Rocket interceptor sail on Sunfish

It certainly doesn’t look like it.
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To me it looks like it might. The sunfish boom will be plenty long and will need to be cut down. The yard may or may not be long enough.

If you really want to know reach out to Dave Clark who builds the Rocket.

Another option that's very simular is Kevin Farrar in New London CT. He builds a very simular sail for the Sunfish. He developed them for the sailors in Sag Harbor Long Island, they love to race and tinker.
 
Probably best to call Fulcrum and ask. The sail is designed to be rigged differently and I would be surprised if a standard Sunfish boom could handle the load shown in the pic. Also, the Rocket sail may not adapt well to a boom with Sunfish rigging - its probably designed for this center boom sheeting.
 

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The Sag Harbor guys haven't been complaining about the standard boom breaking, I wouldn't worry about it.

However, I do think the interceptor type rig would benefit performance and control wise from a stiffer boom.

With the foot attached to the boom like the regular sunfish sail, the rig depowers when the boom bends. This is what you're doing with the heavy "vang"*. When you vang the Sunfish hard the bend pulls the sail into a flatter shape. The interceptor type sail being loose footed will do the opposite, bending the boom will increase the draft of the sail as the effective length of the boom is shortened. This leaves you with gust response of your sail powering up. You can clearly see the boom bending in the photo attached in the previous post.

The flexibility of the yard however should help you in the gust, with the leech tension dropping and the head twisting off in the gust.

Finn sailors have been playing with different stiffness masts for the past 60 years. Softer masts for heavier wind and lighter sailors, most competitive Finn sailors have multiple masts with different stiffness.

* is it really a vang when it doesn't really control sail twist? I've always felt calling it a vang on sunfish was confusing because its use on a sunfish is so different then most other modern types of rig...
 
Fulcrum says it won't fit and suggested I buy a rocket. I'll try one from Peter; I know it fits a Sunfish!
Fulcrum also won't ship to Canada.
 
“The Sag Harbor guys haven't been complaining about the standard boom breaking, I wouldn't worry about it.”

As long as they are using the standard Sunfish rigging, I wouldn’t expect them to have a problem. If you try mid boom sheeting as shown on the Interceptor using a Sunfish boom I think there could be issues.

Anyway, hope the OP calls Fulcrum, gets an answer and lets us know.
 
Fulcrum says it won't fit and suggested I buy a rocket. I'll try one from Peter; I know it fits a Sunfish!
Fulcrum also won't ship to Canada.
That it does. The few people who used mid boom sheeting in the SH fleet (which I used to sail in) also had carbon booms - they are a very creative bunch. I still have one sail remaining if anyone wants it.
 
While we are on the subject of Rocket/Sunny compatibility, does anyone know where to find details of the rigging? I did some quick internet sleuthing but did not find much. I saw one video that mentioned using spectra line as the gooseneck. And somehow the halyard and “vang” (gooseneck downhaul) were one line. It occurred to me I might be able to use line instead of the eye screws to join the spars. That gets rid of a sharp metal piece that can scribe a nice semi-circular scratch into the deck if one is not careful.

I’m not sailing one design. Just goofing around and having fun with the boat. I’d buy that last remaining higher aspect sail if I had the funds but have a limited budget for the boat as I have another that is way more costly.

For the rest of these minor rigging upgrades I have a ton of small blocks, cleats and line to use at no cost.

Erik
Sunfish “Small Axe”
Port Hadlock, WA
JAAAH RAAASTAFARI!
 
The Sag Harbor guys haven't been complaining about the standard boom breaking, I wouldn't worry about it.

However, I do think the interceptor type rig would benefit performance and control wise from a stiffer boom.

With the foot attached to the boom like the regular sunfish sail, the rig depowers when the boom bends. This is what you're doing with the heavy "vang"*. When you vang the Sunfish hard the bend pulls the sail into a flatter shape. The interceptor type sail being loose footed will do the opposite, bending the boom will increase the draft of the sail as the effective length of the boom is shortened. This leaves you with gust response of your sail powering up. You can clearly see the boom bending in the photo attached in the previous post.

The flexibility of the yard however should help you in the gust, with the leech tension dropping and the head twisting off in the gust.

Finn sailors have been playing with different stiffness masts for the past 60 years. Softer masts for heavier wind and lighter sailors, most competitive Finn sailors have multiple masts with different stiffness.

* is it really a vang when it doesn't really control sail twist? I've always felt calling it a vang on sunfish was confusing because its use on a sunfish is so different then most other modern types of rig...
Maybe there should be a vote on a new name. Like a “snooker” or something.
 
FYI, I still have one sail for sale - it is in a storage tube ready to go and I'd like to get it out of my garage. Dropping the price to $300 plus shipping. It does not come with spars but it fits on regular Sunfish spars.
 

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