Coremeister 2

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About Coremeister 2

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core_pfieldgroups_99

  • Location Brisbane , Qld, Austraila
  • Interests all things sailing
  • Occupation Workaholic
  • Class of Catamaran Nacra
  1. 16sq mast rotation controls advice.

    If your talking about the angle of the dangle you have to be careful as it changes when you get older, with your recent birthday moving you into the Seniors category you will need to make allowance for the increased angle of the dangle.   The other thing to consider is that if you are wondering when to stop pulling (whether there is rope involved or not) you have probably already gone to far and may be risking personal injury and even long term scaring.     
  2. 16sq mast rotation controls advice.

    Attached are the pics I was looking for over the weekend, this should make it a bit clearer These pics are of my boat with the standard mast rotator setup, disregard the extra swivel cleat and larger stand up block as these are for a spinnaker halyard setup.  In these pics it is rigged as 1:1 with the rope terminating at the spanner, then through the block then the cleat and looping around to become the setup on the other side. The one titled DSCF3293 is about the angle you would see it at going upwind The one titled DSCF3295 shows it cleated around for running downwind DSF3296 and DSCF33007 show the setup looping around to cross back to the other side, I use a small block which is attached to the inner beam strap to run the rope through, thois makes sure that it runs easily and also means you can lock it around from further back on the boat if needed. The one tilted standard setup 1 is my boat with a dacron sail, this pic was more for the detail of the standard downhaul but you can see the rotation setup as well, the one titled alternative setup 1 is Guy's boat which shows the 5.8 style downhaul that some of the boats used, this pic also shows the mast rotation rigged as 2:1 as detailed in the previous post. Hope this clears it up a bit. Regards Corey    
  3. 16sq mast rotation controls advice.

    The standard setup for a forward facing mast rotator on a 16sq is rigged as per your sketch A-B-C, there are a couple of minor variations to this, most people tie the rope end to the base of the upstand block that is on the beam at B then loop through the rotator at A (dont worry about using a block here as it only gets in the way and the rope passes smoothly over the round material of the rotator anyway, this will give a simple 2:1 system that is easier to uncleat). Then back through the block at B to the cleat on the beam at C. Again a common variation is to then continue the same rope back across the trampoline (under the toe strap) to then become the system on the starboard side, make sure you leave a bit of slack in the system as you dont want it to have to run through the system each time you tack or gybe as it will get caught and cause grief.  As per your sketch above the sail and mast shown as incorrect is actually correct, the mast rotator generally does nothing when going to windward and is only used when running downwind to over rotate the mast, this seems a little odd at first when compared to boats such as A Classes, Taipans or even F18's and F16's  (or any others with a wing profile mast and boom) the Nacra mast is more of an elliptical profile a behaves a little differently. The mast rotation when going upwind responds more to the position of the outhaul car, it will find its own angle based mostly on this and the shape and tension of the bottom battens. When running downwind the mast is over rotated  and cleated on the windward side, with the outhaul car released to the end of its track, this has the effect of adding draft to the sail which helps to run deeper, some people don't bother with running the rope but still keep the rotator in place to allow you to "pop" the sail in light winds, they can still over rotate the mast downwind by putting their knee against it to hold it there, when there is enough breeze to warrant not sitting near the front beam they simply don't worry about it, I prefer to still keep it cleated even in these conditions as it stops the mast pumping from the boats motion in waves.  The sketch you show as correct is correct by the text books and will deal with things such as maintaining attached laminar flows and angle of attack, this is critical on boats such as A's and F18 that carry wing masts, even more critical on things such as Americas Cup boats with solid wing mast/sail setups, it does not directly carry over to the Nacra system, we have played around with the ideas with both the dacron sail and the newer square tops, up until mid way through the last nationals I had my mast rotator facing backwards and rigged to allow mast rotation control upwind but still allow over rotation downwind, at previous Nationals one of the WA boats has played around with a modified system similar to that used on the F18 Infusions (I think Andrew has gone back to the normal setup). I was finding that by de-rotating the mast upwind the boat would foot off with good speed but would not maintain height to windward, and when the breeze was up and I had plenty of downhaul on the mast would flick towards the center and tend to stay there, this would really kill the height and the only way to get it to go back was to drop the downhaul and rotation control and start the process again which was not fast compared to the fleet. On the lay day i put the mast rotation back to facing forward so that I could lock the mast around slightly over rotated going to windward to stop it centering, my boat seems to do this more on on tack than the other, haven't figured out why as yet. As stated in earlier posts, over the years plenty of people have played around with various systems to control mast rotation, some are successful in some conditions and others make very little difference over the entire wind range, because of this most people end up going back to the standard system which works well over the entire wind range. The mast rotation makes the most difference when running downwind and as such it is more important to have a system that allows you to over rotate when running down wind.  If you feel inclined to play around with any ideas with your boat please keep us updated as to the success, if Andrew has any pics of his modified F18 system that would be a good starting point as it did look kind of cool and also functional but may mean you need to have and additional eyelet fitted to your trampoline. If I can be of further help just let me know.     Corey       
  4. 16sq mast rotation controls advice.

