Abraxas Racing - Santana 525 Tuning Guide |
The following opinions are my own and do not necessarily reflect any known reality...
Mast
An excellent book is "Sail & Rig Tuning" by Ivar Dedekam. He recommends a 2 - 3 degree rake for a fractional rig, which equates to 11 - 18 inches for the 525 mast.
My mast is raked a lot. I don't have an an exact measurement between two fixed points, but I can tell you that the top of the mast is basically raked back to the "plane" directly vertical to the chain plates. This is about 16 inches. I had it raked a couple of inches more, but that was too much weather helm. 16 inches seems OK until the winds get into the 30s then the main must be eased a lot to reduce the weather helm.The rig is tight, uppers 640/650 or more and lowers 320/350 (or a lot more ... see below) using a Loos gauge. This is about 20% or more breaking strength as mentioned in the Dedekam book. The head stay is only adjusted to change the rake. Then tighten the shrouds. The mast should end up with a bit of "pre" bend in it this way. Maybe 2 inches.
If your leeward shrouds are loose in anything but the strongest winds, then your shroud tension is too low.
I don't bother much with the back stay until the wind is strong. It doesn't have the affect on the jib like a mast head rig; too much back stay will loosen the forestay rather than tightening it because the mast bends and loosens the forestay. You need running backstays to tighten the fore stay, but they are not "legal" on one design. I don't know if they can be used on PHRF without affecting the rating.
If you have your lowers tight enough, you can overcome the tendency to loosen the forestay. Very tight lowers will prevent the mast from bowing and loosening the forestay when the back stay is tightened. This allows the backstay to tighten the forestay similar to a masthead rig, but he the lowers must be very tight. This is described in the Bruce Kelley tuning guide above.
Up Wind
The boat is supposed to point really high, but I can not often point with a U-20. This is probably due to dissimilar sheeting angles since U-20s have very small headsails. A J-22 seems to me is easier to point against. I've never faced a J-24 but have raced Merit 25s and Capri 25s, and point similarly or higher. I can consistently out point the other 525s and leverage over them even from a couple of boat lengths to leeward as long as the water is pretty flat.
In winds up to 8 or 10 knots, I have the main flattened just a little for good draft shape. It's dacron. Nothing too tight. The main is sheeted to center line and the top telltale stalls about half the time. This usually puts the traveler car around the outer edge of the windward seat.
The 155 genoa is tri-radial composite. It is just tight enough to barely pull it snug in light air. Sometimes there is just a hint of droopy looseness between the tack and the bottom of the foil which is about 30 inches above the tack. I installed two sets of adjustable blocks on the inboard tracks. They are in the standard position at the edge of the combing. I keep one set all the way aft to turn the sheets back to the winches. The other set is adjusted forward and back over about a foot from the back edge of the cabin towards the stern. The car is moved forward or back to keep the sail from 2 to maybe 6 inches from the spreader. The foot is touching the shroud. Lighter air is 4 to 6, stronger is 2 to 4. If the wind gets stronger, I might actually have the foot "too tight" at the shroud, "kinking" the bottom of the sail against the shroud upward for about one foot up from the foot and bring the sail right to the spreader tip.
I keep one block at the aft end of the track to turn the sheet forward. the second car is moved forward or aft on the same track to alter the twist of the genoa. More forward brings the top of the sail in relative to the bottom, more aft lets it out more. The track I use is the stock track running back from the chain plates at the edge of the cockpit.
Keep the draft of the head sail at 40% from front by increasing halyard tension as wind increases.
Keep draft forward on main and top batten parallel with boom. By parallel to the boom I mean the back half of the top batten should be parallel to the boom. It will be down wind but pointing to the stern in the same direction as the boom. You do this by using more or less mainsheet tension depending on wind speed, and then you can pull the traveler up to put the boom on centerline.
A flatter main in very light wind is actually ok because the flow will "stick" better to the flatter shape.
Bear off if there are waves going upwind; they slow you down. Use power rather than pointing because the boat is too fat to push through the waves without losing speed.
Keep everyone ahead of the traveler. Even go so far as to remove your outboard and put on the cabin sole.
Keep the boat flat!! To keep the boat flat, use rail meat, its worth half a knot or more. Ease the main out in stronger winds if you are light on crew. Add twist to the sails to de-power the tops in heavier winds. The boat will pick up a knot or more speed with less sail area if you keep it flat. Less than 15 degrees is good less than 10 is better less than 5 yahoo..... watch that knot meter and adjust accordingly.
Down Wind
Going down wind have a person go to the bow. Watch your speed and have the person move for and aft to max speed, it lifts the stern and reduced wetted surface drag. This is good for a knot or more.
Never go dead down wind. 30 degrees or more off the wind is much faster (unless the wind is blowing like stink). If you have an instrument, use 140 degrees true in winds 10 knots or below. Then gradually go deeper as the wind speed increases.
Keep your spinnaker clews level by constantly adjusting the pole. Install the single line spinnaker pole lift as described in the owners manual. At the same time, make sure the luff edge of the spinnaker is breaking top to bottom by adjusting the pole height also. These two concepts should not be mutually exclusive.
Down Wind Without Spinnaker
I would gibe downwind at the same angles as tacking upwind when racing without a spinnaker. The main will block the genoa unless you gibe wide or go dead down wind wing and wing, but ddw is very slow due to the lack of apparent wind. Unless the wind is blowing 30mph then it would be ok to go ddw.
Some tactics books say that wing on wind directly at the downwind mark is the fastest way to sail downwind without the spinnaker.
Sails
Doyle and Ullman makes my sails. I prefer dacron mains and composite tri-radial (or if you are rich enough) a monolithic head sail. I use the 155 genoa about 90% of the time. Main sail has a reef about 2 feet up and another about 1/4 way up the sail. The main should be loose footed. A flattening reef about 8 inches or so up from the clew works better than the outhaul. My battens are about 3 feet long. The lower three are of uniform thickness, but the upper is tapered for flexibility. The roach extends a bit beyond the back stay.
For older droopy sails, you may be able to move the draft of the sail forward by tighter halyard tension, tightening the cunningham and bending the mast a little.
Odds and Ends
A clean bottom is worth keeping.
I have seen some 525 with a track about halfway between the cockpit edge and the edge of the deck. If you have one of these, I think they work best for reaching. I only use the stock tracks.
I have an outside track on the edge of the deck between the last two stanchions. This is used for the spinnaker blocks. Some boats have additional tracks forward between more stanchions.
You may be able to barber haul going down wind by either having a block well forward on the track or even attached to the base of a stanchion. (some boats have more tracks between the stanchions going towards the bow that you can use). Then you can use the forward line to decrease twist in the genoa going downwind while controlling the sail angle with the sheet. You tighten the forward line to bring the top of the genoa in more so the sail doesn't let the wind get away at the top while going down wind. I have never actual done this on my 525, but did on a Capri 30 sometimes.