What makes a fast Int.Sunfish?

[kmcfast 6]

Looking to start Master Sunfish racing?

[Flyingfish 20]

Here is a good rigging guide to get you started. https://www.starboardpassage.com/sunfish/

For a boat, avoid 2020 LP Sunfish due to reported issues with decks cracking. Avoid all Chinese made LP Sunfish.  LP boats up to 2015 seem good, as do Vanguard and Sunfish-Laser boats.  Get a new racing sail, and any of the class legal composite boards are fine. Wood and composite rudders are equal in performance.  Get a long hiking stick and a good line package and you are ready to go.  

[kmcfast 6]

Thx flying fish the flat sided original rudder and dagger boards are as fast as the new ones with  naca foil section?

[Flyingfish 20]

All the rudders are flat sided, so no differences between them.  The old flat-sided daggerboards cannot keep up with the foil-shaped boards. You cannot be competitive with one. 

[PaulK 591]

Fast boats around here seemed to have very low booms. Going for a decksweeper effect?  

[Major Tom 562]

Probably the most important thing is the nut on the end of the tiller.

[fastyacht 2,594]

3 hours ago, PaulK said:

Fast boats around here seemed to have very low booms. Going for a decksweeper effect?  

And more effective power less heeling moment

[Steve Clark 1,014]

You want a light boat. 128 was the minimum,  internal foam has 2% porosity by volume, so Sunfish get heavy if they aren’t cared for very nicely.  Good news is that inspection ports and  fans dry out wet foam quite nicely. Sometimes foam blocks break away from the hull.  It can be fixed, but if you can avoid it, do.

 

There are other systemic weaknesses. Look for gel coat cracking on the bottom where the dollops of putty that bond the tub to the hull will show up.  The deck aft of the forward edge of the tub is also prone to fatigue if the boat has been raced hard. The deck flexes the harder you roll tack.

Veteran Fish sailors know:

The  aluminum plates that attach the tiller to the rudder aren’t stiff enough, double them up, epoxy bond them to the tiller and backfill the bolt holes with epoxy to prevent them from wobbling and ovaling the holes.  

Booms break at the gooseneck.  Stuff a sleeve ( made from a broken boom with a slice taken out of it) inside.

Same for the mast.

The factory direct setting of rudder sweep relative to keel line is not optimized. Check it modify the blade until it is.  A more vertical blade reduces the force required to turn it. People will call it weather helm, but they are confusing the rudder’s balance with the boats tendency to turn into the wind.

The Sunfish rig is very tunable. You can vary where the gooseneck is positioned on the boom and where  the halyard is tied to the gaff. You can pull the gooseneck down with the tail end of the halyard.  There are other magic things like The Jens that enable you to do other fun things.  Typically racers keep the tack pretty close to the deck and move the gooseneck aft the harder it blows.

SHC

 

 

[Rum Runner 408]

Go to the Sunfish Class Assn. web site. There are a lot of tips and tricks posted there. Also join the class so you can go to sanctioned events.

[Xeon 379]

TBH the simple answer to the question is, a fast sailor 

[Rodfavela 69]

On 11/16/2020 at 7:46 PM, kmcfast said:

Looking to start Master Sunfish racing?

Sail it flat upwind even if you have a little lee helm.

Gooseneck position range is 16" to 22" from the forward edge of the boom . The stronger the wind, the  longer the distance . This moves the center of effort forward and balances the rudder as well as lowers the sail plan.

Heel the boat to windward during the runs.  Sail by the lee. Careful on sitting to far back...tapered sterns like the 'fish's tend to be draggy.

Upwind in port tack can trim harder than starboard tack.

Surround yourself of better sailors and watch, learn, copy.

Good luck

 

[Steve Clark 1,014]

18 hours ago, Rodfavela said:

Upwind in port tack can trim harder than starboard tack.

This is because the sail is not on centerline.  The fact that the gall and boom are to port of the mast means that the sail is not assymetrical just because of the mast but the sheeting angle is different as well.

When I used to race Fish, I tied my main sheet ~3" off centerline so the boom was parallel  to centerline when sheeted hard.  I was never great because I was about 60 pounds heavier than the boat liked.

SHC