Changing the angle of the babystay

Kelpie

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Bit of a hypothetical question, for now, but curious to see if I'm missing anything.
One of the downsides of a babystay is that it makes your usable foredeck area much smaller. For my intended cruising plans, I want to have a hard tender (or RIB) mounted on davits for day to day storage, and put on the foredeck for longer (multi day) passages.

What I am considering is making an extension for the babystay, so that it can be anchored further up the foredeck, likely at the bow chainplate itself unless another location seemed easier. This would be a reversible arrangement- the original babystay chainplate would remain in place, and the extension piece could be removed to revert the rig to the original plan.
The obvious downside of this arrangement is that tacking the headsail becomes much harder, and you would probably need to furl it and unfurl it each time. But as I said, this arrangement would be for use on long multi-day passages where you would a) hopefully not be beating anyway; and b) be in open water where you might only change tack every few days.

What I'm not too sure about is the effect on the rig. Obviously you would need the babystay tang to have sufficient articulation to cope with the change in angle, but the way that the mast is held in column might be slightly different, and the loadings on the babystay attachment on the mast would be somewhat more in tension than in shear. But I might be overthinking things!

Any thoughts?
 

bbg

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Bit of a hypothetical question, for now, but curious to see if I'm missing anything.
One of the downsides of a babystay is that it makes your usable foredeck area much smaller. For my intended cruising plans, I want to have a hard tender (or RIB) mounted on davits for day to day storage, and put on the foredeck for longer (multi day) passages.

What I am considering is making an extension for the babystay, so that it can be anchored further up the foredeck, likely at the bow chainplate itself unless another location seemed easier. This would be a reversible arrangement- the original babystay chainplate would remain in place, and the extension piece could be removed to revert the rig to the original plan.
The obvious downside of this arrangement is that tacking the headsail becomes much harder, and you would probably need to furl it and unfurl it each time. But as I said, this arrangement would be for use on long multi-day passages where you would a) hopefully not be beating anyway; and b) be in open water where you might only change tack every few days.

What I'm not too sure about is the effect on the rig. Obviously you would need the babystay tang to have sufficient articulation to cope with the change in angle, but the way that the mast is held in column might be slightly different, and the loadings on the babystay attachment on the mast would be somewhat more in tension than in shear. But I might be overthinking things!

Any thoughts?

My thoughts would be that for multi day passages you might deflate the RIB and store it elsewhere.
 

NormanS

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I don't think that moving the stay forward would make a huge difference at its attachment up the mast. Is it a permanent part of the support system for the mast? The reason for asking is that I have something similar, but it is only used for rigging a storm jib, so while it has a properly designed and adequate attachment point, in practice it spends its life attached much closer to the mast, and out of the way.
 

geem

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Bit of a hypothetical question, for now, but curious to see if I'm missing anything.
One of the downsides of a babystay is that it makes your usable foredeck area much smaller. For my intended cruising plans, I want to have a hard tender (or RIB) mounted on davits for day to day storage, and put on the foredeck for longer (multi day) passages.

What I am considering is making an extension for the babystay, so that it can be anchored further up the foredeck, likely at the bow chainplate itself unless another location seemed easier. This would be a reversible arrangement- the original babystay chainplate would remain in place, and the extension piece could be removed to revert the rig to the original plan.
The obvious downside of this arrangement is that tacking the headsail becomes much harder, and you would probably need to furl it and unfurl it each time. But as I said, this arrangement would be for use on long multi-day passages where you would a) hopefully not be beating anyway; and b) be in open water where you might only change tack every few days.

What I'm not too sure about is the effect on the rig. Obviously you would need the babystay tang to have sufficient articulation to cope with the change in angle, but the way that the mast is held in column might be slightly different, and the loadings on the babystay attachment on the mast would be somewhat more in tension than in shear. But I might be overthinking things!

Any thoughts?
How much space do you have in front of the existing baby stay for a dinghy? Our hard nesting dinghy sits in front of the baby stay. Nested we only have a 7’ dinghy. Jointed its 12’5”. Do you really need to move the babystay. We dont have davits as we have a Duogen, a Windpilot and a boarding ladder on the transom. We tow the dinghy between islands as its drag isnt even noticeable (a big advantage of a light long hard dinghy) compared to our previous rib that was like towing a bus with a flat tyre!
 

Kelpie

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My thoughts would be that for multi day passages you might deflate the RIB and store it elsewhere.

Even deflated, the hull is going to be quite a big lump to store, and the length is going to be almost the same, minus whatever the diameter of the bow tube.
 

