JulianB

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327 F'n Saint

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About JulianB

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    Anarchist

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    Sydney mostly
  • Interests
    Sailing, eating, designing

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  1. If I had to name someone it was Tim Coventry who drove the Laser into the Olympics. Probably Geoff Martin was up to his eye balls in it also. I have a strong recolection of Ian (Bruce) and Ward (McKim) being very very wary of the then IYRU and what Olympics would do to the Laser. I'm not sure what cocktail we drank while having this conversation, but Barbra was there, in Point Claire, and it ws a very good night. But I do 1000% agree with the comments re Meroca Sailing and there preference for Olympic Boats. Being Olympic adds 10% approx in cost but that is a very small price to pay, if you sit down and think about it. Purchase price is irelevant! Think running cost, and Olymics brings mass and dealers and parts and certianly. jB
  2. JulianB

    Upwind Tasar/NS14

    I get my back up a little with all this. Yes, NS14's where born in our living room in Northbridge in about 1961-2, yes we were stalwarts of the NS14 history, we are all life members of NSC, and we made a lot of NS14's. From about 1965-1975 we did roughly 100 NS14/y. About that again where built by others. I remember Colin Thorn's mouldy, as one of those, but then in 1970(ish) my brother Mark won a huge Nationals in Canberra in the Medium Dribbly. Ya got to remember I was 13. Mark and Dad went right back to basic's, worked out what it was they were trying to achieve, they drew this all new shape which was a complete departure from the std, build 2 boats, one for John Diacopolous (who is still my lawyer) and the other for Mark and Carolyn (his then fiancée) and that was Medium Dribby. We then built approx. 100 - 150 Medium Dribby’s per year, but there where always changes, mostly to the rigs but more than anything, some major departures to the hull shape. Thinking back, I was quite possibly the catalyst for the Nova (pre-cursor to the Tasar) because Mum and Dad where a bit big for the NS14, so Dad and I started sailing and very likely Mum got “pissed off!” And I do remember dieting (at 14-15) to make the then 250lbs (111kgs) minimum crew weight. That weight limit no longer exists. Peter Warner certainly sailed at a weight less than that, I occasional bump into Huge Tait, and the 100kg number has been bandied about often. (both are multiple NS14 Nat Champions) Peter sailed with me on AAMI when we won the 1991 worlds and broke the course record. Anyway, Most likely, as wives often do, Mum got her way and the Nova was born, so this was a NS14, with bigger sails, and it took off very fast. Enter Ian Bruce who Dad meet at the 1972, but more fully at 1976 Montreal Olympics, Dad was part of the team, Mark was sailing FD’s, Ian was sailing Stars. (Ian being the conceptual father of the Laser, Laser ii, all that stuff, he also lived in Montreal) Most of the summer of 76-77, Ian lived in our house (the same Northbridge house) and the Nova became the Tasar. Now, there are probably 3000 NS14’s in the World right now, and there are probably a few more Tasar’s. The Tasar has brought Hi-Performance body swung 2 person sailing to the world. I think it is very fair to say that the NS14 was never placed to do that. The list of Olympians who sail the Tasar out of Seattle is legendary. 25 year old Tasar’s win World championships, the Tasar worlds occasionaly hit 200 boat but are rarely ever under 100 regrdless of where they are held, presently a huge entry list for the Japanese worlds is amassing. Both boats do amazing jobs, but comments like “Dad abandoned the NS14” are juvenile. He simply moved on, very likely while being prodded by Mum. Comment like “a 50 year old design” belittles the detailed refinements that happen when you have a large SMOD and the Tasar has brough this, what was unbelievably foreign sailing concept to a whole world of sailors that don’t reside in Australia. Think momentraily about the comments of our Seattle friend, few posts back! The NS14 class should embrace and lever off the development of the Tasar, because certainly it came from the thinking that happened right back in 1960 and latter in 1970 when Dad and Mark re-thought what it was that is important in boat design. All the wind-tunnel work, (paddle pop masts) all the foil work, the brilliance that was Ian Bruce was mixed in and it has changed the world. I then embraced that, fostered by Dad and Ian effectively became my 2nd father, but embelished by the time I had in NS14's along with Moths, and skiffs. All the Primes, the Entrad’s the AAMIs, the 49er’s the 29er, all of that ethos was fostered back in that same house by the ambiance that was thick in the air. By getting their backs up in the air, as they do, every time this comes across the screen, the only class they are doing a dis-service to is the NS14. If that is what they want, so be it! I doubt the NS14 will ever embrace or god forbid they lever off the development of the Tasar, the 9er's the B18's, it too far beneath them. I have to add, I did laugh Rainbow, I picked my words very carefully, but knew I would get a bite. And bite you did!! I guess there are possibly another 10 of you just itching, right now to also bite. Bite away, Dad's obvioulsy left us, and I have very thick skin, but maybe think more global. jB My brother Mark, maybe 6-7 years ago, I need not comment on the name of the lane leading to Northbrigde Sailing Club (where do you think NS came from)
  3. JulianB

