Remove a mast without a crane?

[Ratty1978]

I'm not an engineer, but I hang around with them!
Used an A-frame for a San Juan 24, mast a bit less long, but aluminum, so heavier. Used four concrete trowel poles -- the telescope, so two each side, up about 16 feet. The apex was cobbled together from plywood and 2 x 4s. The only headache was that that particular mast has the center of gravity higher than the spreaders, so the base wants to rise and head fall. But it's all close enough to the lift point that it's fairly easy to manage. I've done it single handed.

Originally Posted by MicHughV

Ok, so this is me, the engineer talking, not me, the sailor. The weight of the mast is not the issue, it's the length. Don't forget to factor in the weight of all the rigging, probably another 100 lbs on top of the mast weight.

The best way to go about this, is to build a simple wood A-frame, that can be positioned adjacent, but just ahead of the mast.
The purpose of the A-frame is not to just to take the mast out, but also to replace it.

The A-frame needs to be as high as about 6' above the spreaders, and can be position on deck or the cabin house, and the peak needs to be fitted with a block and line and the A-frame needs to be braced, once in position. You can use halyard, anchor line, etc, to tie it fore an aft so that it is pretty rigid and won't fall over. As the mast is not heavy, some 2x6's spliced together should do the trick to make an A-frame.
Use a halyard to pull the A-frame up. Tie the halyard to the A-frame with a loose fitting loop. Once the A-frame is in position. you should be able to loosen the halyard to allow the loop to slide down.

Take the bitter end of the line coming from the peak of the A-frame, and make a loop around the mast. Pull this loop, until it comes to rest under the spreaders. I'm assuming a single spreader rig here.

Then undue all the shrouds and stays.

Using the block and line arrangement, pull the mast up so that it exits the deck and gives you 6" or so of clear space between bottom of mast and top of deck. Seeing as you'll be dealing with 200 lbs or more, some additional hands on the line would come in handy. If this is a concern, use a line long enough that you can lead it to a winch, and winch it up. Once up, slack of the line, I trust you know how to do this slowly.

Now you will need one person holding the foot of the mast and walking forward with it, while another person(s) starts to lower the mast. Co-ordination will be required. Lower the mast as the same speed the mast can be walked forward. With the loop at the spreaders, the weight of the mast will be more or less equal around this fulcrum point so should not be overly unwieldy.

By the time, the foot of the mast is at the bow, the mast should be more or less level. Tie off the mast, at the bow and stern pulpits, so you can undo all the rigging.

Once all the rigging is off, you ( with friends) shoud be able to walk the mast of the boat.

Leave the A-frame up, as you'll need it to put the mast bask.

Trust that this gives you some guidance.

As a footnote, there are rental agencies, that might be able to provide you with some or other mini-crane or lift to serve the same purpose as the A-frame.

[El Pinguino]

I assume the boat is on a trailer, if so raise mast clear of boat -move boat from under mast- lower mast.
If boat is not on a trailer then put boat on trailer.

[GrowleyMonster]

The "A-frame", more properly called sheer legs, works nicely if it is tall enough. The taller, the better. Being able to hoist the mast above its balance point is a plus, but even halfway up can work. You just need a couple more guys to help steady the mast in the vertical position, especially when unstepping it. I have done this with 12' 2"x10" pine boards from the big box. Like I said, taller is better, but this can work with a reasonable degree of safety if you have enough bodies available and the mast is under 40' top to bottom. Care must be taken to stabilize the sheer legs in the fore and aft axis. Don't do what I saw attempted once, and rely on gravity and just a single stay. It "can" end badly. You also want to be able to adjust your forestay and backstays for a nice straight drop. Often you think you got it perfect but when you take a strain, everything changes.

I have also seen the boom alone, stayed and guyed to accomplish this but sheer legs is much less fiddley. The only advantage to the boom method is you don't end up wondering what to do with two big ass boards that don't really have a good place on deck for the next time you need them. The boom has a very good place for storage until you need to unstep your mast again! It has a home already. Out of an overabundance of caution you might consider a temporary compression post under where the boom stands up on deck, but I just stuck a piece of plywood between boom and deck and call it good. No problems the only time I ever did it with just the boom. A borrowed spar from a bigger boat could work, I suppose.

A deck stepped mast is so much nicer when you have to step/unstep, and you don't have proper lifting equipment. Some day I will have a boat with a tabernacled mast and everything will be roses and chocolates.

[BBill]

At least there's a lot of free wood in SW Florida from hurricane damage but building a tripod is a lot of hassle compared to $350 for a 35' rental lift from Home Depot.

[GrowleyMonster]

Originally Posted by BBill

At least there's a lot of free wood in SW Florida from hurricane damage but building a tripod is a lot of hassle compared to $350 for a 35' rental lift from Home Depot.

Tripod not necessary. Sheer legs are essentially a bipod. You have lateral stability from the two legs. Add fore/aft stability with jury stays, a forestay and twin backstays. When using only your boom, add jury shrouds, for lateral stability. Or vice versa. I agree, renting equipment is a good option but it is not necesarily hassle free, either, and subject to notice and availability, of course. By the time you get a cherry picker actually delivered, I can already be rigged up and making the lift, one way or the other. I will concede that using rental equipment is less of a technical challenge, though.

For some of us, $350 is actually a lot of money to spend on something we don't even get to keep.

[sailoysterbay]

You can use the halyards to lower the mast. Start with a piece of line a least twice as long as the distance between the bow and the mast head plus the Hight of the mast inside the cabin. Attach the middle of this line to the jib halyard shackle. This will now be know as the bridle. Attach each end of the bridle to each of the bows. Pull the halyard all the way up and have some of your crew lift the mast out of the cabin top and brace it on the deck possible on some cushions. Then slowly let out the halyard while tipping the mast toward the back of the boat and holding the base steady so it doesn't slip. You could also make a three sided box out of plywood to hold the base mast steady. You can attach something like a 4x4 to the bottom of the box and drop in the mast hole so it doesn't slip.
Good luck and let us know how it works out!