Tuning your Nirvana

Some Ideas on the basic setup:

1. Place your boat on its stand indoors and make sure your mast is vertical and then adjust from there. You can measure the length of the shrouds and make sure they are equal as a starting point. 40.25 inches from the bow to the point where the shrouds attach to the mast is a good starting point for the forestay setting. Lateral misalignments are corrected with the shrouds and fore/aft misalignments with the forestay and backstay. These four standing rigging lines should be tight, but not A# tight as there are limits to the deck strength and the mast compression may push into the mast step too strongly.
2. Adjust sail camber next. I adjust to about an inch maximum distance between the foot of the sail and the boom for the jib and about an inch and a half for the main if the wind is 2-10 mph, less if it is above 10 mph.
3. At the pond, put your boat on the stand with the keel outside the frame, so that it ‘heels’ and is pointing about 45 degrees to the wind. Stand behind the boat, (this is as close as you will ever get to being on board!) and using the transmitter check for rudder and sail movement before pulling in the sails fully. Now look at the main leech, (the back side of the triangle), and make sure that it is has enough twist, that is the top of the sail is angled further away from the centerline of the boat than the lower part. This is adjusted with the vang, which pulls the boom down and reduces twist. The basic relationship is that more twist gives more power, but more ‘drag’ as speed increases. If the wind is strong enough to achieve hull speed (usually at 8-10 mph), then more twist depowers the rig, reduces heeling and helps the boat power through waves.
4. Check your mainsheet adjustment so that at full in travel the boom is on the centerline, but not being pulled down by the sheet, and at full out travel, it is just about hitting the shrouds.
5. Lastly, adjust the slot between the sails by setting the boom sheet attachment so that the jib boom has a slight positive angle to the main boom. In low winds this is a small angle, as the wind increases open up the angle and also reduce sail camber.
6. Put your boat in the water, using a gentle ‘put it in and push out’ technique, and check your ‘on the wind’ tune. If you find your boat is pointing well and sailing steadily with little rudder input, just pushing gently up into the wind after a while, then you have perfect tune for the conditions. Stay with it unless the conditions change. If, however, the boat pushes up into the wind on the gusts, or needs large rudder inputs to keep it in a straight line, then bring her back in and move the center of effort forward to balance your boat. This is most easily done on the new 2014 boats by sliding the jib pivot back on the jib boom to move the jib forward. It can also be accomplished by raking the mast forward, which is the method for earlier boats.
7. Sailing her. In high winds don’t haul in the main all the way, and ease the sheets with the puffs, watching for cats paws on the water as the gusts come towards you.
Bear away to increase boat speed before tacking and ease the sheets a little after tacking to get back up to speed, before pulling in as your speed reaches a maximum.
Luff up a little into a very strong wind if your sail servo isn’t pulling your sails in fully.
Don’t worry about pulling your boat out to make an adjustment if it needs it, but if you are doing well, leave well alone and focus on sailing what you have.
Clearly these are just starting points and you will learn with practice what can be adjusted to produce a faster, higher pointing boat.

3 thoughts on “Tuning your Nirvana

  1. I just ought a Nirvana 1 month ago. I had it out in too strong of winds. The servo arm that controls the lines for the sails stripped of the teeth inside. Now it won’t hold when I try bringing the sails in during a breeze. Anywhere that I can buy a new arm? Thanks, Charlie McGowan

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