When can I disconnect my baby stay ?

[Boo2]

Hi,

Sunrunner (UFO 34) has a baby stay which runs from the deck about 6 feet in front of the mast to the mast at the height of the lower spreaders. It is connected to the deck with an over-centre arrangement so presumeably it is intended to not be in use some of the time.

Can anyone tell me when it should be connected and when it should not ?

Thanks,

Boo2

 

[lenseman]

When you say 'Baby-Stay, does it run from the port and starboard deck (chain-plates) to the hounds below the lower spreaders or does it run directly for'ward towards the pulpit and prow?

You might be referring to a temporary fore-stay used for a storm jib or stay-sail?

 

[VicS]

Does it have the baby stay in place of forward lower shrouds?

 

[mixmaster]

Ideally always have it on. We disconnect ours if running with a spinnaker and expect to jibe or when tacking in light winds to help clear the genoa. Otherwise just leave it in place.

 

[Jcorstorphine]

Word of Caution

Hi,

Sunrunner (UFO 34) has a baby stay which runs from the deck about 6 feet in front of the mast to the mast at the height of the lower spreaders. It is connected to the deck with an over-centre arrangement so presumeably it is intended to not be in use some of the time.

Can anyone tell me when it should be connected and when it should not ?

Thanks,

Boo2

I had a baby stay on a little 4 ton sloop which was a real pain. When we came about, the jib sheets got caught in it every time so took it off to see what would happen. The mast bent alarmingly back from the point where the baby stay was anchored to the mast (at the cross trees) Must have bowed about 6 inches so it was put back on.

Might be ok to take it off on a run as its absence could make handling spinnaker pole easier but if beating to windward or a reach, might be better to leave on.

PS There is a further variant in rigs which I forgot to mention. If you have spreaders which are racked back and the cap shrouds are taken to a point approx 18” behind the mast, then you may find that the mast does not bend when you take off the baby stay as the raked spreaders will take some of the strain.

Think this is one for the racing fraternity.

 

[William_H]

Baby stay

AKA the inner forestay. This is common on mast head rigs. The top of the mast is located by the forestay the backstay and the 2 cap shrouds. The middle of the mast is located by the inner forestay and the 2 intermediate sidestays which will be attached to chain plates aft of abeam the mast.
This dimension aft of abeam the mast provides a pull aft of the middle of the mast which is counteracted by the baby stay and the dimension that its attachment is forward of the mast.
Assuming that your mast rigging is similar to that above then the location of the middle of the mast is vital to mast integrity. It can crumple middle back if loaded heavily. This load will typically come from load on the forestay via a tight jib or load from the cap shrouds from both jib and main.
Obviously with light loads ie light wind the mast depth fore and aft will provide stiffness in the middle fore and aft direction however this is limited. If you do disconnect the baby forestay then the static tension of the intermediate sidestays will tend to pull the middle of the mast aft precipitating any buckling failure.

So for consistency and safety I would suggest you always leave it connected.
However for better performance in strong winds it is common to apply more tension to the baby forestay. This is often done via tackle on the bottom of the baby stay. This added tension in conjunction with added backstay tension will tend to bend the mast middle forward. This has the effect of taking out some of the fullness of the mainsail. Which is better for strong winds. Further the added backstay tension tensions the forestay so takes out some of the forestay sag which also takes out some of the fullness (camber) of the jib.
So depending on the dimensions of the high field lever it may be appropriate to release the lever for light winds and pull it on for strong winds. The middle of the mast might move forward about 3 inches with tension on. This might be typical if the high field lever extends the baby forestay around 2 or 3 inches.

On the other hand the high field lever may be fitted to make mast lowering easier. This especially so if opening the lever makes inner forestay quite slack so easy to disconnect completely. If the baby stay is extended by more than 3 inches I would suggest this will be too slack even for light winds if opened but still connected.