    Upwind Tasar/NS14

    Rainbow, no issue with what you have said. And BTW, at no stage did I say the Tasar was faster than a NS14. What I do know is Tasar sailors regularly opt for planning up wind. The very good NS14 sailors that I know and interact with regularly have never mentioned it, so I have assumed it dose not happen often, if at all. Loved my NS14 days, never denied that, not sure I like where they are going, but who am I to judge. Have a gopod day, jB
  4. JulianB

    Upwind Tasar/NS14

    touche!
  5. JulianB

    Upwind Tasar/NS14

    How long is a piece of string???
  6. JulianB

    29er Sail Track

    Don't switch to Stainless (strap), you are just buying yourself electrolysis issues. As has been said, the new Boom Gooseneck is a huge improvement and will solve all the problems. It separates the load, takes them away from the middle, it’s thicker so it spreads the load even further and it has a lot more rivets to transfer the load from the GN to the boom. But if you wish to stay with the SS fitting, then get a bit of say 4mm x 20mm thick alloy plate and wrap it right over the front of the boom, make sure you have 2 x 3/16” monel rivets per side to transfer the load (one rivet can go thought the SS fitting, but you need another). Guys if you stop evolving, then the old fitting are just fine, but more and more vang sheeting, loads up the front of the boom. We load tested the whole thing and you have about 1 tonne going across the GN. The other big plus of the new GN is it eliminates boom rotation and that in turn eliminates a multitude of other sins.
  7. JulianB

    Upwind Tasar/NS14

    Superg, Any course that is less than 90° TWA is upwind. Lots of boat can plane beam/shy reaching and therefor technically are planning Up-Wind. But their VMG will be appalling! About 20 years ago, some passionate people within in the then ISAF (now WS) tried to define Hi-performance and it was words like "sails faster than the wind most of the time". Along with that, they tried to define "planning up-wind" and at the end of the day, the whole lot got thrown in "the circular filing cabinet under the table" but the "planning up-wind" sort of worked and it was geared around VMG. Take a Tasar, it’s TWA up-wind in displacement mode in low 40’s°, say 42°, 5 knts BS approx. so 5knts x cos 42° = 5 x 0.743 = 3.715 knts VMG. That same Tasar, if it “heats up” 5° can transition to the plane, do the same sum, but the boat is now doing 6.5-7 knts so say 47° and 6.75knts so 6.75 x cos 47°= 4.6knts VMG. So it’s pretty obviously beneficial to plane up-wind. ~~~~~~~~~~~~~~~~~~~ Need to stress this is “all other thing being equal” which they just about never are. Tasar’s (in fact all 9ers) have very V-ed for-foots, great for carving upwind, slicing waves, etc. (People need to subscribe to AYR’s.) They have quite low squat rigs so low CoE and therefore highish SCP. On the other hand NS14’s are very U-ish, which is perfect displacement sailing particularly up-wind, bow dose not lift as much and forward sections are finer, especially when they did away with the dish rule. So they are geared to stay displacement which they do very very well. Rig is more rectangular with higher “aspect ratio” so probably higher CoE, so lower SCP. Both boat have over-rotating masts and in the case of the Tasar very small LE radius. So both boat have very slippery rigs, low drag / high efficiency! I was looking at a photo of Markutu which was NS14-3, 1963 circa, and along side it Takino NS14-2500 Circa 1972 (I was 14) and the evolution that happened in those 9 years was historic. Also, virtually all in Australia to go from #3 to #2500 in 9 years is an extraordinary example of growth of a class.
  8. JulianB

