the explanation why they no longer produce the centerboard?

Since they would have to sell it for about the same as the rudder, which is a lot more than BMY wants for their centerboard they don't see a viable market. The guy told me that their centerboard doesn't offer any real advantage in performance over the stock one, so why would someone pay considerably more for it.

That isn't the case with the rudder as their rudder is significantly better in performance that the stock one.

c ya,

Sum

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Doug J · Mar 19, 2009

When I bought my CB in 05', of course Idasailor did have something to say about the added advantage over the OEM CB, foil shape etc. I liked the idea of it not being hollow, thinking I would never have the interior rot issue to worry about again. If I recall, I paid around $450 for it.

dropping a centerboard

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