Bent boom.

klemsaba

Member
Crazy sailing yesterday with sustained winds around 25mph. There were a lot of Sunfish out sailing in the cove for protection. I was following my brother-in-law when he got tangled up and collided with another Sunfish. I was doing my best to avoid the crash when a gust hit and the boats rotated around and I sailed right into his mainsheet. This was the result...

IMG_0349.jpg


I was so close to avoiding the mess but my spar snagged and then popped off his sheet and I continued sailing on while the other boats sorted out their issues. Stupid accident I should have been able to avoid. The sad part is I had the only damage from the collision!

Not happy, I decided to go sail the thing across the lake and back with my brother-in-laws and their Sunfish. Boat sailed good in the 25mph winds and waves crashing over the bow. It was the best sail this season! I'm sore today.

The crease is a concern. I think I might try to put some kind of wood dowel screwed/revited in there and flip the boom around and see what happens. Is there more stress down by the gooseneck or towards the outside?

I've done a cursory scan of past threads on bent spars and will spend some more time researching.

Any thoughts or ideas welcome.

Thanks!
 
That's a pretty nasty kink. I fear that if you try to repair with a dowel, the area will still be weak, even with the dowel in it. That said, give it a try and see if it works. You have nothing to lose but your time and the cost of the dowel.

Alan Glos
Cazenovia, NY
 
Totally toasted! Even if you jam a dowel in it the majority of the
strength is gone. You could cut out the damaged section and
insert a aluminum sleeve but for the price of what it's worth
in time and money getting a used boom from Alan is your
best bet. I have a boom that broke in the same area and
has a sleeve welded on the outside but it interferes with
the goose-neck. Remember, a boom that totally snaps is
just another name for a sharpened spear.
 
The crease is a concern. I think I might try to put some kind of wood dowel screwed/revited in there and flip the boom around and see what happens. Is there more stress down by the gooseneck or towards the outside?![/QUOTE]
That should be usable. I wouldn’t worry about the dowel. End-for-ending it should work, or better yet make it a top spar. Probably place the damaged end at the head of the sail.
 
Klemsaba,

I can sell you a good used boom with blocks and end caps for $50, but the problem is shipping as any Sunfish spar is considered oversize and has to be shipped by a freight carrier at big bucks. I am in Central NY, near Syracuse. If you are interested, are you close by or have a way to pick up a spar here?

Alan Glos
Cazenovia, NY
 
I have a pile of wood broomsticks just waiting for just such a misadventure. :cool: Some are older, and made of strong oak! :eek:

Keep in mind that the entire spar bends under wind pressure. (Actually, a pretty sight). One bend is bad enough, but bending it back will make it even weaker. That bend is a major weakness, and I wouldn't stress it any longer.

That's a pretty nasty kink. I fear that if you try to repair with a dowel, the area will still be weak, even with the dowel in it. That said, give it a try and see if it works. You have nothing to lose but your time and the cost of the dowel. Alan Glos Cazenovia, NY
What Alan said. :) How far from one end is the bend?

But to get a free repair while you wait, have an assistant stand on the longer end, and drive a suitably-sized (16"?) dowel while you stand on the short end. If you have various lengths of ½-inch socket wrench extensions, those can be "stacked" to drive the dowel.

.
 
While Sunfish booms bend when sailing in a breeze, some parts of the boom bend a lot more than others. Fortunately for you, the bottom of the upper spar, the outer end of the lower spar, and the outer end of the upper spar don't bend much. That is a pretty decent kink, so straightening it is probably necessary for acceptable sail shape. But if you can straighten it, swapping the booms around should enable you to keep using it for a long time. Just to show how little those parts of the booms bend, I searched around for images from the Sunfish Worlds, where it is often windy and the boats get pushed hard. The pic in the article I have linked to shows what I mean. Smith Wins Division At Sunfish World Champs If I were you, I'd put the damaged part at the lower end of the upper spar.
 
A lot of "seasoned Sunfish" have a lower spar (boom) which is in shabby shape where the gooseneck clamps to it. It's probably the most damaged piece of aluminum spars on our Sunfish. But we can benefit here, because it's also the straightest part in heavy winds.

If it were my problem, I'd insert a wooden dowel, and clamp the gooseneck onto that same 16" area. It would be difficult to crush the aluminum into it's usual uselessness with the clamp, and would assist in straightening that bent part of the boom.

.
 
To expand on what beldar boathead suggests:
Remember that when aluminum is crimped like this the aluminum work-hardens in the area of the crimp, and that area becomes more brittle than the rest of the spar. I would not try to remove the crimp or straighten this spar (= more bending & more work-hardening). I would cut the crimp out and epoxy in a wooden splice sized for a tight fit inside the aluminum spar. I would space the aluminum sections far enough apart (1"~2") on the wood splice to make up for the length lost by the cut out crimp. You want the repaired spar to stay as limber as possible--I would insert the wood splice maybe 12" into each piece of the cut aluminum spar, then reverse/re-rig this spar as BB recommends.
You can get slightly tricky, orienting the grain of the wood splice to produce maximum strength across the width of the spar when in use, etc.
 
Klemsaba,

I can sell you a good used boom with blocks and end caps for $50, but the problem is shipping as any Sunfish spar is considered oversize and has to be shipped by a freight carrier at big bucks. I am in Central NY, near Syracuse. If you are interested, are you close by or have a way to pick up a spar here?

Alan Glos
Cazenovia, NY
Thinking on this some more, I'd be tempted to spend that money on a CraigsList used Sunfish. More parts than you could ever use, and Sunfish spars haven't changed. I'm not sure how I ended up with six Sunfish (now five). :confused:
 
Thanks for the feedback everyone. I should be able to eventually find a 'locally' sourced set of booms that I don't have to ship. I'm always on the lookout for another Sunfish so some parts boat might come up.

When that happens I'll work on experimenting with the broken boom and post back.

Keep the ideas coming if you think of anything!
 

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