Swing keel
- Thread starter davedawe
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My Mariner is a '70 2+2 built by O'Day. The swing keel is steel and weighs 150+
Pounds the weight keeps it down - there is no locking mechanism.
Not sure about the newer Stuart Mariner's with fiberglass CB.
Dan
Well, first thing is that the MARINER does not have a swing-keel, so the question is a bit hard to answer.
However, the MARINER's 165# cast-iron centerboard (there is also 200# of lead ballast in 2 pieces glassed into the bilge) did have a lock-down pin from what I've heard, however.... I don't think too many owners use the pin if they even still have it. If I were sailing in potentially shallow water, I wouldn't use it if I had one. There definitely was a pin to hold the CB up all the way, but I must admit, the owners manual that I have does not mention the pin to lock the CB down:
"Centerboard
The centerboard winch is a reel-type winch which makes it possible to raise or lower the 165 lb. centerboard. WE RECOMMEND YOU KEEP AT LEAST A TURN AND A HALF OF WIRE ON THE DRUM AT ALL TIMES, which will prevent the wire from pulling out of the drum (See Fig. 5).
NEVER lower the centerboard all the way, as it can hit the front of the centerboard trunk and could fracture the fiberglass. Be sure to raise the centerboard all the way and insert the centerboard pin through hole in the centerboard trunk so it will pass through centerboard, which will take the strain off the cable while trailing or when you are through sailing.
The position of the c/b can be changed by adjusting the c/b pendant – while sailing the amount of helm (pressure) on the tiller can be changed by c/b position; i.e., raise to decrease; lower it increase. It is not recommended to raise more than half way as this would create too much sideslip.
Should the centerboard bolt leak, it can be tightened. If leaking still persists, seal the bolt with a substance like silicone sealant."
There is a manual available in PDF format on this web site, just click on the "Boat Info" tab at the top, then on "O'Day Boat info", then on "MARINER", then on "O'Day Mariner Owner Modifications", the manual is listed as "Mariner operating tips". This will be the 1973-78 version of the manual, but most of it will apply to any O'DAY Mariner.
In answer to the specs for the Stuart Mariner, those boats have a 70# fiberglass CB with 250# of lead in the bilge.
However, the MARINER's 165# cast-iron centerboard (there is also 200# of lead ballast in 2 pieces glassed into the bilge) did have a lock-down pin from what I've heard, however.... I don't think too many owners use the pin if they even still have it. If I were sailing in potentially shallow water, I wouldn't use it if I had one. There definitely was a pin to hold the CB up all the way, but I must admit, the owners manual that I have does not mention the pin to lock the CB down:
"Centerboard
The centerboard winch is a reel-type winch which makes it possible to raise or lower the 165 lb. centerboard. WE RECOMMEND YOU KEEP AT LEAST A TURN AND A HALF OF WIRE ON THE DRUM AT ALL TIMES, which will prevent the wire from pulling out of the drum (See Fig. 5).
NEVER lower the centerboard all the way, as it can hit the front of the centerboard trunk and could fracture the fiberglass. Be sure to raise the centerboard all the way and insert the centerboard pin through hole in the centerboard trunk so it will pass through centerboard, which will take the strain off the cable while trailing or when you are through sailing.
The position of the c/b can be changed by adjusting the c/b pendant – while sailing the amount of helm (pressure) on the tiller can be changed by c/b position; i.e., raise to decrease; lower it increase. It is not recommended to raise more than half way as this would create too much sideslip.
Should the centerboard bolt leak, it can be tightened. If leaking still persists, seal the bolt with a substance like silicone sealant."
There is a manual available in PDF format on this web site, just click on the "Boat Info" tab at the top, then on "O'Day Boat info", then on "MARINER", then on "O'Day Mariner Owner Modifications", the manual is listed as "Mariner operating tips". This will be the 1973-78 version of the manual, but most of it will apply to any O'DAY Mariner.
In answer to the specs for the Stuart Mariner, those boats have a 70# fiberglass CB with 250# of lead in the bilge.
You don't want the centerboard locked down. Centerboards are great because if you happen to sail into shallow water you will hear that board dragging the ground and you'll know right away that you need to get out of there and get back into deep water. I can't imagine what would happen if a guy was sailing with a locked down centerboard and his board hit a large underwater rock.
The guy's head would probably be flattened out against the cuddy cabin bulkhead. It's that sudden stop that always hurts the most.
