Ah the “Hula” (NZL-82) did not go down too well & 2003 was not a good year ! the Blackmagic I’m using here is distilled from the much better vintage year of 1995 (NZL-32)
That day was fairly choppy, something we don’t get very often where I sail and was using the opportunity to try different settings, good point about the gooseneck offset, it is something I have not played with yet. Also here’s look at the main shape
Claudio, the freeboard is little too low anything over 35 degree’s heeling floods the deck and sail settings for the conditions is much more critical with this boat, but when its right, she flys, here with maximum ballast @ 4770 grams on board with the short 390 mm keel draft.
Just out of interest, is the logo made from the same material used on BlackMagic? In the meantime enjoy your ‘Boys own adventure’ in the Greek Islands…
Thanks Row … The Red Bull decals were pinched from one of my sons skate-board projects, they’re screen printed on clear plastic adhesive, not the quality I like to use but I could not find the original EPS files.
Sailing 18ft Cats with the boys was a blast, have new appreciation for multi’s especially after suffering fate of a Chinese Jybe in 25 knt winds on open seas, but survived the indignity and had super time :tand:
was there a better boat to your numbers from? NZL-32 WAS black magic… or was it NZL-31… If my memory serves me correct. NZL-31 did all the heavy lifting. and NZL-32 just slide the dagger in the finals??? both boats were same design. and i love that design… just saying… best boat gets you the best numbers
Thanks for the deco Claudio, I see what I can do with it.
Cougar, the registration of sail # 31 was for Australia One, your thinking is of the sister yacht NZL-38 that was used in all 4 Round Robins of the 95 LVC as the newer and thought to be faster yacht.
Then to everyone surprise they changed to the older NZL-32 and white-washed the competition in the semi’s and took the Cup in 95.
Only 3 weeks until Italian AC 120 championship and I have excluded taking NZL-32 as need new sail plan is needed to have the helm balance the way I like it (no time to order new suit) pity … I was looking forward to taking it to Ravenna.
Have decided to prepare Red Bull as another option and began tuning with DWL hull balance described in post #15, next rough tuning step is find the position of keel fin to match the sail plan with LWL on this boat @ 1000 mm with 7% lead = 70 mm, and the sail plan has static CE @ 44 mm from rear of the mast which should align to the front edge of the keel fin.
The keel fin box is 100 mm and the chord of the straight fin is 85 mm which allows for 15 mm positioning with slot in the deck with locking nut, the mast is 12 mm diameter round that is keel stepped within 40 mm box which gives 28 mm for mast stepping.
At the bottom of the keel slot I’m using 2.5 mm thick shims that are added temporarily taped to the fin, once the right helm balance is found, I’ll then bond in a permanent collar onto the fin where it slides inside keel slot.
Hopefully over the next few days (weather permitting) I can finish this rough tuning process on the water searching for the right helm balance and then can begin the final fine tuning process of sail settings later this week.
After being on the water today to verify CE/CLR I ended up with the CE +2.5 cm from the front edge of the fin to CE for neutral helm balance, what was surprising is that the actual CLR was -25 mm from the design position which gave final Lead of 106 mm or 10.6% of LWL, only difference between the plan and the construction was that plan used trapezoid fin (85-65mm) where I actually used a straight 85 mm fin.
When it is not in our power to determine what is right, we ought to act in accordance with what is probable …and I probably farked-up some where!
I’ve used NZL-32 set of sails had on Red Bull and I’m just happy I gave myself enough adjustment with the mast & keel box positioning on Red Bull as I ended 5 mm too short in the lead with fixed keel fin position on NZL-32. Set-up with the rig as close to 4-8 knots wind as could as was only focussing on getting the helm balance right today only so I can fix the fin into place, over next few weeks then focus on fine tuning of sail settings.
Today’s session started with me forgetting to switch-on Rx sheesh and here’s me looking like a stunned pig in the high beam head-lights of oncoming 4WD on a dark night, thinking I have electrical failure on the boat and then it dawns on me I forget to switch the bugger on, ended up doing 150 metre swim to retrieve her again.
A few hours of trail & error in moving keel fins, changing mast step positions and boom swivel point I finally found a nice neutral helm balance with just enough room to dial-in slight weather if needed, had me sweating for a while thinking I really goofed up on this boat construction after moving a long way past the boat design balance points, but it finally balanced out nicely.
The boat is set-up in race trim @ 4502 grams total displacement with keel/bulb weighing in exactly @ 3000 grams (66%) and was very happy with boats righting. There is 250 grams of ballast just in front of mast which has the bow just a little too light (high) so I will slowly move it forward when I start fine tuning. Here are few pics from todays session.
At the end of the session I start playing little in starting to fine tune sail settings and took quick vid so you can see her in live, excuse the my camera & sailing skills in the vid but most of you know how it is not easy it is to film and sail a RC yacht through a small camera screen…enjoy !
Aware of how moving ballast affects helm, did plenty moving crates of beer around in big boats I’m happy with prep so far, only thing desperately in need of is training/sparring partner …any takers ? got plenty of boats !
Love to come out to help, unfortunately I still don’t travel very well (that’s why I’m playing home alone while the CFO & little terror are playing in London). What about your guys from the AC120 clinic? Perhaps another aching backside with a trip to Nice - I’ll bet Claudio could teach you a few tricks!
Nothing constructive really, sorry. Just keep putting in the stick time…
Hi Jim, you are so right, already found one major problem !..few months ago I changed mast on Jaguar from 10 mm to 12 mm round carbon, was not until yesterday looking at the vids that it became apparent that I had problem when running, the luff curve was too big for the smaller 12 mm mast curve was buckling the man when boom was all way out …can see it here
Simple over-sight had not thought when changing masts :rolleyes: anyway cut new luff curve today and will check it out on the water again next week.
Row not sure FPV system would be really suitable for 2 Channel sailing boat not much you can chance excepting boom angles on the water
I’m happy with prep so far, only thing desperately in need of is training/sparring partner …any takers ? 
