Sunfish Failure Points?

sharnett

New Member
I've been sailing my Sunfish on Lake Ontario for about 15 years, often in very rough conditions, so my boat has taken a good pounding. I am conscious of the stresses on the mast and the cleats and in reading the forum I was alarmed to learn that the cleats are backed up by wooden blocks. Based on what I've read on this forum, my boat was manufactured between '72 and 87. I need to see if I can find the serial number. My boat doesn't appear to leak, but I haven't weighed it.

Any comments or opinions on the following would be greatly appreciated:
- What are the typical failure points?
- Any thoughts as to how I might test the integrity of the wooden blocks?
- How about the mast hole / step?
- Bonding of the foam blocks?

These seemed like questions that would have been asked before, but I wasn't able to find answers. If so, I apologize.

Thanks!
 
With my Laser & Minifish, the greatest pinpoint stress locations were:

1) Mast step, since all the drive created by the rig above is transmitted through this step.

2) Daggerboard well or trunk, since it is subjected to significant stresses with the daggerboard down and the boat under way... the higher the breeze & the rougher the surface chop, the greater the stresses.

3) Pintles & gudgeons for shipping the rudder, these often work loose over time due to forces on the rudder, and because folks sometimes forget to loosen the rudder line or raise the rudder a bit before beaching (yes, I've been guilty of this once or twice in decades past, LOL).

The other fittings, marine hardware, rigging & sail aboard my boats, well, they generally didn't receive as much abuse, partly due to my penchant for upgrading fittings, hardware, rigging & sail BEFORE equipment failed. And if something failed, I automatically replaced it with something BETTER which would withstand the abuse, particularly when sailing through shark-infested waters off the northern end of Baja. :eek:

Of course, I wasn't limited by any class rules or regs, just sailing each boat for recreational purposes... call it "high-performance recreation" in those glory days, LOL. So upgrades were welcome, even if that meant ponying up some cash, as the peace of mind was totally worth it. You know the old saw: "An ounce of prevention is worth a pound of cure." This holds especially true in the nautical world, where MARINE SAFETY is a serious factor to be considered. :rolleyes:

Just an observation or two from this old small craft sailor, nothing worse than having a primo party voyage or beach patrol interrupted or ruined by equipment failure, and later discovering that the failure could've been prevented by spending an extra $5 or $10 on some fitting, LOL. I've seen my share of equipment failures at sea too, which is why every little detail is important to me. If something looks sketchy or cheesy, swap it out, and damn the cost. ;)

HOPE THIS HELPS IN SOME WAY... THINK I'M ABOUT READY FOR THAT FIRST COLD BEER, AYE? CHEERS!!! :cool:
 
With my Laser & Minifish, the greatest pinpoint stress locations were:

1) Mast step, since all the drive created by the rig above is transmitted through this step.

2) Daggerboard well or trunk, since it is subjected to significant stresses with the daggerboard down and the boat under way... the higher the breeze & the rougher the surface chop, the greater the stresses.

3) Pintles & gudgeons for shipping the rudder, these often work loose over time due to forces on the rudder, and because folks sometimes forget to loosen the rudder line or raise the rudder a bit before beaching (yes, I've been guilty of this once or twice in decades past, LOL).

The other fittings, marine hardware, rigging & sail aboard my boats, well, they generally didn't receive as much abuse, partly due to my penchant for upgrading fittings, hardware, rigging & sail BEFORE equipment failed. And if something failed, I automatically replaced it with something BETTER which would withstand the abuse, particularly when sailing through shark-infested waters off the northern end of Baja. :eek:

Of course, I wasn't limited by any class rules or regs, just sailing each boat for recreational purposes... call it "high-performance recreation" in those glory days, LOL. So upgrades were welcome, even if that meant ponying up some cash, as the peace of mind was totally worth it. You know the old saw: "An ounce of prevention is worth a pound of cure." This holds especially true in the nautical world, where MARINE SAFETY is a serious factor to be considered. :rolleyes:

Just an observation or two from this old small craft sailor, nothing worse than having a primo party voyage or beach patrol interrupted or ruined by equipment failure, and later discovering that the failure could've been prevented by spending an extra $5 or $10 on some fitting, LOL. I've seen my share of equipment failures at sea too, which is why every little detail is important to me. If something looks sketchy or cheesy, swap it out, and damn the cost. ;)

HOPE THIS HELPS IN SOME WAY... THINK I'M ABOUT READY FOR THAT FIRST COLD BEER, AYE? CHEERS!!! :cool:
Thanks! Those are all good suggestions. Like you, I'm just sailing for fun and am looking for reliability. I'll gladly spend the extra cash to upgrade wherever possible with no regulations to worry about. Most of my concern has to do with not being able to inspect problem areas.

On this hot day the first one will be my homebrew Pilsner, then a nice IPA.
 
An inspection port a bit aft of the splash guard would allow a peak at the mast step and the structural foam.
You would also find out whether the hull is dry (or not) and inspect some of the backer blocks.
And following up on Charles' concern, masts do break; I don't know if a boat that old has the interior sleeve.
 
