Trailing edge rudder

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NED1417
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Trailing edge rudder

Inlägg av NED1417 »

Hi there,
I`m working on my rudder to sanding it and looking for the minimum thickness of the trailing edge.
I see on a drawing from 2010 (or so) that it must be 10mm but I thought that I ever saw 4mm
So, what is the right number in 2021???
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maja
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Re: Trailing edge rudder

Inlägg av maja »

See class rules and class rule drawings published on the website.(E.2.6 (a).
The thickness of the submerged part of the rudder foil shall be minimum 10 mm and the radius shall be minimum 5 mm.
Cut out a template from a sheet of plastic or similar to control the limits.
Marek, IF-båt SWE-829 "Ingela" från Lagunen i Malmö
Medlem i IF-båtförbundet sedan 1985
IF-båtägare sedan 1983
NED1417
Inlägg: 41
Blev medlem: 24 apr 2017 13:03

Re: Trailing edge rudder

Inlägg av NED1417 »

Thanks, I had the plan to make this sharp and narrow but is not allowed.
Other question;
Is it allowed to make a rudder yourself as long it's conforming to the rules?
I can make it from wood or plywood (any kind) or even foam(?) and give it some layers of polyester with roving
Or must it be built by a certified supplier?
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maja
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Re: Trailing edge rudder

Inlägg av maja »

You may make your own rudder blade and steering stick. You may use moulds or plast it around a shaped peice of wood or similar. You may use glass fibre, plastic, wood, metal and foam. The foil must not have any empty hollows.
Minimum weight wiithout fittings and plates should be minimum 22 kg (if I remember correctly).

Se class rules and drawing for further details.

My own rudder has the weight of somewhat 24-25 kg.

A rudder which is not original Marieholm is to be certified by a measurer in similar way that for sails. There is a measurement form for this.
Marek, IF-båt SWE-829 "Ingela" från Lagunen i Malmö
Medlem i IF-båtförbundet sedan 1985
IF-båtägare sedan 1983
NED1417
Inlägg: 41
Blev medlem: 24 apr 2017 13:03

Re: Trailing edge rudder

Inlägg av NED1417 »

Okay, thanks again
It's clear to me.
I found the measurement forms for the rudder and sails as well on the site.
We don,t have an official One design class and measurer (yet), do we choose one of the members?
Or have to wait when we come to Sweden?
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johan swe-1870
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Re: Trailing edge rudder

Inlägg av johan swe-1870 »

I think any national measurer certified by your national authority will do.
Johan Winberg, SWE 1870 InFinit
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