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Cruisin' Threads => Tips & Techniques => Topic started by: Bill NH on August 29, 2007, 09:36:03 PM

Title: Unstepping mast (the old way)
Post by: Bill NH on August 29, 2007, 09:36:03 PM
After the local yard quoted over a hundred dollars to unstep my mast (even more expensive than the haulout), I decided to do it the old fashioned way...  After consulting the ultimate traditional sailors reference (A Young Sea Officers Sheet Anchor, or a Key to the Leading of Rigging and to Practical Seamanship by Darcy Lever (London, 1819)) and a trip to the local builders supply for materials (about $70), I rigged a set of shears and a tackle. [see photos I've uploaded, in this case a picture is easily worth a thousand words] 

The shears are two poles joined at the top to make an A-frame of sorts.  I built mine out of 1.5" metal electrical conduit, 2 ten foot sections each side sleeved with a five foot 1.25" piece at the joint and butted with a coupling.  The shears sit on wooden blocks to distribute the deck load and their bases are tied off to the midships cleats to prevent them from sliding when the shears are raised.  Lines were run fore & aft as stays to hold the shears upright just aft of the mast (important to pass the forestay line through the triangle above the spreader).  I rigged a lifting tackle from the head of the shears to a loop secured loosely around the mast.  The loop was allowed to slide up the mast to a point about 1.5 ft below the spreaders, as I estimated the center of gravity of the mast to be about 3 ft below the spreaders and one wants to be just above that point.  I had rigged a line to keep the loop from riding up higher, which I secured to the base of the mast.  I then took a strain on the tackle and disconnected the remaining stays and upper shrouds (the lowers and inner stay were disconnected earlier).  It was only necessary to raise the mast a couple inches to lift the base off the step, after which my wife walked the base aft as I lowered the mast down.  It went very easily.  When it was horizontal I secured the line and then removed the spreaders and bundled the wires to the mast.  With one of us on each end we then eased the line, removed the lower block loop, and carried the mast off the boat and onto the dock.  Never even needed the horses I had set up on the boat. 

The neat thing is that the shear sections can be broken down, so they could be carried on a trailer (or on my pickup rack) easily.  Plus now I have them, so every additional step or unstep of the mast is free.  And the job was easily done by just my wife and me.  First time took about 1.5 hours to set up, unstep the mast and break down, but next time will be under an hour.

Needless to say, the boatyard was surprised when I showed up for my haulout yesterday with the mast already down!

Anyhow, just happy how smoothly it all went and wanted to share this low-tech solution.  Here's to the skills of days gone by!

Bill
Title: Re: Unstepping mast (the old way)
Post by: Captain Smollett on August 29, 2007, 09:46:25 PM
Hi Bill,

Yes, sometimes the old ways are best.  Did you miss CapnK's description of how he did essentially what you describe, but with LADDER as the shears? 

Grog to ya, mate. Good job.
Title: Re: Unstepping mast (the old way)
Post by: BobW on August 29, 2007, 10:22:21 PM
I used the same method to unstep Prelude's mast last year to change out the standing rigging.  I used one 10' and one 8' length of 2x4, sistered with 1x4s.  The legs sat on small plywood pads, and were semi-secured with line to whatever attachment points were convenient (stachions, etc.).  We had the same experience - much longer to set up the first time.

(http://img.photobucket.com/albums/v612/BobWessel/f70706c5.jpg)

The center of gravity on the mast was right at the spreaders.

When it was time to raise the mast a couple of the marina regulars gathered to watch.  They were amazed at how quickly and easily the mast went up.

It's pretty cool when something so simple works so well.
Title: Re: Unstepping mast (the old way)
Post by: Bill NH on August 29, 2007, 11:06:27 PM
Didn't see CaptK's writeup, it was before I joined - but just went and found it...  a ladder, now that's creative!  These all show that weight isn't a big factor at all.  Just need a place to hang your block & tackle!  One advantage of shears is that they don't need to be guyed side to side.

