1. Tuning Guide

1. Tuning Guide

SB3 Tuning Guide (nb. tips on launching further down) – Author Jerry Hill

This guide is far from being a definitive tuning guide for the SB3. What it contains is some of my own thoughts and experiences from sailing the boat for 2 years, and some tips on what I have learnt during this time.

Initial Rig Set Up

Use the Laser set up from the rigging guide as a starting point. The set up of the bottlescrews that are found above the main spreaders is crucial for ensuring the mast is set up in column, so some adjustment over time will be needed to make sure the mast is straight sideways, in conjunction with the main rig bottlescrews. Once the mast is straight athwartships, you can work on getting the correct fore and aft bend.
I set the lower shrouds that terminate at the gooseneck at about two turns tighter than hand tight. My base settings on a standard loos gauge (the larger black one with delrin rollers): Caps 38, D1’s 35.
Some owners who have tried to replicate these settings have complained that there is too much pre-bend, which at my base setting is approx. 5” maximum with no backstay on. To see the pre-bend sight up the mast with the main halyard pulled on tight to the gooseneck. If this is the case, straighten the mast a little using the D1’s and lowers.
My set up has been fairly straightforward. I work from this base setting, and then I adjust a little up and down the wind range. In light airs I ease the caps by 2 turns – this loosens the forestay, powers up the front of the jib and allows the rig to “breathe” a little when underpowered.
In medium breeze, 8kts+ when all crew are sitting on the side, the rig is returned to base setting for maximum power. As the breeze gets up to 18kts + I will start to wind some extra turns on the caps. This will bend the mast more to flatten the mainsail, and tighten the forestay. If this overbends the mast you can add a little tension to the D1. Remember what changes you make so that you can return to base at the end of the day. Ensure you carry the appropriate tools to easily adjust the rig on the water between races.