The guy's head would probably be flattened out against the cuddy cabin bulkhead. It's that sudden stop that always hurts the most.
Joe, from experience with our CAL 21 (on which, being a retractable keel boat, we did lock the keel down) the boat tends to come to a screeching halt, there is a LOUD BANG!!, the locking pin/bolt will bend and the Keel or Centerboard trunk around the pin/bolt will be damaged.
On a DS II the boat will stop with a bang, the line holding the CB down suddenly becomes VERY tight, and perhaps a chip or chunk of the CB will break off. Thankfully, I've only found a couple of rocks...and more luckily... had that hold down line loose at the time.
One of those rock encounters was enough to actually cause the CB to "rebound" right up into the trunk..... Guess I was a bit "off" on my memory of just where that rock is? OOPS!
I have run aground on sand with the CB tied down...... thankfully sand "gives" a bit and I could untie the line before damage happened. I stil ltend to keep the CB tied down while sailing, unless I sail where I know there are some rocks or even intend to cross a shallow sandbar.
The reason for the hold-down pin on the MARINER (when/if fitted) was to keep the CB down when racing in deep water. This was to keep the CB down if the boat was laid on her side in a gust, supposedly... the MARINER would meet M.O.R.C. self-righting requirements with the CB locked down.
The pin was not intended to be used in shallow water, and my feeling is that under normal sailing conditions, the 165# weight of the CB should hold it down OK. The 200# of lead in the bilge combined with the weight of the CB, should keep the boat upright under normal conditions, especially if the boat is sailed like the centerboard boat she is. Actually, even without a pin locking the CB down....... with a 165# cast-iron CB, I think the boat will still come to a pretty fast stop if a rock pops up less than 4'11" below the surface.........but hopefully with little damage over than a bit of lost paint on the edge of the CB.
I may be wrong about there ever being a pin to hold the CB down...... but I still think I heard about one somewhere, however....... I really can't see the need for it and just found the following picture.......which tends to show that the CB should stay down in a "knockdown" even without a pin.
On a DS II the boat will stop with a bang, the line holding the CB down suddenly becomes VERY tight, and perhaps a chip or chunk of the CB will break off. Thankfully, I've only found a couple of rocks...and more luckily... had that hold down line loose at the time.
One of those rock encounters was enough to actually cause the CB to "rebound" right up into the trunk..... Guess I was a bit "off" on my memory of just where that rock is? OOPS!
I have run aground on sand with the CB tied down...... thankfully sand "gives" a bit and I could untie the line before damage happened. I stil ltend to keep the CB tied down while sailing, unless I sail where I know there are some rocks or even intend to cross a shallow sandbar.
The reason for the hold-down pin on the MARINER (when/if fitted) was to keep the CB down when racing in deep water. This was to keep the CB down if the boat was laid on her side in a gust, supposedly... the MARINER would meet M.O.R.C. self-righting requirements with the CB locked down.
The pin was not intended to be used in shallow water, and my feeling is that under normal sailing conditions, the 165# weight of the CB should hold it down OK. The 200# of lead in the bilge combined with the weight of the CB, should keep the boat upright under normal conditions, especially if the boat is sailed like the centerboard boat she is. Actually, even without a pin locking the CB down....... with a 165# cast-iron CB, I think the boat will still come to a pretty fast stop if a rock pops up less than 4'11" below the surface.........but hopefully with little damage over than a bit of lost paint on the edge of the CB.
I may be wrong about there ever being a pin to hold the CB down...... but I still think I heard about one somewhere, however....... I really can't see the need for it and just found the following picture.......which tends to show that the CB should stay down in a "knockdown" even without a pin.
Attachments
I think for ordinary day sailing there shouldn't be a need to lock the centerboard in the down position if the boat had that provision. You run the risk of breaking something on your boat if your centerboard were to hit a large submersible object. Personally, if I had a locking mechanism on my centerboard, I'd never use it. It's bad enough that I need to lock my tip up rudder blade down. I'd like to install a flip up cleat that would let it pop up if the rudder hits something. They have such a cleat but I don't think that it would work upside down on the under side of my tiller.
I stand corrected! They do make an auto release jam cleat that works upside down. :dance: Hmmm.
http://www.duckworksbbs.com/hardware/cleats/sd002570/index.htm
http://www.duckworksbbs.com/hardware/cleats/sd002570/index.htm
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