Mast('s) Up or Down out of the water??

[swanny]

Mast(\'s) Up or Down out of the water??

Hi. I have kept my boat in Denmark for a couple of years and in the winter she has been in an unheated hall (and for those wondering.....now costing €1700 with crane out and in, jetwash, rented boat trolley, electricity in the shed) Having done so much work over the past couple of years which made the shed neccessary, I now feel she can sit outside. There is still plenty for me to do inside and would love to be able to light the Reflex Diesel heater and luxuriate in the winter while sitting and soaking up the atmosphere with a tot, staring at all the improvements I plan to make. Not possible inside a hall. Temperatures here are similiar to UK in winter although it does drop regularly to around minus five at night or more. I just wondered what the pro's and cons of leaving the masts up (ketch) are? It would of course save money and hassle although I appreciate if I need to work on them over the winter it would be limited. I feel that lifting them off and on again is more stressful for the boat than leaving them on. What are your views? However, I would have to change yard as the crane here is not capable of lifting out with masts up unfortunately. The cost of wintering would halve!!

 

[Refueler]

Re: Mast(\'s) Up or Down out of the water??

All boats are subject to forces that act on the hull shape when in / out of water. A hull, deck, rigging fittings, hull to deck joint etc. are designed with hull fully supported in water. This provides maximum support.
Blocking of a hull in a yard puts localised and often slightly out of true stresses / support to a hull. You may not see the deformity but it is there.
A simple test is to 'twang' or rig-tension while boat afloat and then do same when blocked off ashore. You may find differing results.
Based on above - it is better to take mast down, which also reduces wind stresses imposed on the boat where it is unable to 'move' to the wind being blocked of.

But saying that - most people do leave masts stepped while ashore. I used to but now don't. Main reason for me is that when I hire the crane to come to my house to lift the boat - I don't want all that grease mess from his wires on my rigging !! Plus of course the maintenance work I do each winter on mast gear.

I'm trying to remember the technical word for the deformity of the hull when stressed by blocking of and rig still tensioned up. There is a proper term for it. In extreme cases where boat is laid up for years and still fully rigged - the deformity can become partly permanent.

 

[Severnman]

Re: Mast(\'s) Up or Down out of the water??

Hogging and Sagging....

 

[Refueler]

Re: Mast(\'s) Up or Down out of the water??

[ QUOTE ]
Hogging and Sagging....

[/ QUOTE ]

Tehnically Hogging and Sagging is IN water ... it's a stress term we use when calculating ships cargo and structural condition.

No it's a term in the same league as elasticity - actually refers directly to the hull form being able to take up the shape dictated by the blocking off and rig stresses.

 

[Marsupial]

Re: Mast(\'s) Up or Down out of the water??

I think that boats are better off in the water - for a start its warmer and as you have said the hull is supported all over.

Ashore you should reduce the tension in the rig or take the mast off the amount of sag can be significant and the rig will have to support it all. (check engine alignment in and out of the water and you will begin to get an idea of just how far all boats "move").

As for the hull, if its GRP them think of it as jelly, supporting it in 6 or 8 places for a long period of time will change its shape. BUT in your case the temperature is very low so it will be more set perhaps - I dont know.

Look at it this way at least you get to have a close inspection of the mast heads every year without going aloft, only the seagulls see mine close up on a regular basis! good ole 7X50's have to do for me!

 

[Blueboatman]

Re: Mast(\'s) Up or Down out of the water??

Since you are planning to do work outdoors on the boat, one question is: Will the masts and rigging be in the way or will they be useful for rigging a cockpit cnaopy between the two masts ?
Now in my opinion I would not go to the expense of removing the masts until such time as you need tto actually work on them. Though I would run off the running rigging and replace with 'string'.

People automatically assume that a boatyard , like a garage, is thoroughly professional because they charge,well, professional rates....

Unless you are there to watch the masts being pulled out, and stored correctly I would be wary of unmasting simply because there are so many bits to get bent in the process- if a spreader root is unfairly loaded, or a turnbuckle gets capsized and then twisted, you will be the first to know about it, probably when sailing..! A bit pessimistic perhaps but I have stepped and unstepped an awful of masts, and boatyards can be under a lot of pressure to use semi skilled help (learning on the job,your boat) and to keep costs reasonable so try to do as many masts as possible on a fair day..
Of course I assume that you are insured and happy to have the boat outside in a suitable cradle where it wont blow over if masts on.

