12 metre

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126 F'n Saint

About 12 metre

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    English Bay

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  1. 12 metre

    Let’s Talk Prices!! (topsides )

    Agreed. At our yard, most of the on-site businesses charge in the neighbourhood of $75 - $85/hr tops. Labour I would guess anywhere from about $17 for supervised unskilled labour. $25 for semi-skilled. That's in Canuck Dollars so tops of $65 US Dollars. Anyways, I would say 3x markup on average - and they pay us rent.
  2. 12 metre

    Where Do You Buy Your SS Hardware?

    Just to be clear - ALL Stainless Steel is magnetic to some degree In general terms, austenetic SS (300 series) are considered weakly magnetic and have the best corrosion resistance. 316 is very weakly magnetic to the point of being almost "non-magnetic". 304 (aka 18-8) is slightly less "non-magnetic" and has less corrosion resistance, but better mechanical properties. So if a magnet sticks to SS doesn't mean it's not SS, it just means it is not 316 or 304 or likely any austenetic (300 series)SS Martensetic and Ferretic SS (generally 400 series SS) are magnetic and the Ferretic ones are generally cheaper than 300 series. While they have less corrosion resistance than 300 series, they tend to have superior mechanical properties. As a general rule, the more magnetic a SS item is, the less corrosion resistant but stronger it will be,. If an item is not being sold as SS 304 or 316, I would expect it is not. If it is advertised as simply SS, I would expect it to be a ferretic SS and hence magnetic. The pluses as I mentioned are that in general terms they are cheaper and stronger. For a fastener, I would ensure it is SS 316. For a shackle? I would probably opt for a cheap Seadog. I have a 5/16" Seadog (or Victory) D-ring shackle sitting on my desk right now that had been on the boat for over 10 years with no signs of corrosion that I can detect. However, being in PNW means corrosion is seldom much of an issue. If it were corroded, it is a cheap and easy replacement.
  3. 12 metre

    Strengthening Cabin Top

    I'm not sure I truly understand your question In any event - to answer what happens to the spray adhesive? I assume the spray adhesive remains. Potential for contamination? Yes, but 3M says about their Hi Tack 71 "Formulated to have little to no intrusion in the resin infusion process to reduce delamination risk" I assume AirTac and 3M 77 are much the same since these have been used in resin infusion. On to your second point, I assume you mean how do you do multiple dry layups in one go? I have done it with simultaneous laminations of 1708 and 1200. Just used the spray adhesive to join those two, then a fine spritz on the stitched mat portion of the 1708 and offered it up, then wet it our with a foam roller followed by squeegeeing with a plastic spreader. I don't know if this will work with more than two dry laminations at a time. I doubt adhesion will be an issue, but I suspect full saturation of the fabric would probably be one. So if you want to do more than two laminations, you may well have to wait until the initial laminations have cured. Good idea in that case to use peel ply so you don't have to prep the cured epoxy/glass. On the other hand, there are limits on the wet layup method as well. I think you would have to wait until the innermost laminations have begun to gel before applying subsequent laminations.
  4. 12 metre

    Strengthening Cabin Top

    I was just saying that as an alternative to doing a wet layup over the part, it is possible to do a dry layup, which is how I prefer to laminate when possible. I was only talking about the overhead lamination of glass fabrics . Any part/beam was not part of the equation - I believe it would have to be fastened in place first using either method.
  5. 12 metre

    Strengthening Cabin Top

    An alternative to the wet layup with cabosil is to do a dry layup with a light misting of spray adhesive on the fibreglass. Spray adhesives are used in resin infusion to keep the dry stack in place. I have used AirTac which seems like an aerosol version of contact cement. 3M 77 is a similar product. Actually, it looks like 3M makes a Hi Tack version designed specifically for resin infusion: https://www.3m.com/3M/en_US/company-us/all-3m-products/~/3M-Hi-Tack-Composite-Spray-Adhesive-71/?N=5002385+3290539321&rt=rud Only works with epoxy. I have tried it on polyester, but it appears that the styrene or some other chemical dissolves the adhesive because the layup fell off just as the cloth was becoming saturated. Just make sure to wear a hat have a lot of drop cloth in place because there will be lots of drips.
  6. 12 metre

    Where Do You Buy Your SS Hardware?

    For a wide selection of SS hardware, there is the Seadog stuff that I believe is imported from China - a few dealers in Florida listed here https://sea-dog.com/dealers/top_dog_dealers Their stuff is okay, a lot less than the name brand stuff - but the hardware has no load ratings so you have to know what size you need. Similarly there is the Victory line of SS https://victory-products.com/. Not sure if there are dealers in Florida.
  7. 12 metre

    what is it?

    You mean this one? So fast they never took it to the 2017 6mR Worlds in Vancouver.
  8. 12 metre

    Sad Sack 12?

