The simple truth about rig tuning
There is no single "right" shroud tension setting for the H23. Even on the same boat, the "right" tension can change from day to day, depending on wind speed, number of crew, how hard the boat is being sailed and how fanatical the skipper might be.That being said, there is only ONE sure way to tell if the rig is properly tuned, It's so simple you don't need the gauge. Just sail close-hauled with full main and headsail in 12 to 15 kt of wind and watch the leeward shrouds. If they go slack, add shroud tension on both sides. Sail some more and check the shrouds again. Repeat until the lee shrouds stay taut. It's that simple.That doesn't mean the Loos gauge isn't useful. You need it to set the 20% of wire breaking strength you noted, which is about halfway through the rig tning process. Check your shroud diameter too, The 1x19 wire shrouds on the H23 have a breaking strength of 3300 lb, 20% of which would be about 650 lb.To set the rig properly, you should know what each piece of standing rigging does. The forestay is obvious. The shrouds support the mast laterally, but because of the swept-back spreaders and the shroud chainplates mounted aft of the mast base, they do a bit more on the H23 than on a "regular" boat.The uppers, in conjunction with the forestay, support the mast like the guy wires on a radio tower. They also bend the mast like a bow (known as "prebend"). Mast prebend flattens the middle of the sail and opens the leech. These are very effective ways to depower the sail in higher winds.The lowers help support the mast too, but they also stiffen the middle of the mast and reduce its tendency to bow forward, In that sense, the uppers and lowers work against each other, but that's a good thing. The backstay bends the mast like the uppers do, only more effectively.One more thing. The lowers won't be loaded as much as the uppers (about 500 lb usually) and the forestay will be substantially higher (about 900 lb but only until you raise the headsail, at which point the jib halyard and luff wire will take some of the load off the forestay.Start by slackening all the shrouds and the backstay. Tighten the forestay until you have the amount of rake you need (most people seem to think 6" to a foot is about right. Check by hanging a weight just off the deck using the main halyard and measuring from the halyard to the back of the mast near the base.Tighten the uppers until the mast has about an inch or so of prebend (eyeball up the mast track). All H23 masts will bend , but the bendy Z-Spar mast (tapered at the top) is the easiest. Make sure the mast stays vertical side to side. Now tighten each lower to about 500 lb. This prevents further prebend. Now tighten the uppers until the leewards stay tight when sailing (increase in half-turn increments of the turnbuckle as needed until you're done.That's the basic setup. On windier days you may need more upper shroud tension and more backstay tension...or you can reef earlier. Hadsail size (say 110 vs. 150) and jib halyard tension make a difference as does your personal sailing style (racing with crew? racing singlehanded? cruising leisurely with female crew that doesn't like to heel? daysailing?) That's why I said that there's no single "right" rig tension. Sorry this got so long, but I think you'll find it helpful. Happy sailing.PeterH23 "Raven"