If anyone in northern New England wants to borrow the poles, just give a shout.
Title: Re: Unstepping mast (the old way)
Post by: WayneS on September 02, 2007, 06:13:53 PM
Very nice.  Sounds like you folk have deck-stepped masts.   Anyone got any recommendations for keel stepped masts, and lowering and raising a mast which has five feet of bury?  In that case, you have to haul the mast up four or five feet farther to remove, so need a bigger A frame; and you have a bit of a problem, I should think, in getting the mast through the deck or cabin top without damage to mast, deck or cabin top.

If the A frame works in that sort of case, it would be a great advantage to me.  But there are times when I wouldn't have much-- maybe any-- help, and so could not rely on one person providing muscle at the A frame winch or pulleys, and another at muscling the mast through the partners and onto the step.

At one time I tried designing something which would mount on the boat's trailer, and could later be stored on the trailer.  Came up with some great ideas for Rube Goldberg- ish contraptions, but all would have taken a lot of setup time.
Title: Re: Unstepping mast (the old way)
Post by: Fortis on September 03, 2007, 01:53:37 AM
The only method I know that works for improvised removal of a keel stepped mast where the boat has a decent cabin height is to use a bridge. Does not have to be a huge tall bridge, or it can be one taller then the mast...but it involves an accomplice or two and some ropes, as well as judicious use of the motor and anchor to get into position. You can figure it out from there.

If I was being asked to design something that worked for a trailer-sailer (adn what kind of TS has a keel stepped mast???) I would get a lever arm as long as the trailer that stayed strapped down to it in a way that would not interfere with the boat. It would then connet into a socket on the trailer neck and up through the bow-roller of the boat, until it was ppositioned above the mast socket. The lever arm would have a block on the end of it so that it could hoist the mast vertically for some distance. The trailer would have a remote controlled power winch for the retrieval cable for the boat, and this would also double to hoist the mast. Using the remote would allow one person to guide the mast as it was being raised or lowered.

The term "Windless day" woudl also apply...but then why do you need the mast?



Alex.
Title: Re: Unstepping mast (the old way)
Post by: KenR on September 03, 2007, 04:18:11 PM
Once assisted my sailing instructor in unstepping a mast by rafting up another boat and using the main halyard of the second boat to raise the mast. Very simple and quick - other than the torrential downpour that was going on at the same time.
Title: Re: Unstepping mast (the old way)
Post by: AdriftAtSea on September 03, 2007, 05:20:17 PM
Actually, Ken's suggestion makes a lot of sense..if you have a friend with a boat with a tall enough mast... you might be able to do this without resorting to a bridge.
Title: Re: Unstepping mast (the old way)
Post by: Bill NH on September 04, 2007, 12:34:54 PM
You're right, an A-Frame, shears, ladder or whatever all require at least one willing accomplice.  If you really want to do this solo you might think about fabricating a tabernacle for your deck stepped mast.  With a tabernacle there are many successful rigs using the boom and a trailer winch for solo mast-stepping...
Title: Re: Unstepping mast (the old way)
Post by: WayneS on September 04, 2007, 11:53:38 PM
Thanks for all ideas.  I've actually met someone who used an interesting variant of Ken's idea, and said it was pretty much de rigeur where she came from.  You get TWO buddy boats, both with masts taller than yours.  You run a line from the masthead of one to the masthead of the other, with a block in the middle, line running down appropriately.  You position the victim boat in the middle and hoist out the mast.  Sounded doubtful, but she said it worked well.

Fortis' idea is a bit similar to ones that I have had.  But I would need a 32 foot piece of rectangular-section  steel, and braces on each side of this long arm.

TraveLifts and cranes start to sound pretty good.
Title: Re: Unstepping mast (the old way)
Post by: Fortis on September 05, 2007, 08:36:45 AM
NO, YOU DO NOT. YOU DO NOT NEED TO LIFT A MAST FROM THE TOP!

