Centerboard mechanism Alden 44

[rapignataro]

Hello guys

I just bought a Alden 44 and I have a problem with the centerboard mechanism.
Has anybody an idea how it works and or drawings details and the access from the keel?
The hydraulic system is working fine but the centerboard doesn't move

Best wishes

Ronaldo

[unclemack]

Hi Ronaldo,

I've no knowledge of your particular system but do have questions.

Presumably a centreboard would suffer much greater damage in a grounding if held down by a hydraulic ram rather than just by its own ballasted weight.

To avoid that it might be built so that the ram lifts the cb positively but only allows the cb to descend under its own weight.
In other words the ram might move normally in cb down direction but not force the cb down.

Benefit is that the cb can kick up on grounding and is more likely to survive, downside is cb can easily stick in up position without that positive lowering force.
Just like a winched system really.

Just theory, sorry

Haven't much experience with centreboards except on dinghies but did once help an owner make some tools to clear growth etc. from inside the cb trunk.
He spoke of gravel having once jammed the board when he'd beached for hull cleaning.

Even heavy iron swing keels can be jammed by barnacles.

Look forward to reading how yours turns out

[rapignataro]

Thak you Unclemack!

The cb is a little bit down. It's not heavy, I can move it up by my hands but not by the mechanism. I can't see it and I don't know how to access.
Maybe it has hole in the keel, that's why I need drawings.

[BDZ123]

Hello all! I’m currently looking at an Alden 44 as a live aboard for our family for the next couple of years. I really love these boats, but the one we’re looking at has had the center board removed, presumably “permanently”, including (obviously) filling the hole in the hull/keel for the lifting mechanism, etc. My question is:
How well do they sail without the center board? Is not having it prohibitive, or does it simply make pointing less efficient?
we’re ok with a slightly decrease in performance, but don’t want to end up with a boat that doesn’t point at all and can’t hold a line.
Thanks so much for any thoughts!!!

[Jammer]

I had a Morgan 24, which, while smaller, had a similar hull design and a combination short keel plus centerboard similar to the Alden 44. The previous owner had sailed the boat without the centerboard (which had jammed). I fixed the centerboard and found that there was not a huge difference in upwind performance. There was some difference in leeway, not much else.


Centerboard systems, regardless of design, are maintenance intensive and prone to fouling. These problems are particularly acute for larger vessels as much of the maintenance must be performed while the boat is in the slings as there is not enough clearance to remove the centerboard while on the hard, and the board is ordinarily too heavy to be safely removed by a diver. We are shopping for a new vessel now and have ruled out any that have centerboard systems for this reason.

[Orion Jim]

Alden Designs - Hart Nautical Collection, MIT Museum - Designers of Fine Yachts

They allow in-person access to the plan archive. Contact them. They have the Alden 44 and the Alden 44 MK II plans in their archives. The builder is out of business.

[DougR]

The designer of the Alden 44 was Mr. Niels Helleberg. He is a naval architect and was chief designer of Alden Yachts.

Contact info seems to be:
Niels Helleberg Yacht Design
23 Glendale St
Salem, MA
617-227-7997

I seem to recall that he retired and closed up shop a few years ago, but perhaps he still can be contacted. Good luck.

[coopec43]

Originally Posted by BDZ123

Hello all! I’m currently looking at an Alden 44 as a live aboard for our family for the next couple of years. I really love these boats, but the one we’re looking at has had the center board removed, presumably “permanently”, including (obviously) filling the hole in the hull/keel for the lifting mechanism, etc. My question is:
How well do they sail without the center board? Is not having it prohibitive, or does it simply make pointing less efficient?
we’re ok with a slightly decrease in performance, but don’t want to end up with a boat that doesn’t point at all and can’t hold a line.
Thanks so much for any thoughts!!!

Maybe it would be better to start a new thread (which is specific to your problems) rather than add to threads that are 3 years and 6 years old (which are not really relevant anyway).

I'd be alarmed if someone removed a center board. Presumably the naval architect put it there for a reason!

[Jammer]

Originally Posted by coopec43

Presumably the naval architect put it there for a reason!

Presumably the reason was that the design brief given to the NA called for a centerboard because, at the time, that was a popular configuration that sold well.

[coopec43]

Originally Posted by Jammer

Presumably the reason was that the design brief given to the NA called for a centerboard because, at the time, that was a popular configuration that sold well.

"According to Philip, the centerboard model can sail just about anywhere. “Obviously a full keel would be better, but then you can’t get into shallow water, so the ability to go anywhere is a tradeoff,” he said."

Why not go the whole hog and do away with the keel completely?

https://sailingmagazine.net/article-1504-alden-44.html

[rapignataro]

Originally Posted by coopec43

Maybe it would be better to start a new thread (which is specific to your problems) rather than add to threads that are 3 years and 6 years old (which are not really relevant anyway).

I'd be alarmed if someone removed a center board. Presumably the naval architect put it there for a reason!

You can sail without a centerboard, but you will loose some performance against the wind. It is a shame.
Alden 44 is a great sailboat. I keep mine with the centerboard runing.

