Fixing Broken Mast

[jeagles]

I have searched the forums and Google for instructions on repairing aluminum masts. I only find secondary references suggesting that it can be done but only 1 reference to a small mast. I am looking to repair a mast off a 35 sailboat that is completely broken. Can it be fixed/spliced?. Any advice

[Fiveslide]

It can be done with an internal aluminum sleeve fabricated to fit the inside of the mast. Some rigs even come that way from the manufacturer. The sleeve needs to be well-fitting and riveted in place with large rivets of appropriate material so that corrosion is minimal.

This is one of those jobs that you're not going to save a ton of money if you DIY. You're buying new rigging, fabricating parts, paying yard fees and crane fees, fixing the original reason the mast fell. It adds up quick. Perhaps paying a rigger to advise you would only be a small percentage of the costs.

You could also shop for a new/used mast. That is what I did.

Got any pics of the break? Why did it fall in the first place?

[zeehag]

sleeve it. the mast will have no strength unless you make a sleeve for it longer than the break and weld that sleeve in place
welder friend here does that nicely

[ericoh88]

Broken mast from a cat were repaired with sleeves, rivets and al welding. Very nice job. If you want to email the people pm me.

[Island Time O25]

As prev. noted it may be way cheaper to get a used mast form a boat junk yard. Here in New England there are plenty to choose from in MA, RI and ME for about $1,000-3,000, depending on the age, rigging condition, etc. Some will even deliver within reasonable distance. I recall some years ago when I was looking for used sails through c-list, some guy's backyard in RI was full of masts, booms and roller furlers of all sizes and shapes. And prices were very reasonable but no delivery in that case as far as I recall. Also lots of older boas are being parted out all the time so availability should not be an issue. Most likely it'll be the distance or the delivery mode/price which is a deal stopper.

[JPA Cate]

jeagles, please let us know where you are. Then someone nearby may be able to inform you of a trustable rigger in your vicinity, that's one way to start.

Just saying the mast is "very broken" is not quite enough. We were dismasted in a 36 footer in '96. At the time, the new mast, standing and running rigging, and replacing the antennas and radar came to about $US 30,000. It ain't cheap. but the inner and outer sleeving method can work okay. It's worth giving it a go, especially if you are somewhere there are lots of riggers with spare mast bits hanging around, so you can find the right mast sections.....for the sleeving process. The new wire will cost what it costs. Perhaps some of the running rigging is re-usable. Probably, the wire is history.

Ann

[UNCIVILIZED]

The sleeving, along with welding or mechanical fasteners is a common way to build or repair masts. And some are purpose designed to be demountable. Not that they're taken apart a lot, but that to be able to do so is purpose designed into them. Particularly for large spars, as they're too big to transport in one piece, other than with say an Antonov (HUGE Russian cargo plane) or on the deck of a commercial ship.

When you're trying to figure all of this out, it would help if you could post some pics. Along with boat type, her displacement, keel weight, draft, etc. And if you know it, her Righting Moment, or even an approximation there of, so that we can make educated guesses at same.

You'd also be doing yourself a HUGE favor if you buy a copy of Brion Toss's The Rigger's Apprentice as it contains the basic info & formulas by which one can build a mast from a bare tube. Including choosing the tube itself, wire sizes, tang sizes, etc.
There's also a good bit of info on this kind of stuff in the Dashew's Offshore Cruising Encyclopedia which is free for download at their website (get their other books while you're there, they're Outstanding). SetSail FPB » Free Books
And of course there's a lot of info on the various spar maker's websites.

Since you're rebuilding anyway, think hard about what "new" features you'd like the mast to have. Be it a redesigned masthead, such that it can support other components, & or halyard configurations. Redesigned wiring conduits. Etc. And it's a good time to install the hardware or facilities for same, that will allow you to add a spare halyard, or topping lift/staysail halyard, etc. at some point down the road.
By this I mean setting up the spar, & it's ancilliaries so that if you choose to add some of the above, all you need do is hang a block from a crane, or reeve the new halyard. Since in the big picture, sheave boxes, & adding them while a mast tube is horizontal, are cheap & easy. Plus internal halyards are SO much nicer: less windage, less noise, longer life...


PS: Sometimes while mast/tube shopping you'll get lucky & be able to snag various components, super cheaply. Be it a 2nd spin pole, mainsail track system, self-leveling radar bracket, etc.
And don't be shy about putting up "wanted" ads. Sometimes you'll even get lucky & run across a carbon fiber tube that can be repurposed for your use. Which can be a super score. Some guys even design whole cruising boats around such rigs. They can be that sweet.

[neilpride]

Originally Posted by jeagles

I have searched the forums and Google for instructions on repairing aluminum masts. I only find secondary references suggesting that it can be done but only 1 reference to a small mast. I am looking to repair a mast off a 35 sailboat that is completely broken. Can it be fixed/spliced?. Any advice

You dont mention where the mast broke? mid section ? sleves usually are placed above the first set of spreaders, where there is not much bending, otherwise you can make a hard spot in the mast, use eliptical ends in the sleeve piece, that help to mitigate hard spots,, all of this if your 2 mast pieces are true right, check it before because many sticks after a dismast are bend.. SS rivets are fine , placed in a zig zag pattern , and the best advice could be try to found a used spar because after all your repair job is going to be expensive anyway ...