BurnitBlue

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a baby stay solution used by some moody owners (described on the Moody Owners association website) is to add another sturdy mast tang a few feet higher then the original mast attachment than move the deck chain-plate (eye) to the anchor windlass well. This makes the new baby stay parallel with the forestay and can be used for a inner staysail it is good with a reefed main for windy conditions. Also space for a dinghy without fouling the anchor arrangements, It also solves the baby-stay deck lifting problem.
 

Kelpie

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How much space do you have in front of the existing baby stay for a dinghy? Our hard nesting dinghy sits in front of the baby stay. Nested we only have a 7’ dinghy. Jointed its 12’5”. Do you really need to move the babystay. We dont have davits as we have a Duogen, a Windpilot and a boarding ladder on the transom. We tow the dinghy between islands as its drag isnt even noticeable (a big advantage of a light long hard dinghy) compared to our previous rib that was like towing a bus with a flat tyre!

Haven't quite finalised purchase of the boat yet, so don't have that measurement to hand. It will all depend on the dinghy we choose, but that's a bit chicken and egg since deck space is obviously one consideration.
 

sarabande

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I move mine sideways so that it fastens to the inner shroud attachment point with a cord.. (Genoa sheets run outside the shrouds.)
 

Kelpie

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The babystay on this boat is definitely a permanent part of the rig. There are no forward lowers.
 

neil_s

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When built, my boat had a baby stay as part of the designed rig. A previous owner removed it and fitted instead two forward lower shrouds, complete with new chain plates. I wanted to play with a spinny and the forward lowers got in the way of the pole, so I reverted back to the baby stay. To my dismay, I found that the forward lowers provided much better support for the mast!
 

Kelpie

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It's a Moody 39- fairly short mast, deck stepped, masthead rig.
I could ask on the MOA forum but thought it might not really be a boat-specific question.
 

lpdsn

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It's a Moody 39- fairly short mast, deck stepped, masthead rig.
I could ask on the MOA forum but thought it might not really be a boat-specific question.

Could be worth asking them as someone else may have tried it.

It does sound like the baby stay is pretty important to your rig. With it being deck-stepped and masthead and nothing else supporting the middle section of the mast I'd be wary of the mast inverting in heavy weather or if you get caught out by a squall with the spinnaker up. So it would be very important that if you did move the baby stay that it was secure and strong enough to support the mast and wasn't going to be weakened by the change.
 
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Thinking of this another way, I disliked the way the dinghy was stowed on the coach roof in front of the mast, it was too big to go in the locker. I therefore bought a smaller dinghy without a solid transom that folds away into the cockpit locker. It is not inconvenient to inflate and use, deflate and stow. Maybe it's the RIB that needs to be looked at.
 

TLouth7

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From a structural point of view, the increased angle would allow the same forwards pull on the mast for a lower wire tension. So the new babystay ought to be able to do its job. The thing that changes is the angle of pull at the mast. You may have to fit a different end piece on your wire; that might preclude it moving back to the original position. Sounds like the job for some sort of swivel. Additionally you would want to be sure that the mast can withstand the new pull direction. Given that you are aiming for the same horizontal force I see no reason for this to be a problem.

Obviously when rigging this you would need to slacken off the aft lowers before removing the babystay. You would then need a tension gauge to get all 3 back to correct tension (checking mast bend as you go).

I make these comments purely as a layman, I am not a rigger or naval architect.
 

BurnitBlue

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Holy Smoke. Did the OP read my post above. The baby stay situation is a bad design error on moody boats and is discussed at length on MOA with some solutions.
 

NormanS

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Holy Smoke. Did the OP read my post above. The baby stay situation is a bad design error on moody boats and is discussed at length on MOA with some solutions.

You're in the wrong place if you expect people to pay attention to good advice.:D
 

Kelpie

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a baby stay solution used by some moody owners (described on the Moody Owners association website) is to add another sturdy mast tang a few feet higher then the original mast attachment than move the deck chain-plate (eye) to the anchor windlass well. This makes the new baby stay parallel with the forestay and can be used for a inner staysail it is good with a reefed main for windy conditions. Also space for a dinghy without fouling the anchor arrangements, It also solves the baby-stay deck lifting problem.

Sorry I totally missed this post- it must have appeared as I was typing my own reply.
If I understand correctly, this is a permanent alteration, not a movable one like I was proposing?
Sounds extremely useful, certainly for a boat destined primarily for long distance passage making rather than short tacking.
I've heard of a M41 being converted to forward lowers, which I think could be an excellent idea, but that is obviously a bigger project.
 

johnalison

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In that case, don't mess with it!

The baby stay on my old Sadler 29 started to part after some years' use, which gave me the impression that it was doing a lot of work. When you think about it, there must be a lot of potential movement at the mast centre as the boat pitches into each wave, so I would agree with those advising OP not to meddle, at least not without careful assessment.
 
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