[BDZ123]

Originally Posted by rapignataro

You can sail without a centerboard, but you will loose some performance against the wind. It is a shame.
Alden 44 is a great sailboat. I keep mine with the centerboard runing.

How much of a loss against the wind are we talking? Is it losing a couple of degrees of pointing ability or significant leeway? I would prefer the boat have the centerboard, but it may not be a deal breaker if the difference is more "fine tuning" of performance, rather than an essential piece of equipment.

[BigKirkManitoba]

Hi I’m looking at an Alden 44. Can we chat!?

[nuku34]

Ok boys and girls, let's cut to the chase here and answer the Op's question shall we?


Disclaimer: I actually own an Alden 46. This yacht and the Alden 44 and the Alden 52 all have the same centerboard design and mechanism, and all designed by Neils Helberg in the 80's. I have the original blueprint of the 46 and 52 centerboard detail on my computer as a pdf file. The 44 is very similar. Happy to send that file to the OP.



On my 46, the solid fibreglass hull has a moulded-in "stub" keel about 0.4m deep. Bolted to this is a long lead fin keel. All the keel weight is in that lead. The board is a hollow foil-shaped fibreglass unit that, when up, is fully retracted into the long slot in the bottom of the lead keel. The board actually has positive buoyancy. My yacht draws 1.75 with board up and 3.2m with board down.


The board is controlled by a double acting hydraulic ram that is part of a Navtec System 5 hydraulic system with 3 functions: backstay, vang and centreboard. A manual pump provides pressure up to 3,000 psi. I think all the 3 Aldens had this same Navtec System 5 since they were all 80's designs by Neils Helsberg.


The double acting hydraulic ram has 2 oil lines; one pushes the ram's rod in and the other out. Each line has a pressure relief valve close to the ram. If the "down" valve is adjusted properly and you hit the bottom going forward with the board down, the valve will pop open and allow the board to swing back and up. If you are going backwards, you will break the board! If the ram somehow becomes disconnected from the board (that's the Op's problem), then the board, if down, should just float up into the slot. the pressure relief valve in the "up" side line is there so you won't beak things if you keep pumping after the board is fully up. There is no visual indication of board's position other than lifting a floor board and looking at the position in or out of the ram's push rod.



The board has 3 functions: 1) when beating it provides "lift" to windward and 2) reduces leeway. It is un-weighted so it doesn't affect the stiffness of the yacht up or down. On a reach, you can play with the board up and down to adjust the helm balance. We generally don't do this because we attain helm balance using the sail trim, and the board does add drag when down. However, on the wind we use it almost all the time.


The board is not an after thought! It is an integral part of the yacht's design and it would be very very stupid to remove it. Yes, it does add complexity, but do you really want to sail around drawing 3.2m (10 ft) all the time or only 1.75m? With this design, you get relatively shallow draft for the size of yacht plus the added performance of a deep fin keel.


I personally like a yacht that goes well into the wind. I've done a heap of racing so I know what good windward performance is like. In my 32 years of cruising and 70,000 off-shore miles, there were many times when windward ability (or lack of) was a safety factor. 4 of my 5 yachts didn't have great windward performance and there were times when I had to use the engine to get to a safe place located dead to windward. Luckily I had reliable engines. My Alden 46 doesn't have that problem unless there's under 6kts of breeze.



Now to the details and what might be wrong with the Op's board. The keel cross section is quite complex. There is the slot in the bottom where the board sits, and there is another slot in the top which is offset from the slot in the bottom. The bottom of the top slot ends up about 0.3m lower than where the board's pivot pin is located in the bottom slot. The pin goes through the vertical "wall" between the slots and has a simple stuffing box type seal to keep the water out of the dry slot. In the upper dry slot, the pin has a short "arm" to which the ram's rod attaches. When the rod moves in and out it causes the pin to turn. in the lower wet slot, the pin goes through the board. The pin has a big keyway and key that engages with the key-hole shaped hole in the board. There are bronze bushings that the pin turn on.



Now, the Op says the ram is moving but the board isn't. It has to be 1) the short "arm" on the pin is slipping on the pin (it too has a keyway and key in the pin that engages in the arm's hole), or 2) the pin is slipping where it goes through the board itself.



If its the arm slipping, then it might be possible to fix it by removing floorboards to expose the upper slot and attempting to re-fix the arm to the pin. On my yacht, that pin and arm is about 0.6m down in a narrow slot. The top of the slot is about 0.3m below the floorboards. You can't get your body down in that slot, its just too narrow. It would be a real bitch to reach down with tools to 0.9m while lying on your stomach on the floorboards, but might be possible.


If the arm is turning the pin and the board isn't moving, then you'll need to haul out and get dirty. You will need to block the hull up high enough to let the board hanging down maybe 0.5m (or dig a trench in the ground before hand). There are openings in the lead keel on both sides that allow access to the big pin. You will need to find these openings since they will be faired into the keel and hidden by filler. The pin can then be withdrawn and you can see what the problem is. Sheared key, or the hole in the board is buggered up. It will not be fun.


A member with an Alden 44 replied to a thread of mine describing his experiences.

that will be very useful to the OP:
https://www.cruisersforum.com/forums...ml#post3797571