    I will try to find a couple of pics of the standard setups. As in the previous posts there have been a few minor variations over the year's, not acounting for non standard setups that tend to show up on older boats. What sail number is your boat ? I will get some time over the weekend to answer in a bit of detail   Corey
  5. 16sq mast rotation controls advice.

    Yep, still about (from time to time) may be able to help answer your questions.     Coremeister
  6. 18 sq

    Now that would have to be the "Coolest" thing on the Lake, where do you sign up for a go on that. I guess you have the spinnaker kit on order.
  7. canvas covers

    Talk to Ben at Quantum Sails in Brisbane 3393 9111. When they were Sail Tech they made quite a few fitted boat covers for many of the 16 sq's in QLD, they fit beautifully, look great and last forever, the one on my boat was made in 2007 and is still going strong, my old boat lived outside with this cover on for 4 years and my newer boat now lives under a carport but I still put this cover on to keep it clean during the extended periods of non use.  Although they are custom made and fitted they are still really good value and because Ben has the correct profiles for the cover he should be able to make one and ship it to you.   If you do use the cheaper blue poly tarps they will disintegrate quickly with the UV and leave horrible blue crap all over the boat, silver tarps will last longer but are more expensive and by the time you buy one big enough to cover the whole boat you will have made quite an investment in a short term option, plus they flap around if they are not tied on well.    Best of Luck.
  8. Looking for a 16sq sail

    I have a spare sail that is in reasonable condition. Im going for a sail later today so I will take a pic of it. I'm in Brisbane so would need to find a way of getting it to Sydney. The sail is the orginal one that came with the boat, number 273, I have only used it a couple of times as I kept the new dacron sail that I had for 29 and also use the square top when I get a chance to go sailing. Let me know if your interested.
  9. Sq top v Pin Head WA

    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
  10. 16sq sail "flat Top"

    I have had the new sail up the mast, you can probably tell from the pics that the abundance of tress and grass and the lack of water meant that I didn't take it for a sail, hopefully get a chance to get some time to take it for run in the next few weeks. The sail was setup with the foam battens on my normal mast setting, it looks very good with the draft at about 40% and is a bit deeper than I have my Dacron sail setup. Will hopefuly get some pics of it sailing in the next few weeks.
  11. Nacra 16 sq Mylar flat top sail