    Upwind Tasar/NS14

    Ok, firstly, NS14 rarely plane up wind. Tasar can plane up wind. Often. (assuming you classify that via WS standard) It all due to maths, very very simple really. Both boat have a minimum hull weight of 64kgs (140lbs), NS14 sports a lighter mast but only by a few kgs. Tasar has another approx 30+kgs of crew weight and that adds a significant amount of RM [Righting Moment) LWL [Length Water Line] is the same, width is the same, CoE and CLR are ostensibly the same. All up weight are 30-35kgs apart. So NS14 can generate 100kgs (crew weight) x (1m (1/2 bean) + .3 (CoG of crew outside the gunwale))= 100 x 1.3 = 130kg/m RM (the NS14 has now no minimum crew weight, it used to be 250lbs (113kgs) but it is now being sailed by much lighter crews (which is why the Nova/Tasar happened) Tasar is 130kgs x (1m +300mm) = 169kgs/m RM. So the NS14 has something like 25% less RM (169/130=75%). All up weight is say 64+15+10+100 = 189kgs (NS14) where as a Tasar is 30kgs more so say 220kgs so about 86%. So the Tasar has 25% more grunt and weighs only 14% more, pretty simple maths. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Next bit, board height. Assuming the sections are suitable, then it all about maximizing the CoL / CoD ratio. By a suitable section I am saying laminar flow (lowest drag) and that then means an AoA of about 1.8-2d (yawl). So if you have to much C'Board down you will then be running to low a yawl angle and the board will not be operating at max efficiency. To little board down and you will be running to high a AOA/yawl and probably drop out of the bucket and definitely out side peak efficiency. So board height is very important. You also need to remember that a lot of the board is inside the case, so a 1" (25mm) extra in the water is infact quite a few % so Bruce Kirby is 100% correct. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Last bit of maths. The ability of a C'Board to generate lift is a x-sq law of speed. So a Tasar doing 5knts displacement speed (Hull speed) 5(knts) sq-ed = 25 Then it jumps to planning up wind speed at say 6.5-7knts sq-ed = 42.25 So you need about 60% of the area to operate with the same efficiency. But you need to remember it effective area (not actual) so lifting the board 50-60mm is about right. Planing, the speed jumps to say 10knts, the actual amount of area you need is greatly reduced, the limit is how far you lift it under the vang. jB
  9. JulianB

    Upwind Tasar/NS14

    Do you want me to stay out ofthis or come in??
  10. JulianB

    29er Sail Track

    The tube(s) of MA300 I have outside are 400ml. So there is 200ml of A and 200ml of B. You need about 1/10 - 1/8 of that to glue on a 29er topmast track on. 40-50ml (mixed) of Plexus. Probably why the small pack Ovington/Nautivela have are so popular. They are in a syringe type packaging. Just put a bead about 4mm in dia down the middle of the plastic track, then use masking tape every 100mm to hold it on. We put a bit of T section alloy (3mm WT x 18mm x 18mm) down the track, keeps it straight. Once it gels, we just use a chiesil and remove the excess. If you want to tart it up, fillet it with black silicon. ~~~~~~~~~~~~~~~~~~~~ Again, you can tell the MA300 has not been loved for a long time and no idea why I have it. Way past it's use-by-date! MA420 is a 10:1 ratio, so the A tube is 1/10 the size of the B tube.
  11. JulianB

