Thoughts on J/22 tuning: Lose that Tension Gauge!

Article by Greg Fisher

	" We're having great success with your "tension gauge-less" tuning method. I think it really helped us. Besides consistently nailing the proper rig tension, it has the added benefit of forcing us to sail upwind before every race which gives us a better handle on the numbers and lets Jimmy get a feel for the conditions. We're definitely working harder BETWEEN races and it's paying off!" Kett Cummins, New Orleans

How hard is it blowing? How much above base are you tuned? Are you tuned for the lulls or the puffs? How much weight are you sailing with? Which gauge are you using? Where on the shroud are you checking your tension?

These are all too common questions when it comes to tuning the rig on your 22. It’s always interesting how difficult it is to come to a consensus on the proper rig tension in varying breezes…. 5 boats may have 5 different settings! One sailor’s 10 mph breeze may be another’s 15mph.

All sailmakers’ tuning guides have very detailed charts that give fairly accurate suggestions for relative numbers for setting shroud tension over the entire range of conditions but it is still difficult sometimes, to be sure with confidence, that you’re tuned for exactly the “right spot”.

Here’s a suggestion for double-checking your shroud tension for all breezes, crew weights and wave conditions. Actually Pete McChesney introduced this guide to me in between races during the Worlds in 1999…my first major regatta in the class.

Pete suggested gauging proper rig tension (or lack thereof) on the visible tension on the leeward upper shroud when sailing upwind in all conditions.

Basically, we sail upwind before the start and check the slop in our leeward upper shroud. If it is “substantionally” loose we wind up the turnbuckles on both sides equally, usually ½ to ¾ turns at a time (first the leeward side, then we tack and tighten the new leeward upper a corresponding number of turns) until the leeward upper becomes nearly taught (but not tight!). When close, a slight wiggle in the upper shroud should barely be noticeable. The “wiggle” should not be a whopping 4”…. But more a subtle ½ inch twitch. This very slight movement is helpful as it is much easier to detect when you’re too tight since there is no movement in the shroud. In addition the slightly looser rig allows for sag in the headstay when the backstay and/or mainsheet are eased which provides more power in the jib. However, too much looseness in the rig will allow the mast to overbend, the main to become too flat, headstay sag to become excessive and the jib to become too full.

It is important to set up your sails as close as possible to your normal trim before tuning. You will then set your rig tension automatically for your crew weight sailing in those waves and breeze.
Setting the lower shroud tension requires a bit more judgment but again a very basic guide simplifies the process. Once the upper shrouds are tensioned properly, the lowers are tuned so that the mast is nearly straight laterally and in column. Like the uppers, the lowers are tensioned equally on each side until the lateral mast bend is close.

To determine if the mast is close to straight (we actually look for a bit of sag to leeward in the mast at the spreaders, close to ½”) I lay my head on the windward side on the main, facing forward, looking up and sighting the luff groove/tunnel. Using the amount of deflection of the groove at the spreader bar from a straightline between the head and gooseneck gives the best point of reference. I think a little sag at the spreaders is again, a great tune for the mast in all conditions…. but it doesn’t have to be an exact science. Just remember that if the lowers are too tight the mast will be too stiff fore and aft and mast bend will be restricted. This restriction is caused by the lowers being attached to the deck well aft of the mast…they almost act like running backstays. If the lowers are too loose the mast will pump when sailing upwind and especially in heavy winds, the main will be too flat since the mast will overbend. Sometimes grabbing the windward lower and pulling on it while sighting the mast will “move” the middle of the mast, straightening it, and may help locate the point of reference and determine the amount of sag.

Once you become comfortable with this process, the tuning can go quite quickly and more accurately. We find that usually for every full turn we take on the upper, the lowers require only a ½ turn to correspond…. but we always check the slight sag on each side to be sure!

Good luck and happy tuning. Feel free to contact me if you have any questions!