Ideally, a mast is lifted from around the spreaders, thsi gives you a balance that is "down" but still allows you some easy wobble and manuevuring room.

It is even possible to clamp a weight of some ten or fifteen kilos to the lowest exposed part of a mast and therefor lift from even lower.

So you do not want to hoist your mast fomr the top, if nothing else, it is very fragile and vulnerable up there! Anything reasonably above the balance point will do, and the balance point can be screwed with by making some clamp-on weights (Aluminium mast sections don't weigh much, so 15more kilos at the base will really change the balance point a LOT)

Give it a try.


Alex.
Title: Re: Unstepping mast (the old way)
Post by: KenR on September 05, 2007, 01:39:48 PM
Right about lifting at the spreaders. From that point the balance was very manageable and we were able to raise then lay the mast down very simply and safely. Although there were two of us at the time, I would not hesitate to do it alone on my own boat.
Title: Re: Unstepping mast (the old way)
Post by: CapnK on September 05, 2007, 04:09:11 PM
I've heard of the "2 buddy boats" solution, and I think that that would be easier than just one BB, since you'd be giving the stick more of a vertical pull/drop.

And to add: Hoisting from a point closer to the middle of the mast (by spreaders) also makes it easier to move the spar around (shorter moment arm), and facilitates laying it down gently without cramming the foot into the ground.
Title: Re: Unstepping mast (the old way)
Post by: Ol' Coot on September 09, 2007, 04:30:54 AM
Quote from: Fortis on September 05, 2007, 08:36:45 AM
Ideally, a mast is lifted from around the spreaders, this gives you a balance that is "down" but still allows you some easy wobble and maneuvering room.

If you have a fractional rig, don't assume the spreaders are the correct location to lift from.   Be very careful to actually find a point slightly above mid-height of the mast.  Being even a little top heavy can create a surprising "kick" when the mast comes off the step, especially on a boat that is still in the water and free to move around a little.
Title: KISS at work...
Post by: w00dy on January 01, 2013, 09:15:16 PM
For the last couple of months I have been mentally preparing myself for our winter boat project. Last week, we took the first big step in the process and took the standing rig off the boat.

Utilizing our handy-dandy mast tabernacle and some good ol' gravity, the only extra equipment involved were some additional lines, blocks, and a few more helping hands. Textbook.

(https://lh3.ggpht.com/-VPF_FndrFbQ/UOE4NBTLM0I/AAAAAAAABMs/vsQIuzSa5I4/s1600/maststep+060.JPG)

Don't let the armchair sailors, internet prognosticators, and ankle-grabbers of the world tell you what can or can't do without a crane, engine, 40 ft boat, or college degree.

(https://lh3.ggpht.com/-kGrDrSY6w_c/UOE4WUqsaLI/AAAAAAAABNE/p-KYS27pr_g/s1600/maststep+063.JPG)

Tell them to KISS it  ;D
Title: Re: KISS at work...
Post by: Capt. Tony on January 01, 2013, 09:27:47 PM
Hey, nice going!  I know it is really hard to take photos and do certain tasks concurrently without videoing yourself at work, and who in their right mind would dare do that.  So the before and after pics speak volumes.
Nay sayers abound.  If we actually listened to them what would get done?  If you can't do it..learn it and try it again is my way to beat them.
By the way, what are you doing there?
Title: Re: KISS at work...
Post by: Wade on January 01, 2013, 10:27:32 PM
Love it!
Title: Re: KISS at work...
Post by: w00dy on January 02, 2013, 11:15:42 PM
If I understand your questions correctly, you are probably referring to a friend who was up on deck as a "floater", while I was back in the cockpit, letting out the main-sheet very slowly. Another friend was on the dock with the camera at the time. It was a nice feeling to have so many hands available that someone could be solely taking photographs throughout the process.