K6 TUNING
David Hitchcock and Ian Nicholson won 5 races at this years championship and are long time class experts. Here David offers some advice and observations on the new class sails from North.
Overall the North’s offer speed and pointing improvement over the Hyde sails but only if properly trimmed for the conditions. Adjustments to the Hydes had far less affect than on the North’s so were in many ways more user friendly.
Jib
The flatter entry means that the forestay, luff and sheet tension are all important.
We set the luff tension so that creases were just visible throughout the wind range.
The forestay (adjusted by rig tension) worked best with some sag to create more depth in the luff/entry particularly in the lighter, choppy conditions.
The sheet tension seemed to be best when not tight in unless 20kts+
Jib car position inner position now in as far as 200mm (from 150mm in the tuning guide) in 5-10kts (flat water) then progressively outboard to prevent back winding of the main.
Clew board – use middle hole in all conditions. That said if all other controls are set up correctly, we used the next hole up in 5-10kts for more leech tension which worked well but is much more tweaky to keep that top leech tell-tale streaming!
Make sure that the leech line isn’t over tight and curling the leech. Adjust so that the leech is only just not flapping.
Many people commented to me that the jib was really difficult to use – this is almost certainly a product of having too much rig tension and/or luff tension.
Main
The number one rule here is to keep it sheeted in to the centre line at all times going up wind. We managed this in the complete wind range even up to the shroud breaking 25kts day! Obviously this is to some extent weight dependent so for the record we weigh in at about 185KG
Outhaul – 0 to 5kts tight : 5-15kts : eased with 50-75mm depth from boom at the midpoint. 15-20Kts : 25-50mm at midpoint. 20kts+ : tight
Cunningham – tighten to assist de powering as need. We didn’t use it at all until wind 15kts+
Vang – the sail has much less luff curve than the Hyde so needs much less vang. I preferred to keep the main in the middle with minimal vang tension and use the mainsheet to control the leech/bend. This appears to enable the main to stay central to maintain pointing and keep the bottom third of the sail driving. Lots of people complaining about starvation creases which are a product of too much vang and/or lowers too slack. In my view whilst the sail could do with a tad more luff curve to make a bit more user friendly its fine (and quicker)as it is. People just need to learn how to control the rig, vang and mainsheet tension.
Rake/Spreaders
The numbers on the tuning guide for the Hydes are still good except perhaps slightly tighter lowers in the 5-15kts range.
Rake measured from mast tip to transom /hull join
Tensions measured with Loos gauge on the shore with no mainsail up
Overall the North’s offer speed and pointing improvement over the Hyde sails but only if properly trimmed for the conditions. Adjustments to the Hydes had far less affect than on the North’s so were in many ways more user friendly.
Jib
The flatter entry means that the forestay, luff and sheet tension are all important.
We set the luff tension so that creases were just visible throughout the wind range.
The forestay (adjusted by rig tension) worked best with some sag to create more depth in the luff/entry particularly in the lighter, choppy conditions.
The sheet tension seemed to be best when not tight in unless 20kts+
Jib car position inner position now in as far as 200mm (from 150mm in the tuning guide) in 5-10kts (flat water) then progressively outboard to prevent back winding of the main.
Clew board – use middle hole in all conditions. That said if all other controls are set up correctly, we used the next hole up in 5-10kts for more leech tension which worked well but is much more tweaky to keep that top leech tell-tale streaming!
Make sure that the leech line isn’t over tight and curling the leech. Adjust so that the leech is only just not flapping.
Many people commented to me that the jib was really difficult to use – this is almost certainly a product of having too much rig tension and/or luff tension.
Main
The number one rule here is to keep it sheeted in to the centre line at all times going up wind. We managed this in the complete wind range even up to the shroud breaking 25kts day! Obviously this is to some extent weight dependent so for the record we weigh in at about 185KG
Outhaul – 0 to 5kts tight : 5-15kts : eased with 50-75mm depth from boom at the midpoint. 15-20Kts : 25-50mm at midpoint. 20kts+ : tight
Cunningham – tighten to assist de powering as need. We didn’t use it at all until wind 15kts+
Vang – the sail has much less luff curve than the Hyde so needs much less vang. I preferred to keep the main in the middle with minimal vang tension and use the mainsheet to control the leech/bend. This appears to enable the main to stay central to maintain pointing and keep the bottom third of the sail driving. Lots of people complaining about starvation creases which are a product of too much vang and/or lowers too slack. In my view whilst the sail could do with a tad more luff curve to make a bit more user friendly its fine (and quicker)as it is. People just need to learn how to control the rig, vang and mainsheet tension.
Rake/Spreaders
The numbers on the tuning guide for the Hydes are still good except perhaps slightly tighter lowers in the 5-15kts range.
| 1-5 knots | 5-8 knots | 8-12 knots | 12-15 knots | 15-18 knots | 18-22 knots | 22+ knots | ||
| Shroud Tension Up wind |
15 | 20 | 25 | 25 | 25 | 25 | 22 | Never |
| Shroud tension Downwind | 15 | 25 | 31 | 32 | 33 | 35 | 35+ | Let |
| Lowers Tension Upwind | Fully Slack | Just Slack | Just Slack | Just Slack | Just Slack | Just Slack | Just Slack | Forestay |
| Lowers Tension Downwind | 7 | 10 | Go | |||||
| Rake Upwind | 8670 | 8670 | 8670 | 8600 | 8600 | 8600 or less (1 full hole down on shroud plate) | 8600 or less (1-2 full holes down on shroud plate) | Slack |
| Rake Downwind | 8660 | 8660 | 8660 | 8650 | 8650 | 8650 | 8650 | downwind |
| Spreader deflection | 235 | >235 | 235 | 235 | 235 | 235 | 235 | |
| Spreader Length | 480 | 480 | 480 | 480 | 480 | 480 | 480 | |
| Kicker | loose | Just tight | tight | tight | Very tight | max | max | Up to 15 kts aim is to get the top telltale on the mainsail to be just stalling |
| Cunningham | off | off | off | Just remove luff creases | Just remove luff creases | tighter | max | |
| Outhaul | tight | Ease so foot not creased | Ease so foot not creased | tight | tight | tight | tight | |
| Jib Car | 150mm | 150mm | 150mm | 150mm | 100mm | 50mm | End stop | |
| Jib Clew | Middle hole or top hole in flat water | Middle hole or top hole in flat water | Middle hole | Middle hole | Middle hole | Bottom hole | Bottom hole | Jib sheet tension – ensure that top and bottom telltales break evenly. In 15kts+ always ease in gusts |
| Mainsheet | Centre | Centre | Centre | Centre | Ease | in | Gusts | |
| Mast deck puller | slack | Just tight | Tight – mast straight to spreader | Tight – mast straight up to spreader | Tight – mast straight up to spreader | ease | ease | Note – better to keep more tension on the puller and use more kicker to bend the mast |
Rake measured from mast tip to transom /hull join
Tensions measured with Loos gauge on the shore with no mainsail up