    Update on the Jenetta resto: Looks like she was launched sometime in 2019 from the Robbe & Berking yard in Germany. Looks much better than new I suspect. Discovered a few things about her recently in a book about RVYC that was on the bookshelf of a Starbucks in my neighbourhood. Apparently brought over on a freighter to Vancouver in 1954 by D.P. urry and raced out of RVYC in the 1950s. Had the distinction of being the longest 12 ever built having an LOA of 72 ft. It looks like she had some good close battles in English waters with Vanderbilt's Vim back in 1939. For anyone wondering about her new livery, it is the tartan of the University of Glasgow where Mylne attended Photos of Jenetta as she was being pulled out of Pitt Lake can be found upthread, but I've included one below for comparison with some recent photos of her 2019 launch and sailing
  9. 12 metre

    Showtime capsize on return trip

    Pretty certain the keel loss on Charley predates Drum. Charley was owned by Nolan Bushnell and was a Holland design as well. She was a 67 foot IOR sled that took line honours in the '83 Transpac and '84 Vic-Maui. Lost her keel on delivery back from Vic-Maui IIRC. Probably didn't come across as such a media event since: a) Simon Lebon wasn't onboard, and b) the crew managed to keep her upright for the duration of the trip
  10. 12 metre

    what is it?

    True with the old ones, but the newer ones look to have at least soft chines above the water and quite snubbed bows - a bit like Mariner, the much maligned 12 Metre. Probably not most peoples cup o' tea, but I kinda like the look. Freeboard on these still look much higher than the boat in question.
  11. I have been through the previous threads here on tubercles, but a few interesting things have come to light in this one: 1. Location of the tubercles. On longboard, the tubercles are located more towards the rudder root, while on Rambler 88, they are closer to the tip. Rambler seems to more closely emulate the humpback whales which have them more densely spaced near the tip as well. This would make sense since a stall typically begins near the tip. 2. Sizing of the tubercles. The chart title translates roughly to "Lift curves as a function of the amplitude of the bumps". As expected almost everything in sailboat design involves trade offs. In this case, the rudder under study without tubercles is capable of generating measurably higher lift at the expense of a quick and rather sudden stall. The 5% tubercle size has the same slope to the Lift/AOA curve and extends the stall angle by about 3 degrees, but the stall is much less abrupt. The downside is max Lift is reduced 25% The 12% tubercle size has similar Lift/AOA curve as well at lower AOA, but tapers off. Stall angle is extended by about 6 degrees and again is much less abrupt. Max lift is reduced by about the same 25% as the 5% tubercle size. The takeaway for me here is that (at least for the rudder under study) if you want to go with tubercles, go big or go home. Much more forgiving than one with smaller tubercles with the same max Lift extended a few degrees further. Of course if stalling is not an issue, you are likely better off with none at all.
  12. Exactly how Hobie 14s and 16s function - except they have the added element of hull asymmetry.
  13. 12 metre

    Gary W Mull

    Bigger sibling to the Pocket Rocket 22, of which I can't remember how many were built. I believe Sparky met her demise several years ago, hitting some rocks and tearing up her hull IIRC. Crewman seriously injured as well I believe. There is an old thread on it somewhere here in SA.
  14. 12 metre

    To fair or not to fair...The keel that is!

    Having thought about it, you probably don't need a quarter tube, which would be difficult to find. However, what one can do is take a half tube and either cut it down the middle, or mark off 45 degree angles on both sides. and sand down to the marks with a belt sander. Yes, with a half round you can bury the edges in filler and I think I mentioned that, but then you have two tangents to fair to. Like I said, kinda works and is probably good enough for most PHRF racers, and almost certainly better than most out there. Your method is nice and relatively easy way for most people to fair the keel especially one with a constant chord length. Also agree you can use the half rounds for foils other than the NACA 4 digit series, but I wouldn't try it on a 6 series foil. The nose radius such as it is is considerably tighter on those.
  15. 12 metre

    To fair or not to fair...The keel that is!

    That will kinda work -subject to a couple of caveats: - For a keel with a trapezoidal planform (like the S2 9.1) the leading edge radius tends to decrease across the span so a uniform glass fibre tube will likely have too large a radius as you progress down to the toe. - There is an assumption the foil section is a NACA 4 digit, which does use the arc of a circle for the leading edge. However the angle of the arc is only 90 degrees, so a quarter section should be used not a half section. Using a half section, there will be a line of filler laid down to smooth out the transition from half tube to foil. Probably creates an okay surface and will be an improvement, but I don't know how truly fair it will be. One needs templates made up to do the job right, but I don't know if its worth the time for most people. There is an article on the topic: https://www.epoxyworks.com/index.php/how-to-loft-airfoil-sections/