Fireball Tuning Guide

Rig Tension

Tight, measured on Jib luff wire 350/400 lbs.

Mast Rake

Medium winds:- 150-250mm

Strong winds:- 300+mm

Check with jib only hoisted. Rig tension on. Hoist tape on main halyard and measure to the top of the transom.

Jib Sheeting

With the jib pulled in tight, the continuation of the jibsheet from the fairlead to the clew should intersect the front of the jib 1900mm up the luff wire. When over powered in heavy winds move the fairlead aft to flatten the jib and open the slot between the jib and the mainsail.

Spreaders

Length measured from the shroud to the side of the mast.

Check sweep back of spreaders by placing a straight batten from the port spreader tip to the starboard one. Measure from the centre of the batten to the rear of the mast.

To make the mainsail fuller swing the spreaders forward. To flatten the mainsail swing the spreaders aft.

Prebend

Check with jib only hoisted and the rig tension on.
Measure to a straight line between masthead and the black band at the gooseneck

Straight rigs , Epsilon, M2 - 25mm
Prebent rigs, Stratos, M7, D - 35mm

Deck Level Control

With the boat rigged as for pre-bend check, lock the mast at this position. Allow the mast to go forwards 5-10mm in very windy conditions.

Spinnaker Pole Height

Check by hoisting a tape measure on the spinnaker halyard and measuring to the outer end of the spinnaker pole. Use 3800mm for reaching. For running in strong winds raise the pole, and for light winds lower the pole.

Class website http://www.fireball-dinghy.org.uk