Catsailor.com

Nacra 5.0 Rudder Bungee System question

Posted By: dannno

Nacra 5.0 Rudder Bungee System question - 06/18/12 12:28 AM

Hi all -

I have an older Nacra 5.0 with the older rudder system that uses bungee to pull the blades up when the blades are released.

I've tried all different types and diameter of bungee and cannot find one that works. If the bungee is too stretchy, the blades don't pop up when released. If the bungee is not stretchy enough, the bungee is too taught to pull the blades down while sailing.

I thought I remember someone suggesting running two bungees on each blade, that didn't work either.

Anyone have any suggestions on bunggee material to use or another solution short of changing to the newer rudder system?
Posted By: goose151

Re: Nacra 5.0 Rudder Bungee System question - 06/18/12 12:53 AM

8mm shock cord. The total length is 125% of the length of the rudder arm. ie if your arm is 710mm long you need 710*1.25= 900mm. This allows for a 45mm over lap (join).
Posted By: erice

Re: Nacra 5.0 Rudder Bungee System question - 06/18/12 04:19 AM

many off us only rely on the bungee as an emergency popup to save the transoms from being ripped out

to get an early nacra rudder all the way up and locked means fitting another jam cleat on each alloy tube and a line running from the back of the rudder, up through a split ring on the tube end and through the jam cleat
Posted By: JeffS

Re: Nacra 5.0 Rudder Bungee System question - 06/18/12 09:21 AM

Do what goose said, the only thing I can add is the brand of shockcord is important. Most shockcords sag very quickly not holding the rudder up but the brand that Nacra sells doesn't stretch and sag after you set it. Nacra sells it cut to length and it's very cheap. If you cant get proper shockcord you can make 10mm fit through the hole in the blade with a bit of effort then pull each end out the end of your tiller arm then tie a knot in one end then stretch the other out as hard as you can and tie a knot in it. The knots won't fit down the tiller arm. Definately not as pretty as doing it with the Nacra shock cord. To do it perfectly with the 8mm shockcord Nacra have stainless steel clips that you can apply with pliers that lock the bungy together. I've done both of these methods to two different Nacra 5.8's in the last 2 weeks. If no matter how hard you tighten the shockcord the rudders don't pop all the way up unless your blades are a bit sloppy in the rudder stocks, it means the top of your rudder stocks are too close together I can give you an easy fix if you have that problem, you don't want any wobble
Posted By: catman

Re: Nacra 5.0 Rudder Bungee System question - 06/18/12 04:31 PM

I would use a pull up line instead of the shockcord. That system has problems. If your rudders kick while your sailing the last thing you want to happen is to have no rudders in the water.
© 2024 Catsailor.com Forums