North Sails RESOURCES
Mirror Tuning Guide
- Last Updated: June 14, 2022
Is measured from the top of the mast/gaff to the centre top of the transom.
Wooden Hulls – 4950mm – 5000mm (These measurements work for both Gaff and Bermudan
Goodwin hulls – 4975 – 4850mm
Winder Hulls – 5000mm – 5100mm
12 to 16 on the shrouds using a Loos tension gauge for older boats. New boats both wood and frp will take 18-22.
This isn’t as critical as it would be if the mast had spreaders, however it still controls the amount
of jib luff sag and mast rake so care should be taken to keep a record of your setting so it is the
same every time.
Upwind, set the outhaul so that the foot just touches the leeward side of the boom. If the conditions are choppy and you are not overpowered ease the outhaul so that there are 2cm between the leeward side of the boom and the foot. In strong winds pull the outhaul tight. Downwind, you can ease the outhaul 5cm if you want more power.
Fairleads and Jib Height
The fairleads should be positioned as far back as possible on the thwart and as high as possible.You are allowed to fix the fairlead on a block 25mm high. The distance between the bearing surfaces of the fairleads should be roughly 750mm.
Start with the tack corner of the jib 30mm above the deck.
Raise it to 50mm above deck for light and moderate wind and waves.
Lower the tack corner to level with the deck for strong winds.
Pull it down 10 – 20mm below deck level for very strong winds.
Kicker and Twist
I think twist is the key to making a Mirror fast. A closed mainsail leech will make you point but if you overdo it the sail stalls, the boats slows, and you go sideways, giving the same effect as not
pointing. Keep leeches open enough to stop the telltales stalling. This isn’t so much of a problem
once you are both hiking because there is pressure on the mainsail leech to keep it open, but it is
still possible to oversheet the jib. If the boat slows down compared to the boats around you or the
boat feels as though its bouncing up and down on the spot, ease the jib sheet 1cm and see if
Marks on the jib sheets are very helpful here and even calibration marks on the kicker will help
you re-produce your fast settings.