    Geoff, introducing changes to any class is always a tricky situation, I am in a similar situation with the "old" sail on my boat. The good sail currently on 273 (the one with the red draft stripes on it) is the new sail that was on 29 for the 2010 Nationals at Hervey Bay, this sail has done a couple of races to tuneup prior to the 2010 nationals, 10 races at the 2010 nationals, 10 races at the 2011 Nationals in Port Stephens and 6 Races at the 2012 QLD States, so like you this sail still has plenty of life in it yet. Over the past 2 seasons I have had little chance to do any club racing and when I have I have used the older sail off 273 or the Factory Prototype of the Square Top Sail. My intention with the new sail is to sail it leading up to the Nationals to get it tuned up and then use my "old" sail for club racing until such time as it warrants using the Square Top full time. Introducing this new sail to the class was always going to be challenging, in your situation it may not be worth changing until your existing sail is no longer competitive, there are others in the class that would say they are due to buy a new sail now prior to the Nationals as their existing sail in not competitive, if the new square top was not available they would have to decide to buy a new "old" sail for the nationals or show up with a sail that they know is not competitive, this means that next year they have a new "old" sail that has only done 1 series before changing to the new sail. It is yet to be proven if the new sail is faster across the board, i think it will make the boat easier to sail and therefore may be quicker across the class, until a few of them start sailing against the "old" sail it is uncertain if the "old" sail will become uncompetitive straight away. The factory have tried to encourage or assist the transition across to the square top sail by offering a discount for the first group of sails made, this may assist some people in making the transition during this initial period. I don't think your boat / sail will become uncompetitive over night and therefore warrant selling your boat and moving to another class, the 16sq is a very reliable boat and is an excellent class to sail in, the overall cost of the boat, maintenance and annual sailing costs is very attractive to many people when compared to such boats as A class or F18. I would hope the class can continue to grow and prosper after an initial change over period to the new sail, I would think there will be a mixture of "old" and new sails at the upcoming Nationals in Hervey Bay and that both will be able to compete on the same course. The 16sq was originally released with a radial cut mylar sail, these were very powerful sails that did not respond all that well to loads of downhaul, as I was one of the lightest people sailing a 16sq at the time (since corrected that by getting fat) i needed lots of downhaul to depower in anything above 10 knots, the bigger guys would just power away when the breeze was above 10 knots, as a result on my first 16sq (no. 33) the mylar sail had to be put back together regularly as it would delaminate at the seams, the also had a cross cut mylar sail that was a little more robust but over time suffered from the same delamination issues, during the early 90's the factory changed over to a dacron sail, this was introduced in a similar way. The change to the sail did not affect the bigger guys in the class but it meant the lighter guys could depower without pulling the sail apart, this improved the competition within the class and eventually made the boat faster overall, it also made the boat more reliable as the sails would stay competitive for longer. I still have the original radial cut mylar sail off No. 29, a little while ago I had a sailmaker patch most of the delamination’s so that we could use it on light days, took it for a sail against Scott and Leon when they were sailing with their spinnakers, killed them upwind and could hang on for a while downwind when it was light, swapped boats with Leon so that i could sail his boat with the kite on it and he could sail mine with the Mylar sail, he managed to pull the seams out of the bottom 2 panels so it is pieces again, it also proves that 20 odd years later the Mylar delaminating has put an end to these sails, I also have another radial cut Mylar main and a cross cut one that came from Max's boat, haven’t had a sail with these yet, will have to see if they look like they would stay together long enough. The new cloths are a lot more stable and reliable and don’t seem to suffer from the same issues as the early composite sail cloths. Happy to talk to you about this change over or anything about the boat if you want to give me a call. Pete, I have changed the rotator around so that i can derotate up wind (we did the same thing years ago when we first changed from the Mylar sail to the Dacron Sail but it was not that successful) By changing it around you can still over rotate downwind by using the cleat on the leeward side, it makes it possible to rotate the mast from the windward side with a higher level of accuracy, if it proves successful I may adapt it further to make it easier to do from on the wire, you could put the extra cleats on the front beam but until it proves
  12. Nacra 16 sq Mylar flat top sail

    I have turned the mast rotator around on my boat to give it a try when the new sail arrives, it should work to de rotate the mast and depower the upper section of the sail, will let you know if its succesful. Have you ordered your new sail yet so that you have time to get it sorted before the National ? Corey
  13. Nacra 16 sq Mylar flat top sail

    It looks like the Nacra Factory have released the new sail. Here is a link to the details on Goose Marine http://www.goosemarine.com.au/_content/documents/home%20page/2012%2004%2016sq%20square%20top http://www.goosemarine.com.au/ Great chance to get some of these new sails on the boats and get them tuned up prior to the Nationals at Christmas. Corey
  14. Nacra 16 sq Mylar flat top sail

    Went for a sail yesterday with the new square top, was less than 10 knots all day. Only had A Class's, a hobie 16 and an Alpha Omega to race against so it wasn't easy to compare it to anything else. The sail looks great on the boat and seems to go well, its very stiff compared to the dacron sail and is easy to oversheet in the lighter breeze. Once the A's could get on the wire they got away on the upwind legs but the Kite on the 16sq managed to round up most of them on the downwind runs. The last race had a little more breeze so they could get away on the upwind legs far enough to not catch them on the downwind runs. I was able to trap upwind in the last race and the sail looked very good powered up with just a little downhaul on. The boat feels different with this sail on and responds a little differnent to the sail settings and gust response. Corey
  15. Nacra 16sq Mast Rake

    The way that Mark has discribed it is how most people measure the mast rake on Nacra's We checked a few of the boats on the Saturday during the QLD State Tiltes, most of the setups were just behind the back beam, a couple were between the back beam and the deck hatch (this is where I run mine) and 2 were just infront of the back beam. The 16sq tuning guide that is on Gosses site is a very good starting point for most boats, it was mostly written by Scotty a few years ago and suits heavier crew weights best, there a few tips within it for the lighter crew weights.