Laser 13 rig settings |
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423zero ![]() Really should get out more ![]() Joined: 08 Jan 15 Location: United Kingdom Online Status: Offline Posts: 3419 |
![]() ![]() ![]() ![]() Posted: 13 Apr 22 at 12:20pm |
Should have gone for stripes and a matt black foredeck
![]() Edited by 423zero - 13 Apr 22 at 7:14pm |
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Robert
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Sam.Spoons ![]() Really should get out more ![]() Joined: 07 Mar 12 Location: Manchester UK Online Status: Offline Posts: 3400 |
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More likely that a 'swept back' rudder blade would look racier in the eyes of a non sailor.
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Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish" |
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423zero ![]() Really should get out more ![]() Joined: 08 Jan 15 Location: United Kingdom Online Status: Offline Posts: 3419 |
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Probably already had the rudder from another boat. Not forgetting he didn't design it to be the racer it became, designed to carry two people and was going to be called the Weekender.
Edited by 423zero - 13 Apr 22 at 6:06am |
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Robert
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Oatsandbeans ![]() Far too distracted from work ![]() Joined: 19 Sep 05 Location: United Kingdom Online Status: Offline Posts: 382 |
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Yes -I am sure that’s why Bruce did it-(can’t think of any other good reason for it!)
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Gordon 1430 ![]() Far too distracted from work ![]() Joined: 27 Jun 17 Location: Lee on Solent Online Status: Offline Posts: 310 |
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The angled rudder on the laser helps no end with rowing in the starting area.
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Gordon
Phantom 1430 |
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I’ve done quite a bit of research and analysis on this. As a first approximation, to minimise drag you want the lift to be shared between the daggerboard and rudder in proportion to the square of their spans. For example if the daggerboard is 1m deep and the rudder is 0.7m deep: 1^2 = 1, 0.7^2 = 0.49, so ratio ~ 2:1 (i.e. the rudder should take one third of the total load). In reality the rudder is surface piercing and in the wash of the daggerboard so the relationship changes a little. In this example, if the rudder is less than one the total foil area then it can only provide one third the total force if angle of attack on the rudder is increased by pulling the tiller towards you. The boat therefore needs to be set up with some weather helm to keep it tracking straight.
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Oatsandbeans ![]() Far too distracted from work ![]() Joined: 19 Sep 05 Location: United Kingdom Online Status: Offline Posts: 382 |
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I remember a story about the first IACC America’s Cup. Before race 1between America cubed, and Il Moro de Venezia they both had to remove the skirts to show the world the underwater appendages. When the US designers saw the size of the Italian rudder they realised that one of the designers had got it wrong. The Italian rudder was double the area of the US one. The larger rudder was slow and draggy. The US boat was faster but the sail trimmers had a big input into what the boat was doing-. It is the same for dinghies. |
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Grumpycat ![]() Far too distracted from work ![]() Joined: 29 Sep 20 Online Status: Offline Posts: 497 |
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So true .
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Grumpycat ![]() Far too distracted from work ![]() Joined: 29 Sep 20 Online Status: Offline Posts: 497 |
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The option of a larger/better rudder was put to a class vote sometime in the in late 80s/early 90s ( back when I was a class member ) . It failed and I don’t think this option has been put to the class since .
Edited by Grumpycat - 11 Apr 22 at 10:49pm |
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Sam.Spoons ![]() Really should get out more ![]() Joined: 07 Mar 12 Location: Manchester UK Online Status: Offline Posts: 3400 |
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Actually just allowing the blade angle to be free would be a virtually no cost mod that would improver the feel of the boat immeasurably.
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Spice 346 "Flat Broke"
Blaze 671 "supersonic soap dish" |
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