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I've been sailing my Sunfish on Lake Ontario for about 15 years, often in very rough conditions, so my boat has taken a good pounding. I am conscious of the stresses on the mast and the cleats and in reading the forum I was alarmed to learn that the cleats are backed up by wooden blocks. Based on what I've read on this forum, my boat was manufactured between '72 and 87. I need to see if I can find the serial number. My boat doesn't appear to leak, but I haven't weighed it.

Any comments or opinions on the following would be greatly appreciated:
- What are the typical failure points?
- Any thoughts as to how I might test the integrity of the wooden blocks?
- How about the mast hole / step?
- Bonding of the foam blocks?

These seemed like questions that would have been asked before, but I wasn't able to find answers. If so, I apologize.

Thanks!
The mast step integrity is an easy one. Fill it with water, and if the water level stays "topped up" overnight, it's OK.
 
An inspection port a bit aft of the splash guard would allow a peak at the mast step and the structural foam.
You would also find out whether the hull is dry (or not) and inspect some of the backer blocks.
And following up on Charles' concern, masts do break; I don't know if a boat that old has the interior sleeve.
The inspection port is another good suggestion. I'm not aware of the interior mast sleeve. Will it be visible when I pull the caps off?

I feel a bit like some folks I've known that just get in and turn the key on their vehicle, expecting it to work every time without maintenance. I've been putting the boat in the water and sailing without thinking too much about the hull. It's becoming clear that this is something I should have thought about a month or two back. I'm ready to go out sailing!
 
Mast sleeves have only been around about 15 years. Some racers were able to bend their masts in heavy air so the sleeve was added at the gooseneck.

If the foam blocks detach you’ll hear your hull pounding more, but it isn’t a safety or durability issue. The hull flexes a bit more which bothers racers but it’s nothing that will cause more damage or a failure.
 
Mast sleeves have only been around about 15 years. Some racers were able to bend their masts in heavy air so the sleeve was added at the gooseneck.

If the foam blocks detach you’ll hear your hull pounding more, but it isn’t a safety or durability issue. The hull flexes a bit more which bothers racers but it’s nothing that will cause more damage or a failure.
So I wouldn't have the mast sleeve, but if I did then I wouldn't want to turn the mast over -- unless the sleeve can be pulled out and moved to the other end.
 
I would not worry about the wood blocks as they haven't failed. If the hull is dry they will be fine. Usually when they fail a screw pulls up. Which can be fixed with fiber glass and epoxy in in the hole.
 
Currently your rig is trying to push the mast through the bottom of your mast tube and putting strain on the halyard cleat. Put on a mast cleat. This stops the push on the mast tube and now the deck cleat is used to hold the rig to the hull.
Adding the mast cleat makes a lot of sense, and that way I won't have to worry about the wood block behind the halyard cleat.
 
So...obviously there have been those that lost their rig to the deep....camps, ultra newbies without "forum knowledge", and a vast variety of others. Anybody ever admit to this or know someone it happened to? It'd be a bummer coming home, sans mast, spars, and sail.
 
If you sail in waters over 30ft deep or so, don't have a stopper knot on the mainsheet, I can see the main sheet un-threading itself from the boom blocks, as the rig travels towards Titanic-ville
 
I just wanted to thank everyone for all the great suggestions! I got a look at the serial number and it's an '83. I ordered a mast cleat and an inspection port and a bunch of other things from Intensity Sails. Looking forward to checking her over and putting her in the water soon.
 
Keep us informed how it goes.

Was looking at the sunfish class rules. Even if you don't race it gives you a idea for the mast cleat height we use.

3.5.9 One cleat of any type may be installed on the mast not more than four (4‟) feet from the base.

You want it high enough so it is easy to rig but not to low to interfere with the gooseneck.
 
Another reason for the 4 foot placement is if you are on the water and need to get the sail down in an emergency, that location is easy to reach.
 
What exactly is this mast cleat? The only thing I know of is a little cleat attached to the deck on the starboard side of the mast.
 
What exactly is this mast cleat? The only thing I know of is a little cleat attached to the deck on the starboard side of the mast.
img0175_106.jpg


sunfish-rigging-drawing.jpg
 
So it appears that I don't know how to properly rig at all... Lol
Is there a link for rigging a sailfish with this incorporated?
 
So it appears that I don't know how to properly rig at all... Lol
Is there a link for rigging a sailfish with this incorporated?
You have to buy a second one, and attach it (yourself) to the mast.

Sheet metal screws—pop-rivets—maybe add some adhesive. (Although I don't know if anything sticks to anodized aluminum for very long).

A cleat the same size as the deck cleat will work. Four feet (or less) from the bottom of the mast.

Anything else is not legal for racing, and could result in an arrest and a fine (not to exceed $250). :D
 
A good suggestion I saw somewhere on this forum is to place a piece of sandpaper on the mast with the abrasive facing out. Carefully rub the cleat base against the sandpaper to make it more perfectly mate with the radius of the mast.

There was also some discussion about fasteners. Apparently the stainless steel screws will galvanically corrode with the aluminum and seize in place. I'm not sure this is a problem, and I think I'm going that route. Never been a big fan of pop rivets and would expect them to work loose.
 

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