So the inner forestay (baby forestay) does an important job. It makes a typical mast head rig very robust. As said it may be replaced by 2 inner forestays running to the gunwhale where often the jib can move across inside the inner forestays. You might want to consider this variation. Otherwidse people put up with the difficulty of moving the jib across. Often they fit plastic pipe on the inner forestay to help jib slide across it.
A fractional rig as said will have spreaders and cap and inner sidestays a long way from abeam the mast. This means you don't need an inner forestay to support the middle of the mast but does cause chafe on mainsail when you are running. This kind of rig is more modern but not as simply robust. I lost a mast on this type of rig because a spreader base failed allowing it to swing forward. The middle of a mast does need support when there is pressure on it.
So leave inner forestay in place. god luck olewill

 

[DanTribe]

william.h
That's a very full and helpful explanation, you obviously know what you'r talking about.
Does the fact of a keel stepped mast supported a deck level have any effect?.

 

[sailorman]

AKA the inner forestay. This is common on mast head rigs. The top of the mast is located by the forestay the backstay and the 2 cap shrouds. The middle of the mast is located by the inner forestay and the 2 intermediate sidestays which will be attached to chain plates aft of abeam the mast.
This dimension aft of abeam the mast provides a pull aft of the middle of the mast which is counteracted by the baby stay and the dimension that its attachment is forward of the mast.
Assuming that your mast rigging is similar to that above then the location of the middle of the mast is vital to mast integrity. It can crumple middle back if loaded heavily. This load will typically come from load on the forestay via a tight jib or load from the cap shrouds from both jib and main.
Obviously with light loads ie light wind the mast depth fore and aft will provide stiffness in the middle fore and aft direction however this is limited. If you do disconnect the baby forestay then the static tension of the intermediate sidestays will tend to pull the middle of the mast aft precipitating any buckling failure.

So for consistency and safety I would suggest you always leave it connected.
However for better performance in strong winds it is common to apply more tension to the baby forestay. This is often done via tackle on the bottom of the baby stay. This added tension in conjunction with added backstay tension will tend to bend the mast middle forward. This has the effect of taking out some of the fullness of the mainsail. Which is better for strong winds. Further the added backstay tension tensions the forestay so takes out some of the forestay sag which also takes out some of the fullness (camber) of the jib.
So depending on the dimensions of the high field lever it may be appropriate to release the lever for light winds and pull it on for strong winds. The middle of the mast might move forward about 3 inches with tension on. This might be typical if the high field lever extends the baby forestay around 2 or 3 inches.

On the other hand the high field lever may be fitted to make mast lowering easier. This especially so if opening the lever makes inner forestay quite slack so easy to disconnect completely. If the baby stay is extended by more than 3 inches I would suggest this will be too slack even for light winds if opened but still connected.

So the inner forestay (baby forestay) does an important job. It makes a typical mast head rig very robust. As said it may be replaced by 2 inner forestays running to the gunwhale where often the jib can move across inside the inner forestays. You might want to consider this variation. Otherwidse people put up with the difficulty of moving the jib across. Often they fit plastic pipe on the inner forestay to help jib slide across it.
A fractional rig as said will have spreaders and cap and inner sidestays a long way from abeam the mast. This means you don't need an inner forestay to support the middle of the mast but does cause chafe on mainsail when you are running. This kind of rig is more modern but not as simply robust. I lost a mast on this type of rig because a spreader base failed allowing it to swing forward. The middle of a mast does need support when there is pressure on it.
So leave inner forestay in place. god luck olewill

i have the biogger sister to the UFO 34 with a similar rig.
the baby stay has a wheel tensioner & quick release shackle at the bottom.
it is removed when gybing the pole. the mast as the 34 is keel stepped.
the cap & inters go down to chainplates in line with the mast base at deck level so no tri-angulation

 

[chewi]

i have the biogger sister to the UFO 34 with a similar rig.
the baby stay has a wheel tensioner & quick release shackle at the bottom.
it is removed when gybing the pole. the mast as the 34 is keel stepped.
the cap & inters go down to chainplates in line with the mast base at deck level so no tri-angulation

In which case william H's detailed reply for a backswept aft lowers rig does not apply, does it?

What then stabilises the mast fore and aft if it's not triangulated by the lowers? does it have running backstays?

 

[reeac]

william.h
That's a very full and helpful explanation, you obviously know what you'r talking about.
Does the fact of a keel stepped mast supported a deck level have any effect?.

