mast lowering

wiggy

wiggy

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I have to lower the mast on my MG Spring 25. I do not have access to a crane but do have 2 willing volunteers. I've heard of folks using a spinny pole at the base of the mast to act as a lever to help lower. Any hints and tips much appreciated.
 
Depends on the mast step and the length and weight of the mast. To take down Eider Ducks hefty wooden pole requires two peopl to pay out on a long (and strong) wrp attached to the forestay. The mast pivots back in its tabernacle and four guys take the weight as it is lowered. With a less hefty tabernacle I would need to bodies on guy ropes either side to keep the mast in line.

If the mast is fairly lightweight then th ejob gets easier, unless the mast is keel stepped in which case it gets harder... you need a 4 guys to the masthead to steady the mast as you undo all the rigging & lift the mast from the keel.

Get more people than you think you will need, plan carefully and have a backup for each person. Next time you will really know how many you need.

A quick look at the size of boat I'd say you can do it by hand. You will need five to eight people, and they need to know what they are doing.

I've just bought my first boat where the mast is too big to get down by hand.... Damnshrmngleshnorbits

Have fun

Smiley G
 
This method is possible, I once had to use it on a Sigma 33 but it can very easily go very expensively wrong. The mast has to be securely restrained at its foot, and if you are pivoting on a pin make sure that the shape of the heel relative to the pivot allows full downward rotation, (some Kemp masts did not) the pole needs to be strong in compression, stiff and well secured parallel to the deck, and then allowed to rise under control from the stemhead, the pole rotates upward as the mast goes back, use a purchase, the mainsheet tackle may be long enough for this with possibly a short strop. A critical thing is to guy it laterally as it goes down with a rope (halyards) to each side. You are better with four people, one on the end of each of your three ropes and at least one to take the weight before the mast touches the coachroof, as short and light aluminium ladder can be useful at this point as a strut.
Good luck, proceed carefully, work out before you start every direction that the mast could move and cover it.
 
Ive a westerly 23ft boat. I've had the mast down and up with 3 of us. 4 would have been more comfortable. I'd add 2 things to the other advice, if possible have the boat low in the water and you high up on the harbour. It helps with the forces. Be careful when the mast comes down of ot overhanging the stern - make sure there is clear space. Put your berth cushions on the coach roof. Don't do it if its windy. If you think it through and do it slow you'll be fine.
 
Hey Quandry... what's the length of a Sigma 33 mast! Must be way longer than my Countess 33 ketch mainmast. Blimey... a certain pucker factor must have been in order that day.

Tho possibly not heavier!
 
Sigma 33 about 12m. but easier because it is deck stepped. ( the unstepping of keel stepped masts such as the 38 certainly needs a crane) No, we did not think we were taking any risk until it started to go down and we realized that the screwdriver we were pivoting on was under considerable shear as the hole on the mast heel and step moved out of line. However we were doing it in an empty boat lift dock at low tide so as it got below half way the guys on the dock were able to take the loads and we got our pivot pin out before the casting or the screwdriver sheared, The main lesson we learnt is that the holes on mast steps (unlike tabernacles) are not always positioned or intended for pivoting.
 
If the total mass of a deck-stepped mast is not too great, there is a way of lowering it using a gin pole and the mainsheet. An article on this very subject might be appearing in PBW very soon.

Using this system I lower and raise the mast on my Signet 20 single-handed (literally) as the gin pole along with the gearing of the mainsheet tackle means that the forces involved are very low. It is also possible to stop midway, secure the mainsheet in the jamming cleat, secure the sheet with a couple of half-hitches, and walk away from it to make adjustments if necessary - although I have never found this necessary.

I would not like to try this with a large mast, but mine is about 9m and is nowhere near being a struggle, so I guess up to 12m would be ok depending of course on the mass of the thing.
 
Right. Expert here. Used to work for MG, and had my own Spring.

