Scuttlebutt Posted October 27, 2012 Report Share Posted October 27, 2012 Well 3 races down and the jury is out 15-18 knots New sq top won 8-10 knots the Pin head won score Square top 1- Pin Head 2 Still a lot of sailing to go!!!! Link to comment Share on other sites More sharing options...
humungus2 Posted October 27, 2012 Report Share Posted October 27, 2012 so is there any rule about fitting a mast spanner. Link to comment Share on other sites More sharing options...
Scuttlebutt Posted October 27, 2012 Author Report Share Posted October 27, 2012 I have no Idea if that is class legal but we should get a ruleing from NACRA prior to Nats. How about it NACRA is a mast rotation control class legal? I noticed that there is a leach line on the new sails. What are the thoughts about when and how to use it??? Can we measure in 2 sails at the Nat measureing then choose one to race with?? Link to comment Share on other sites More sharing options...
knobblyoldjimbo Posted October 28, 2012 Report Share Posted October 28, 2012 Sounds to me somewhat illogical. Additional area up top would be more effective in lighter air, in more pressure the top would be falling off anyway or causing healing moment rather than forward speed. There's no way that a sq top main would be able to hold leech tension in higher breeze so it would have to fall away. More power in the lower part of the main would have to be more effective in bigger pressure. Sounds more like skipper differences, one more capable in light with any sail. Even if the skipper is the same person. KO Link to comment Share on other sites More sharing options...
Scuttlebutt Posted October 28, 2012 Author Report Share Posted October 28, 2012 My body weight is better suited to lighter breezes but Andrew and I are very evenly matched over the last 2 seasons with almost tit for tat wins. so I believe that we are seeing a small amount of skipper difference and a small amount of sail difference as well. His boat speed to weather in the light was definatly slower than his sail from last season but his down wind speed seemed a little more competive than last season in similar conditions. Link to comment Share on other sites More sharing options...
Leadfoot Posted October 30, 2012 Report Share Posted October 30, 2012 There should be no problem with mast spanner reversing. The precedent has been set with rosco sailing a Nationals (and states I think) with the mast spanner reversed on RED HOT & COOL. As it is the standard nacra 16 has mast rotation controls though not very useful for upwind. How have you found the ability to control the leech in stronger winds. Rumor has it Corey has been trialling a boom to get better control of said leech. Have you tried the Taipan/ aclass spreader ideas with it raked back a bit more and bucket loads more tension. Don't know how that will react with the Nacra tree trunk. On the glass half full side of it though it looks like both sails will be competetive at the nationals. Link to comment Share on other sites More sharing options...
Scuttlebutt Posted October 30, 2012 Author Report Share Posted October 30, 2012 Still early Days for Andrew as far as changing things go. It is very difficult to set our masts up for pre bend because the turnbuckles supplied with the boat simply are not strong enough, you strip the thread on the turnbuckles if you try, Also the shape of our mast is not as elongated as the other masts and react very differently to pre bend. I played a lot with pre bend with the Pin head, I replaced the turnnbuckles and was able to pre bend the mast. I got several advantages when i pre bended the mast. the first was when I taked with luff fully on the mast just rotated all on it's own as it was bending for and aft more as well as sideways. This made my tacks much quicker in a blow. I found that in certain conditions I was very quick ( moderate). In light to moderate I definatley did not go as quickly as when I sailed the boat with no pre bend. Also the existing sails had been developed to suit the sideways mast bend not the fore and aft bend. Eventually I have gone back to sideways bend with these masts because I am more consistant in boat speed with it.. It seems to me that we need to get the leach to stand up longer. Can that be achieved by using the Leach line or by using softer battens? Also if we use less rotation will that make the leach hold up longer or will it make it drop off sooner? Link to comment Share on other sites More sharing options...
humungus2 Posted November 3, 2012 Report Share Posted November 3, 2012 Good questions. Fcked if I know the answers. I am turning the spanner around today and running the new sail up the mast. Link to comment Share on other sites More sharing options...