I can't see that keel stepping helps in this respect. At best the keel stepped mast will be perfectly located at deck level making it equivalent to a deck stepped mast but if there's any play at deck level [albeit kept watertight by some boot arrangement] then a given mast will more flexible and be more dependent on intermediate stays.

 

[sailorman]

In which case william H's detailed reply for a backswept aft lowers rig does not apply, does it?

What then stabilises the mast fore and aft if it's not triangulated by the lowers? does it have running backstays?

we do have "Check stays" but only needed in lumpy conditions to stop the mast from "panting"

 

[sailorman]

I can't see that keel stepping helps in this respect. At best the keel stepped mast will be perfectly located at deck level making it equivalent to a deck stepped mast but if there's any play at deck level [albeit kept watertight by some boot arrangement] then a given mast will more flexible and be more dependent on intermediate stays.

all keel stepped masts should be firmly wedged @ deck level

 

[Boo2]

When you say 'Baby-Stay, does it run from the port and starboard deck (chain-plates) to the hounds below the lower spreaders or does it run directly for'ward towards the pulpit and prow?

Directly forwards to a point about 6 foot or so in front of the mast.

You might be referring to a temporary fore-stay used for a storm jib or stay-sail?

No, it's way too far back to be any use for that.

Boo2

 

[Boo2]

Does it have the baby stay in place of forward lower shrouds?

I don't really know how you define forward lower shrouds ? There are only 2 shrouds meeting the deck on either side, both are abaft the mast - see pic below.

Boo2

 

[Tranona]

Think it has really been covered already, but a masthead rig needs support against the pull of the forestay - particularly on foretriangle dominated rigs like yours. On many cruising boats this is achieved by having two lower shrouds each side, one forward and one aft of the mast. This supports the centre of the mast. The downside of this is that the forward shroud can limit sheeting of the genoa, so, as in your rig, the alternative is to use a single babystay. In your case it is detachable, because the downside is that it compromises spinnaker handling, so is made removeable as the need for mast support is less when running under spinnaker than beating. Bit inconvenient, but OK when you have a load of gorillas on board to handle the gear.

For cruising and shorthanded sailing best to leave it on and deal with the inconvenience when tacking. Probably leave it on if using a spinnaker shorthanded as you probably want to avoid regular gybing, where it can be a nuisance.

BTW the subject of babystays is discussed in this month's PBO in an article on the rigs on Squib/Europa - smaller boats, but same issues.

 

[VicS]

Quote:
Originally Posted by VicS
Does it have the baby stay in place of forward lower shrouds?
I don't really know how you define forward lower shrouds ? There are only 2 shrouds meeting the deck on either side, both are abaft the mast - see pic below.

Boo2

As I suspected from the (poor) photos I had found of the boat. ... hence the question.

Anyway Tranona has answered and explained all I think.

 

[Boo2]

AKA the inner forestay....

..snip comprehensive reply.

Thanks for that. I'm not at the boat right now but I think my lever is intended to permit the mast to be lowered as you suggest.

I have not found tacking particularly difficult with the babystay in place (there are plastic pipes around the shrouds and babystay) so I will take your advice and leave it fitted at all times.

Boo2

 

[Boo2]

...snip
BTW the subject of babystays is discussed in this month's PBO in an article on the rigs on Squib/Europa - smaller boats, but same issues.

Interesting, I'll have a look next time in Smiffs.

Thanks to all for the replies, the upshot seems to be leave it connected at all times so I'll do that and see how I get on.

Boo2

 

[sailorman]

..snip comprehensive reply.

Thanks for that. I'm not at the boat right now but I think my lever is intended to permit the mast to be lowered as you suggest.

I have not found tacking particularly difficult with the babystay in place (there are plastic pipes around the shrouds and babystay) so I will take your advice and leave it fitted at all times.

Boo2

Thanks for that. I'm not at the boat right now but I think my lever is intended to permit the mast to be lowered as you suggest.


I very much doubt that is its primary function

 

[BAtoo]

BTW the subject of babystays is discussed in this month's PBO in an article on the rigs on Squib/Europa - smaller boats, but same issues

Not seen the article neither Squibs or Europas have baby stays....