    29er Sail Track

    We tend to use the MA420 and have had a lot od sucess with it. https://itwperformancepolymers.com/products/plexus/general-purpose/plexus-ma420-ao420 It's pretty quick, so you need to be well prepared. MA425 is very good, but you need to prepare the surface more than with 420. I would be using MA422 before MA425. I do have a tube of MA300 in my front yard, but can't remember why, it's 1:1, where as the others are 10:1. Both Ovington and Nautivela have small single shot/use methacrylates, and I am told they are popular. I have always wiped it down with a Methly Cloride or a Methlyated Sprits after giving is a super light sand/scour. The PVC (sailtrack) needs to be clean also, no oil (used in production) again either of the Methly's will do the trick. jB
  12. JulianB

    49er - new style mast

    I hope to transit a few times in November, and I would love to drop in, have a chat with you and whom ever. Did a "skiff chicks" thing a month or so ago, great to see the much better sex having a great time. jB
  13. JulianB

    49er - new style mast

    Rambler, I owe you a fuller answer. Re visit, QLD/Covid has destroyed many plans to go sailing on Wraith of Oden, and therefore transit of you part of the world. Plus presently, I am a shipwright again, taking space in Somersby, doing the project I expected to be built in Milan, then Melbourne (2 strike rule) so got a tad on. Got a wedding in Brisbane early Nov, but I think I'm flying. Re Tow-preg, it's pre-impregnated filament, so instead of the carbon filament being dry, and passing it through a bucket of resin this stuff comes with an exact amount of resin in it. You keep it cool, very similar to "pre-preg" unies. It was developed from the aeroplane industry and aero-space, so tolerances are a lot finer and therefore repeatability is that much greater. But it also requires very different tooling, as in hard anodised alloy tools with no release medium, and a lot of the old tools are "polluted" and can't be re-used. Re Plexus, I think its ITW https://itwperformancepolymers.com/products/plexus and it is a methacrylate, not a epoxy. Significant differences between the types for instance in one applicant MA425 dose not work where as MA420 dose work. And the opposite is true. Again we tend to use MA420 but you need to go look at what it is you want to do and go from there. WRT gluing the castellation rings on, we have Teflon washers and use MA420 so there is no Alloy – Carbon contact. AL-C is the worst, they eat each other. SS-C is nowhere near as bad. Monel or Ti to Carbon are almost benign. And Hard-anodising (of the alloy) also greatly reduces the chance of electrolysis. Re key plates and the alike, that are through riveted. 1st think, for electrolysis to happen you need electrical conductivity and you also need a medium (acid) which in this case is salt-water. Barium Chromate (otherwise known as Cocky-shit) dose a amazing job, but its possibly carcinogenic. Tuff-gel is also amazing, but then again so is slightly coagulated varnish (it works via water-proofing). The trick is to do it well and use one of the inhibitors.
  14. JulianB

    49er - new style mast

    Firstly, Plexus is Methacrylate, I think it's abbreviated as MMA. Not sure it's related to Epoxy, I am not a chemical engineer, but it sure smells different! Its primary use is gluing your cars together, and it used correctly is truly amazing stuff. But there are a multitude of Plexus’es and you have to use the right one for the right job. We tend to use MA420. It is slightly elastic (far more elastic than epoxy) and like any plastic it goes soft at high temperatures. So a hot carbon mast with no venting in Australian sun, goes way beyond most plastc’s critical temperatures, and also beyond Plexus’s “yield point”. Used well, it's a really great product, but with the 49er GN's we have upped the surface area about 25% and we are venting the masts.
  15. JulianB

    49er - new style mast

    It's a all new design on all new mandrels using tow-preg, which your right, is a game changer. To over-come, we have insulated the alloy with GRP or teflon washers or glued the fittings on with Plexus.