Coremeister 2 Posted November 4, 2012 Report Share Posted November 4, 2012 There must be a rumour trail that I haven’t come across, I am not trying a boom on my boat as the new sail has been setup with the standard type of outhaul from the dacron sail, the very first prototype that was used on Doggies boat is the only one that has used a boom, all subsequent prototypes and production sails have the standard outhaul setup, my boat has this setup, Matthew you would have seen this setup at the Humpybash in September, due to work I have only managed to sail once since then. Doggie and I went out to try a few things in late September from Humpybong, I still have my spanner turned around but am yet to be convinced that it will provide any advantage, have only managed to sail in light and moderate conditions so far so will reserve my judgement until I have a chance to try it in a blow. As for the class rules on the mast spanner, the class rules can be found at http://www.nacra.asn.au/site/yachting/nacra/downloads/Class%20Rules/Nacra%20Australia%20Class%20Rules.pdf rule 4.2 states that only Nacras with a boom cannot change the spanner setup, maybe to be sure someone would like to contact the National Association for clarification prior to the Nationals. Pre bending of the 16 sq mast has been tried a few times before, over the years we have tried this a few times with different sails and rig setups, most of the time it has not proved beneficial, while trying the prototypes for the new square top on my boat I tried it again and sailed in about 15 knots, I found that it makes the boat feel chocked and non responsive, returning the mast to the normal setup on the same day made the boat more responsive. If anyone wants to have a go at it with the new sail I would love to hear what you find, Mark as you have tried it previously maybe you would like to try it with the new sail (have you ordered one yet?) The only change I have made to my rig so far is to rake the spreaders back to 50mm (this is about 10mm more than I previously had), so far this seems to be an improvement but will reserve judgment until I have a chance to try it in a few different conditions (would have made this decision a bit easier with the old boat #29 as it had fixed straight through spreaders). The next thing I was going to try was a little more mast rake, this may help the uphill speed with a small sacrifice in downwind speed. I have noticed that my boat has got a little more weather helm with the new sail so the extra mast rake may reduce this, not sure until I try it. Has anyone else had much of a chance to try any ideas with the new sail, would be interested in anyone's ideas about batten shape particularly in the upper parts of the sail with regards to increasing power and decreasing power to suit various wind strengths, I know the A class guys regularly change battens in the top section of their sails, have seen the top guys drop their sails between races to change battens (they manage to do it on the water but I think this would be a bit of a struggle with the Nacra halyard system). Looking forward to anyone’s comments or ideas. Corey Link to comment Share on other sites More sharing options...
Leadfoot Posted November 8, 2012 Report Share Posted November 8, 2012 My apologies Corey. Can't remember who mentioned it. One thing I have noticed is that Brian Bedford recieved his new main last Saturday and it does not have the leech line. Don't know whether they forgot to put it on or they have scrapped it. Anyone else have a square top without the leech line. Brian commented that it was very fast to windward when in the groove but the groove is small Link to comment Share on other sites More sharing options...
nacra-maricat australia Posted November 8, 2012 Report Share Posted November 8, 2012 My apologies Corey. Can't remember who mentioned it. One thing I have noticed is that Brian Bedford recieved his new main last Saturday and it does not have the leech line. Don't know whether they forgot to put it on or they have scrapped it. Anyone else have a square top without the leech line. Brian commented that it was very fast to windward when in the groove but the groove is small The sail should have the leech line,we will getitng the sail back and fixing it for him. We are very happy with the new sail with its speed,if it is as qucik as the old sail already then in time can only get better. Remember the other sail has been used for 20 years and everybody has worked out how to make them go.I know using square tops on the Infusion it took us awhile to learn how to use them,but definately allot easier to sail with in higher winds which is what we were after and it looks great.! Link to comment Share on other sites More sharing options...
