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Anyone know how to sail a Mumm 36? Because we just bought one! It seemed like the right think to do after reading the forums and being specifically warned that they're difficult to sail to their rating and chew up inexperienced amateur racers. That's us! We were loosing our maintenance war with an aging J/30 and thought, how hard could it be?! We're having a blast, sailing her everywhere and trying to grab every race possible as the season winds down. The fun aside, and perhaps not surprisingly, we're not doing very well. We have the polars and just seem to be .3-.5 of a kt. slow no matter what we try. There are a few caveats. The mast jack did not come with the boat and we don't have a rod loose gauge yet (or a guide to what the numbers should be if we did) so rig tuning has been a lot of tacking back and forth and making slight adjustments to keep the rig straight (we can't seem to agree on the straight part either...). When we race, we spend a lot of time saying, "well this isn't working, lets try x", and, "well x certainly didn't work, time to move on to Y". We're generally finishing races alongside the J105's so we're definitely doing something, likely a great many things, wrong. I was hoping someone out there who might have spent time on this slightly geriatric racing machine would be able to impart a few tips in terms of trim and general racing. We've been generally sticking the main doctrine of higher traveler, more camber, more twist on light/choppy days and flatter leach, lower traveler, when the wind starts to build. We keep the no.1 close and leach closed in the light stuff and closer and more open as wind comes up. We pull on backstay, outhaul when the wind is climbing and keeping them soft when it's not. Definitely pull harder on the running stays when there is wind but probably not as hard as we should be (I'm terrified of the 6,500 lbs mark as we don't have a load cell). Not exactly sure how/when to be using the vang, been playing it like I would on the 30. Should we transition to dip pole when spin jibing? There is definitely great info on the form (we have our tacking choreography down!) but cant seem to find just a general tuning/trim guide for this boat. We understand that it will take time to learn this boat and sail her efficiently, if we ever figure it out at all. I'm aware that this post will probably attract all kinds of hate for us newer folks in over our head with too much boat and trying to stage a racing campaign. That's cool, I hope that I might be as cool/experienced as you someday. If anyone else would be so kind as to throw out a pointer or two, we'd be grateful. -Josh
Hi Guys, I sail a Javelin Skiff Here's a video to give you a bit of an idea A two handed skiff (crew on the trapeze), square top main. And in my instance the main sheets off a bridal at the back of the boat and we use boom sheeting. I've put this little grid to together of the main sail and it's controls, and then filled out the effects each has. Could you please let me know how well I've done and perhaps some feed back. You'll see I've got a few questions in there too that I'm not 100% on. Controls and there effect on the mast and sail... Mast Boom Sail Purpose Cunningham / Downhaul Pulled On: Bends the mast forward in the middle. It will bend the mast the most where it is weakest (tip/tip) and the least where it is stiffest (Perhaps between the base and goose neck). Pulled On: It will reduce the effectiveness of the Vang tension, and some load will transfer to the mainsheet Pulled On: Primary effect - the mid draft is reduced, making the sail not as deep in the middle. Secondary effect - load is reduced in the leech allowing it to twist. Sheer - is to the aft compared with the middle of the sail, which increases tension between the aft square top corner and the middle luff of the sail Primarily to control the power of the mainsail (flatten it for stronger wind, or for very light winds). Can be played even for gusts. Q. By preloading it more does it improve gust response of the mast (in the tip)? Vang / Kicker Pulled On: It bends the mast forward at the middle and pulls the tip of the mast aft. Vang vs GNAV... The GNAV puts the bend further up the mast compared to the more traditional vang. Pulled On: It places a bending moment on the boom to the outboard end by the Gooseneck and Vang load Pulled On: Some tension... It makes the leech stand up, as the line of tension between the head and Clew pulls the roach to windward. Lots of tension... it flattens the sail in the middle and allows the leech to flatten off. Sheer - as this tension pulls the mast tip aft it creates a sheer to the aft compared with the middle of the sail. Q. What does this mean for the sail? To control the twist of the main for the conditions. More wind more tension to hold the leech twist required. Choppy condition less tension to allow more twist widening the boats groove of power allowing you to steer more yet maintain power at these ever changing angles. Outhaul Pulled On: Could add some tension to the head of the mast bending the tip back. Pulled On: Places compression on the boom Pulled On: Primarily pulls the bottom of the sail tight taking out draft, also pulls tension from the head to the Clew flattening it out along that line, and all of the rest of the sail between the head, tack and Clew. Q. Am I over using this and causing the stress lines I see in the upper half of the sail between the head and the Clew? To control the depth of lower 1/3 of the mainsail Mainsheet Very little, unless the vang tension is minimal and the mainsheet is sheeted on hard. Also depends on the amount of purchase setup. Allows you to adjust the sail as a whole in and out to match the angle of the wind minimal, unless the vang tension is also minimal. This may be the case in very light wind where it's used to control the leech tension (sail twist) Adjust the sail as a whole in and out to match the angle of the wind Baby Stays / Lowers Pulled On: Shifts the mast bend caused by the Cunningham and Vang to be moved further up the mast, and limits the bending effect of both controls Tends to flatten the upper sail (perhaps at the 1/3 point instead of the 1/2 point) Vang and Cunningham tension affect the leech tension, and the flatness of the Square top. Pulled On: Allows you to keep the main powered up and adjust the leech and square top to the right amount of twist for the conditions (flat, choppy) Thanks, Hamish