The mast and rigging can be carried on the shoulder of any fit person. The problems begin with leverage. The CofG of the mast, when horizontal and connected to the deck plate, is behind the transom. Such that when you have dropped the mast to horizontal, a person standing at the stern can only just support the load. But, when you pull out the pin from the step you need to apply a downward force on the foot of the mast. Cumulatively, this will overwhelm the man at the back. (Weight of mast plus downward force at the step). So, two blokes at the back, and one ready to push down at t' front. Then you move the whole thing forwards until all can relax.

Laterally, it's a whole 'nother story. Forget A frames. Take a pair of lines to the masthead on the main halyard. Get a person on either side, preferably 40 feet or so away, to control the sideways movement, with the boat lashed tight so it can't move.

I did it a few times in unhelpful settings. If you want a consultant/witness, I am usually available and drink Guinness.
 
The problems of CofG aft of the transom can be overcome or aleviated by fitting an A frame of wood or a stayed post at the transom for the mast to sit in. This must be as high as you can reach from the cockpit seat ie 2 metres. This means that not only do you have a strong support for the mast but it is supported well above horizontal hence CofG is further forward.
From this position the mast base pivot bolt is removed and the base of the mast moved forward to sit on or under the bow rail. You need a tall helper at the back to lift the mast and slide it forward in steps over the transom support.


PICT0088.jpg


Here is a photo of True Blue a Farr40 with mast lowered while under way for bridges.

Here 2 spin poles are set up to improve the angle of pull of the forestay (or halyard) when the mast is down. You need a 4 purchase tackle and a lot of rope so that the tackle can be taken back to a halyard winch.
The mast must be supported sideways by tension on halyards taken out to the gunwhale which must be retensioned as the mast goes down. (there are other methods)

True Blue has a keel stepped mast which has been cut just above the deck and a hinge built into the mast to facilitate lowering. The mast weighs some 400Kg. The spin poles attach to purpose fitted rings near the gunwhale and aprox adjacent to the mast. Location is selected for spin pole length.

PM me for more info if you are worried. Just do it firstly with lots of helpers until you get used to it. You will never consider climbing the mast again. good luck olewill
 
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I have to lower the mast on my MG Spring 25. I do not have access to a crane but do have 2 willing volunteers. I've heard of folks using a spinny pole at the base of the mast to act as a lever to help lower. Any hints and tips much appreciated.

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If I remember correctly you have similar mast step as I - a vertical blade that sits into a grooved mast fitting. A single bolt that it can pivot on.
The fitting is fine until mast leans to one side and then the force exerted on the fitting is considerable. So you must make sure the the mast does not fall of to one side or other.

I have a heavy alloy mast on my 25ft'r and it takes myself and 3 guys.

I take a line through the bow roller and make of on the forestay at top of rigging screw. (Means I have to lift furling drum out of the way). This then lets me undo the rigging screw while still keeping tension on the stay. The other end of the line is round the fwd mooring post or windlass if you have one.
So to start - line made fast to forestay and tensioned. We let off forestay and backstays so that mast is held by cap and side stays. Forestay of course with line.
1 guy has long plank of 2 x 3 about 2.5m long and props that in cockpit ready. Other 2 guys are standing either side of mast ready to steady it when side stays slacked.
So I then slack main cap shrouds a few cms equally each side but leave connected. Aft baby side stays now slacked same so they do not pull on mast. Mast is now held by fwd baby side stays and 2 guys + forestay to line. Now slack fwd sides and disconnect, mast will likely not move.
I then go fwd to the line and take of post or windlass but keeping one turn so I can control lowering. Once ready I get the 2 guys and 3rd to get mast started on its rearward journey. 2 guys walk back and keep mast from falling to side, 3rd guy wlaks back also with mast then puts prop under it as soon as possible. This is then used to help the last extreme angle part.
The main cap shrouds being still connected will prevent extreme side movement until mast is halfway down.

We used a spinny pole on the mast a couple of times but found it didn't help that much unless we set up extra guys and ropes - which meant more people to tend. No real benefit.

The best for mast work is of course the full tabernacle job where mast base is held inside large plates to help prevent falling to side - but note it can still happen !!

If you want a system to do the mast and don't mind spending a few coppers ... Compass24 have a dedicated mast system that collapses down to manageable size for stowage.

