bulbs gone

[Powersalt]

The bulb has gone in the masthead light of our first 21.7 . Do you think , given that the rig is very light and the boat pretty tender that someone could go up the mast to fix it or should we lower the mast and be prudent despite the extra work.

Any one any experience of this?

 

[benlui]

I once saw a guy with a similar size boat tie to a high pier on a very low tide, take the main halyard ashore and pull the mast towards him where he could reach the mast head light and preform the required duty!
I watched in amazement as he successfully completed the task with little bother.

Fascinating, and obviously possible for smaller boats............

Other than that, its a good excuse to drop the mast and check the rigging too......
If in doubt, i wouldnt send anybody up there.

 

[prv]

It's not immediately intuitive, but someone hanging on a halyard exerts the same force on the boat whether they're at the masthead or six inches off the deck. So if you get in your bosun's chair and swing about a bit, and it doesn't feel like the boat's going to turn turtle, then in theory you should be OK.

Personally I'd probably get the mast down anyway though

Pete

 

[vyv_cox]

Another alternative that I've seen used successfully is similar to benlui's but using the mast of a bigger boat. Take your halyard across to a friend's mast and pull yours towards it, using a winch as necessary.

 

[DJE]

The bulb has gone in the masthead light of our first 21.7 . Do you think , given that the rig is very light and the boat pretty tender that someone could go up the mast to fix it or should we lower the mast and be prudent despite the extra work.

Any one any experience of this?

Similar thread here.
A friend with a Beneteau 211 lifting keel just hauls her over using the main halyard with the keel raised.

 

[Daedelus]

It's not immediately intuitive, but someone hanging on a halyard exerts the same force on the boat whether they're at the masthead or six inches off the deck. So if you get in your bosun's chair and swing about a bit, and it doesn't feel like the boat's going to turn turtle, then in theory you should be OK.

Pete

This may be true while the mast is near vertical but if you start to lean the boat over a little then the length of the mast acts as a lever and the force to pull the boat over will be multiplied by the moment (lever length x mass). Try the experiment with a stick and a small weight if you don't believe it. (If you do want to try with the boat, can you advise Snooks so he take pictures for a future YM)

 

[Signed Out]

This may be true while the mast is near vertical but if you start to lean the boat over a little then the length of the mast acts as a lever and the force to pull the boat over will be multiplied by the moment (lever length x mass). Try the experiment with a stick and a small weight if you don't believe it. (If you do want to try with the boat, can you advise Snooks so he take pictures for a future YM)

But again still same if on a line from the top- the mast will still be there as a lever, no longer, no shorter. And surely, in fact, if holding mast on way up, the lever IS shorter.

I remember from stability classes that the dangerous moment when lifting with a ship's crane, is the moment the load leaves the deck as the GM shoots up.

Kind of like an upside down version of Standing up on the pegs of a motorbike on slow going to add stability- as long as you don't brace the bike, the lever is at your feet, not your bum.

 

[Allan]

The bulb has gone in the masthead light of our first 21.7 . Do you think , given that the rig is very light and the boat pretty tender that someone could go up the mast to fix it or should we lower the mast and be prudent despite the extra work.

Any one any experience of this?

My boat has mast steps and a number club members have used it to get to the top of their masts. It might be worth havine a look around where you keep your boat to see it there are any with steps.
I used to have an Etap22i which, being a trailor sailor, I could get the mast down single handed.
Allan

 

[prv]

It's not immediately intuitive, but someone hanging on a halyard exerts the same force on the boat whether they're at the masthead or six inches off the deck.

This may be true while the mast is near vertical but if you start to lean the boat over a little then the length of the mast acts as a lever and the force to pull the boat over will be multiplied by the moment (lever length x mass).

Would you like to think about that again? Try drawing a diagram, with an arrow representing the downward force on the masthead. In fact try two, one with a 2-foot halyard and one with a 20-foot halyard, and then try to justify how you can possibly draw different arrows just because of the length of the halyard.

(I am neglecting the effect of landing in the water at a certain angle of heel in the long-halyard case. It doesn't apply to the practical technique because if it feels like there is any chance at all of it happening, you don't go up the mast - that is the entire purpose of the experiment.)

Pete

 

[Quandary]

If a rig is not stable enough to carry the weight of a person then there is no way you should go out in it above a F2. You might swing about a bit particularly if the crew on deck start walking about but you will never go over. We used to try to winch small boats over by taking a halyard acros the river to scrub the bottom when winter racing, you could get a Puppeter 22 to about 30 degrees off the vertical before it pulled the tree out.

 

[Signed Out]

If a rig is not stable enough to carry the weight of a person then there is no way you should go out in it above a F2. You might swing about a bit particularly if the crew on deck start walking about but you will never go over. We used to try to winch small boats over by taking a halyard acros the river to scrub the bottom when winter racing, you could get a Puppeter 22 to about 30 degrees off the vertical before it pulled the tree out.

Musta been a bloomin' flimsy tree! Am guessing the keel was down, or the warps were tight on the far side!

 

[wiggy]

My brother at 15 stone went up the mast of his Etap22i many years ago, job done, he came down safely then realised the keel had been raised the whole time-DOH! He has carried on in the same chaotic manor ever since.

 

[Signed Out]

My brother at 15 stone went up the mast of his Etap22i many years ago, job done, he came down safely then realised the keel had been raised the whole time-DOH! He has carried on in the same chaotic manor ever since.

They do have a whopping great bulb on the keel though, and if I am not mistaken, even those don't go right up to hull. But still, I'd have rather the keel down if I did that!

 

[Allan]

They do have a whopping great bulb on the keel though, and if I am not mistaken, even those don't go right up to hull. But still, I'd have rather the keel down if I did that!

Sorry to drift the thread but I think the OP has plenty to think about.
You are correct about the keel of an Etap22i, nice big bulb that stays out of the hull when up (needs 400mm of water to float with it up).
When trying to put people at ease about yachts leaning (mostly wives of friends), I explain that if you were to suspend the keel on a pivot you would have no problem pushing it 6". If it were then lifted to 30 degrees you could not move it. My point being that the keel does not do much when the boat is upright but the more the boat leans over, the more the keel is working to right it. Hence it will lean but should not fall over.
When climbing the mast, the keel will do little to stop it rocking and, as long as you stay out of the water, by the time the boat is far enough over for the keel to work, the climber could be far enough over to out weigh it. The main reason for posting this is to see if I am wrong, so feel free to pull it apart.
Allan