Scuttlebutt Posted November 8, 2012 Author Report Share Posted November 8, 2012 So back to my origonal question. any ideas on when to use the leach line? is it something you would adjust all the time or set it up and forget about it?? Link to comment Share on other sites More sharing options...
tonyquoll Posted November 8, 2012 Report Share Posted November 8, 2012 Hi, Saw some unanswered questions here, so am attempting an answer. I'm assuming that we're talking about the Nacra 16 square, cat-rigged (no jib). I've not sailed one of these, but have spent some time helping with sailing and tuning a Nacra 14square, which appears similar. ____________________________________________ Q: "any rule about fitting a mast spanner" The class descriptions seen at http://www.nacra.com.au/one-man/nacra-16sq Includes reference to "Mast rotation controls", so this must include a spanner. The class rules found at: http://www.nacra.asn.au/site/yachting/nacra/downloads/Class%20Rules/Nacra%20Australia%20Class%20Rules.pdf say: "For any NACRA fitted with a boom, the gooseneck and mast rotation spanner position may not be altered." As the 16sq has no boom, there seems to be no prohibition on altering the spanner. As said above, it would be better to get a ruling from the Class Measurer on this issue. _________________________________________________________________________ Q: "leach line on the new sails. What are the thoughts about when and how to use it?" When the leechline is pulled tight, it mostly adds fullness to the top part of the sail, and can help the leech stay upright. Typically you would yank this on and flick the ouhaul loose as you round the top mark, going from upwind to reach. You flick the leech loose and yank outhaul back on as you round the bottom mark and go to windward. In strong winds, you won't need more power so dont use it at all. ______________________________________________________________ Q: "It seems to me that we need to get the leach to stand up longer. Can that be achieved by using the Leach line or by using softer battens?" The most important controls for sail twist / leech tension are the mainsheet and traveler. In stronger winds, let the traveler out further and pull the mainsheet even harder. You want to keep the sail tight and ease it only in peak gusts. If you find you've got it eased most of the time to depower, then drop traveler out further and sheet in harder again. If the wind eases, so that the sail is flowing and you do don't need to ease it in gusts, then pull the traveler back up a bit. Extract from Paper Tiger Tuning Manual (1997), Chapter on Reaching by Garry Williams: "The sail needs to be cut with sufficient seam shape to lock the sail shape into place to gain maximum speed, or for the battens to be strong enough to keep the extra shape due to luff round in place. Some sailors have even been using leech cords to hold the leech up and combine that with battens that are firm on the rear section to give a similar effect." On PTs, we let the boom out past the side of the boat on reaches, and is that is beyond the end of the traveler, we cannot use the mainsheet to control leach tension out there. Garry's comments suggest that stiffer battens at top of the sail will help the leech stand up. ____________________________________________________________________________ Q: "more weather helm with the new sail so the extra mast rake may reduce this" Other way around: more rake = more weather helm. Rake moves the sail's centre of effort aft, further behind the centreboard/hull centre of effort and therefore increasing the tendency to round up to windwards. Mast rake and weather helm are generally good things to have on a cat: - mast rake provides vertical lift (like a sailboard), which increases speed and helps stop nosediving. Only on square downwind runs there might some loss of speed due to reduced sail area square to the wind. - weather helm means your rudders are generating force to windwards, which helps pointing ability. If this is extreme force on the tiller, then a separate problem is occurring; rudder rake. Use wedges between the rudder pintles and transom to tuck the tips of the rudders further under the boat, until the steering feels neutral. Be careful not to go too far, because then the rudders will pull into turns and led to loss of control, potential snapping blades. Link to comment Share on other sites More sharing options...
humungus2 Posted November 25, 2012 Report Share Posted November 25, 2012 Hows the score over there. Link to comment Share on other sites More sharing options...
Scuttlebutt Posted November 25, 2012 Author Report Share Posted November 25, 2012 2 Heavy weather races last weekend. score now 4 to Pin Head, 1 to Square top. Square top definatly quicker off the breeze. Link to comment Share on other sites More sharing options...
Leadfoot Posted November 28, 2012 Report Share Posted November 28, 2012 Four 16's raced in Bundy on the weekend. 5-8knots square head first and fourth. Results pretty much went the way we would have expected it to go if all four raced with pintop's Link to comment Share on other sites More sharing options...
humungus2 Posted December 1, 2012 Report Share Posted December 1, 2012 Sounds like it comes down to the sailor. I will find out tomorrow. Link to comment Share on other sites More sharing options...
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