 

[NormanS]

Re: Mast(\'s) Up or Down out of the water??

Re Swanny,
It all depends how sheltered the location is, and also whether you have a good cradle, or are relying on shores. If reasonably sheltered, and preferably with long keel and good cradle, it's fine to leave them up, as I do, and save all the hassle. You can also be guided by what others in the yard do.

 

[srm]

Re: Mast(\'s) Up or Down out of the water??

Prefer mast down, having spent a very worrying hour waiting for crane driver to have his lunch with mast still up and boat ashore. Boat was safely on legs on hard standing but wind was a full F8 and the vibrations in the rig and hull were frightening. Normally I took mast out before lifting but there was too much swell along pier hence the 'mast up' lift.

When I first started being interested in cruising yachts in the late 60's no one put a boat ashore with masts up over the winter. Now they even leave the sails and dodgers etc on, so its not surprising that every now an again we see pics of yachts falling like dominos during the winter.

 

[pmyatt]

Re: Mast(\'s) Up or Down out of the water??

It's worth remembering that boats are built without masts initially but that, hopefully, the designer built in enough re-enforcement/support/overbuild to cope with rigging stresses - hogging etc. In days of yore, wooden boats lived in the water all-year-round - only take masts down when you need to work on them. If the boat is GRP then the choice is yours. Having had the mast of Forever Freedom out for the first time in 19 years I now plan to do it alternate years - and that's on a boat I live aboard and go up the mast at least once a month. Believe me, whatever the cost, the relief at having been able to check every aspect of the mast, rigging, sails, mast electrics, instruments etc., at ground level, gives you a self-righteous glow, no matter what the cost.

 

[swanny]

Re: Mast(\'s) Up or Down out of the water??

Sounds like masts off then. At the current yard I am always there to help (guide, instruct, annoy) the yard chappy. He broke my wind meter spinning thingy last year and I had a job to find a replacement. His crane driver left him and he took up the job and as such I was one of the first to be lifted out. After my masts, he learned that the strop should be much higher on the mast to avoid the mast foot performing huge swinging arcs as he jerkily swung it ashore. He has been much better since then. I think on reflection I would feel better taking them off. I'm the kind of guy who doesn't sleep soooo well at anchor in a bit of wind and perhaps the same would be the case in a winter storm thinking of poor Cocoro canting this way and that. The real saving would be to leave her outside with masts up but my yard can't lift out with masts up and his trailers are truck style chassis types (homemade) with pneumatic tyres which have been known to deflate over the winter!! Imagine that with a mast up! The nearest yard that can do it with stable cradles only saves me four hundred euro and I go from inside to outside. So, it's status quo I reckon. Thanks guys, you helped my dilemna.

 

[chrisc]

Re: Mast(\'s) Up or Down out of the water??

We are in the process of moving from one yard to another (on west coast of sweden) a major difference between the two yards is that in the new place we can keep the mast up for the winter therebye saving time in spring and autumn.As we always take the mast up and down ourselves there are no financial considerations.
however the safest our boat ever felt overwinter was in S of france with the boat out of the water with, mast up,no problem from Mistral but well supported all the way round -better to have realy well supported boat on land with mast up than bad cradles with mast down. Just my opinion..

 

[jan2]

Re: Mast(\'s) Up or Down out of the water??

I am trying to decide between a long keel and a bilge keel - I want the versatility of a bilge keel for shallow water but have heard they are slow to right and have no idea how they handle in the open ocean. Do I have to choose between versatility and safety? I like wood hulls but am not sure if that limits my choice of hull design. I have heard I should have metal fins on the bilge. Any advice?

 

[Bilgediver]

Re: Mast(\'s) Up or Down out of the water??

Prefer mast down, having spent a very worrying hour waiting for crane driver to have his lunch with mast still up and boat ashore. Boat was safely on legs on hard standing but wind was a full F8 and the vibrations in the rig and hull were frightening. Normally I took mast out before lifting but there was too much swell along pier hence the 'mast up' lift.
***************************************************

All to many folk do not consider the wind loading on a mast and the tipping forces it applies. We only have to look at the headlines of previous winters where boats have blown over like a pack of cards .

One of the universities did a study of these forces for a cradle manufacturer and the results were very disturbing and probably much higher than many folk realise.

The decision should not be based on convenience or hull forces imposed by the rigging, but is the boat safe ashore with the mast up in a force 8 ???