Best advise ? Think carefully and plan ... make sure guys are reasonably strong ... take it slowly, always where possible take precautionary measures with preventer lines. Pick a nice day when boat's not being blown around - that mast has a lot of windage !
 
We do it every year on our 25 footer deck stepped on a pin with an A frame made out of 3*2" wood. Its not that difficult but easiest with 4 people, 1 controling the lowering, 2 holding halyards each side to make sure it stays on the centerline and 4th in charge on deck walking the mast back to lower into the crutch to collect it, being carefull not to get underneath it lest anything should go wrong
 
Done this many times on a 28' boat without drama.


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The problems of CofG aft of the transom can be overcome or aleviated by fitting an A frame of wood or a stayed post at the transom for the mast to sit in.

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That is the key IMHO. I used to simply lash an extending ladder to the stern, lower mast in, lower ladder, make secure and remove pin from deck step, lower ladder more and slide mast forward.

Put some padding on the ladder's top step so you don't grind off the anodising.
 
Block and tackle under a bridge or linkspan at low tide is much safer.
If you can get a lifting force on it above/ close to the mast's cofg you then only have to guide it
Some clubs have DIY crane arrangements.
When it goes wrong, it goes very wrong very quickly.
However you do it, a few extra tall people on hand the first time is worth buying them a pint imho!
 
Hello Nigel The mast base of my little boat 27ft mast is similar to what you describe. ie a spine in the deck and lugs welded to the mast to pivot on with a short bolt as pivot. I consider this a major asset when mast lowering as the pivot is narrow there is relatively little movement for some degree of mast swing sideways. If the mast does swing sideways only the lugs on the mast get opened up a little. By contrast the boats with a base with aluminium lugs about 8 to 10 cms apart witha 12cm pivot pin are wide enough to stop any sideways wing but narrow enough that if there is swing the base lugs snap off. The classic wooden step of 2 posts each side of the mast may be able to take some spreading pressure from, mast swing or may be strong enou8gh to stop the swing. Whatever... the leverage is huge. Don't expect the mast base to stop the swing.

Supporting the mast sideways is vital if doing it on the water when a large Mobo goes by causing the boat to rock. This is perhaps the most common cause of mast lowering problems here at Fremantle.

I have one acquaintance with a heavy 40 ft ast head rig who regularly lowers his mast for the bridges single handed while underway then raises it again. It is just a matter of getting organised and kitted up. olewill
 
Hi Will ... as you know we both have had this discussion before - it's a regular topic in the winter.

I would prefer a full tabernacle with the 30+cms high sides etc. - but then you loose the adjustment to mast position I have now.

My mast base is a solid alloy casting machine screwed into the mast base tube. Halyard sheeves set into it and a slot through centre to take the blade on deck. Any serious side pressure to it would be disaster I reckon !!

SAmast008.jpg


sorry not better photo !
 
what ever you do, ensure that the boat is bow in to a pontoon so the stern is out over clear water, and not the other way round so the rig comes down over the pontooon. I have seen what happens when mast falls and someone is stood there, and it is not nice.
 
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what ever you do, ensure that the boat is bow in to a pontoon so the stern is out over clear water, and not the other way round so the rig comes down over the pontooon. I have seen what happens when mast falls and someone is stood there, and it is not nice.

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Why are people replying to ME ? I do this mast up / down lark everytime I want to get to open water - I have 3 bridges to clear after letting go from back of my house ...

I would like a better way and interested in A frames etc. But I have strapping guys work for me that I detail to attend for mast duties - they've got quite good at it !!
 
[ QUOTE ]
what ever you do, ensure that the boat is bow in to a pontoon so the stern is out over clear water, and not the other way round so the rig comes down over the pontooon. I have seen what happens when mast falls and someone is stood there, and it is not nice.

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No it makes no difference. If the mast falls it usually remains attached to the base so the mast will hit the back of the cabin or stern rail breaking either the mast (I have seen this happen at a boat ramp) or hopefully will tear the base out
If the mast is lowered over a pontoon may be some one or some thing will catch it but best duck if it falls. olewill
 
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