Comparing the Minifish to the Sunfish

Weston

Well-Known Member
I know several members here have both a Minifish and a Sunfish, and as a new member of that club, I'd love to hear how the two compare in your experience. For example, Tag, I know that you enjoy sailing with one of your sons on your Sunfish while the other son skippers the Minifish. How does your Minifish with a single occupant compare to two of you on your Sunfish? I ask because I just got my wife a '75 Minifish and we went out Sunday afternoon, with me attempting to follow her in my old 140 lb '71. I wanted to stay behind her so as to film her maiden voyage with a camera mounted to my Sunfish bow handle as she solo'd on her mini. However, I found that my heavy Sunfish continually wanted to pass her light Minifish. I was thinking that 95 lb Mini with a 120 lb occupant and a 65 sq ft sail would be fairly comparable to a 140 lb Sunfish with a 170 lb occupant and a 75 sq ft sail. But it didn't turn out that way. (Winds were 8-14 that day, so I'm wondering if things change as the wind increases). Don't laugh at the picture below. I accidentally installed the wind tell on the lower boom instead of the upper boom, which didn't help her in judging wind direction. (It has since been fixed)
 

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Weston, tbh I'm not sure I've ever tried to compare them, and I've never personally sailed the Minifish... I'm just too big for it.
I'm wondering if you tried to have the sail settings the same (gooseneck, halyard, etc) and then "raced" each other to compare boat speeds again would it change anything? I would have thought the lighter Mini would be a bit faster.
 
The Portsmouth Ratings indicate that, all things being equal, the Minifish is inherently slower than the Sunfish. The 2017 Portsmouth DPN for each species in the Sunfish family are as follows:
  • Sailfish - 118.40
  • Minifish - 113.40
  • Minifish II (AKA Super Minifish) - 103.0
  • Super Sunfish - 100.70
  • Sunfish - 99.60
A couple of things surprise me about these numbers:
  1. A Minifish is 12% slower than a Sunfish?
  2. A Minifish II with a 60 sq ft cat rigged sail is 8.8% faster than a standard Minifish that has a larger 65 sq ft lateen sail. YET... a Super Sunfish with its 65 sq ft cat rig is 1.1% slower than a standard Sunfish with its 75 sq ft lateen sail. I'm having a hard time explaining that.
However, I'm thinking that there may be certain conditions where the Minifish could sail faster than a standard Sunfish. Possibly light winds, running downwind with no daggerboard, and small waves.

The things that work against the Minifish are:
  1. Same size rudder and daggerboard as the std Sunfish. So, the power/drag ratio will be lower for the Mini
  2. Shorter boat. Generally, a longer boat is faster
  3. Smaller sail - 13% less sail area for recreational sails
The things working to the advantage for the Mini
  1. Lighter - so the power/weight ratio should be better for the Mini. Assuming a 160 lb passenger, a loaded Mini is 81% the weight of a Sunfish
  2. Faster off the line
  3. More responsive in turns
  4. Wetted surface may be less, which may help the Mini in lighter winds - in light winds where that friction is more noticeable
I'm curious what others think of this analysis.
 
I think 1 and 3 are predominant.

Just at a rough calculation, the length/cube root of displacement seems about the same - so the length shouldn't buy any speed.
 
The big reason the Sunfish has a much lower (faster) rating is the modern board and racing sail. The Super used to have a better rating than a standard due to the cat rig and somewhat improved daggerboard. But the Sunfish racing sail and composite centerboard erased that advantage. If you could find an old rating for a Sunfish with wood board and flatter sail it would be more of a fair comparison.
 
The big reason the Sunfish has a much lower (faster) rating is the modern board and racing sail. The Super used to have a better rating than a standard due to the cat rig and somewhat improved daggerboard. But the Sunfish racing sail and composite centerboard erased that advantage. If you could find an old rating for a Sunfish with wood board and flatter sail it would be more of a fair comparison.

The Sunfish with rec daggerboard and rec sail is rated at 102.8
 
The Sunfish with rec daggerboard and rec sail is rated at 102.8
Aborgman and Beldar, Thank you for your analysis. Very helpful. Based on this information, I’m guessing that my Super with its cat rig, with the plastic daggerboard and rudder should, in theory, be at least as fast as my standard Sunfish rigged with its lateen race sail.
 
What we have found is that the cut of the sail plays a significant role. And maybe your wife was letting you pass her :)
 
When Skipper sails on 1965 WAVE with the 37 year old Riviera style sail I can keep up with her, if I'm on a boat with the race cut sail that our sailmaker made for us. I think WAVE also had the Spoon tip daggerboard and I had a Barrington. The sail in your photo appears to have a little less draft in the foot than a race cut Sunfish sail. The newer Sunfish sails from Laser Performance have a nice full cut draft as well, they look droopy when you bend them on but fill out nicely in a breeze. The leech on the Mini sail seems a tiny bit flat as well, and the outhauls may have been a bit tight. Sheeting angles also come into play. Beautiful sail colors.

Does the Minifish have the Shadow board?

The longer waterline of a Sunfish is an advantage.
 
When Skipper sails on 1965 WAVE with the 37 year old Riviera style sail I can keep up with her, if I'm on a boat with the race cut sail that our sailmaker made for us. I think WAVE also had the Spoon tip daggerboard and I had a Barrington. The sail in your photo appears to have a little less draft in the foot than a race cut Sunfish sail. The newer Sunfish sails from Laser Performance have a nice full cut draft as well, they look droopy when you bend them on but fill out nicely in a breeze. The leech on the Mini sail seems a tiny bit flat as well, and the outhauls may have been a bit tight. Sheeting angles also come into play. Beautiful sail colors.

Does the Minifish have the Shadow board?

The longer waterline of a Sunfish is an advantage.
Finally responding to you 3 years later, Charlie. (I'm blaming the pandemic LOL)
Her Minfish has the shadow board. We tried sailing with my newer plastic foil, but it is unecessarily long,
 

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