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2024-07-23; 13:03:50 EDT
Member Since
2024-06-18
Posts: 53
Everyone i've shown my backstay assembly two has also commented on how homemade it all looks, i do most of my tensioning via the deckhouse and forestay but the block in the back snugs up too. I would prolly have liked to see adjustable ends but i guess theres too much slack to takeup back there. Its not too bad to get a set of dies for properly terminating line! Especially if you already have a press McMaster Carr is my goto for swage fittings and the like.See the original archive post
On Tue, Jul 23, 2024 at 8:14 AM ROGER PIHLAJA <roger_pihlaja at msn.com> wrote: > Hi Brian, > > Attached below is a post from the archives re an improvement in the OEM > backstay adjuster. The OEM backstay adjuster does not lend itself to rapid > and reproducible adjustments. Especially if you want to race your boat, > this is a quick, cheap and effective project. It doesn't affect your PHRF > rating either! > > Roger Pihlaja > S/V Dynamic Equilibrium > 1978 Sanford, MI > > ______________________________________________________ > I mounted a Harken #144 swiveling base with #150 CAM-MATIC cam cleat, #137 > eyestrap, #071 stand-up spring, and a 2.25" dia. block just in front of the > starboard side backstay chainplate. The standard backstay adjuster line > will thread up to this assembly like it was designed to be there. Thru-bolt > the Harken swivel base to the gunnel with silicone RTV, four #10-24UNC X 1" > stainless steel flat head machine screws and use a #10 stainless steel > fender washer under each nut as a backing plate. > Before drilling any holes, thread up the backstay adjuster line and > experiment with the position of the swiveling base. You will find there is > a sweet spot just in front of the chainplate where the line will run fairly > into the block without chafing on the backstay or blocking the boarding > ladder. Don't use the smaller Harken #205 swiveling base because the base > is right near the boarding ladder & sooner or later, someone is bound to > step on the swiveling arm. The Harken 144's swiveling arm can stand up to > being stepped on and the 205's can't. > The swiveling arm on the Harken 144 makes trimming the backstay adjuster > very easy from either side of the cockpit. Be sure to mount the swiveling > base so that the arc of the arm's movement won't allow the adjuster line to > flop overboard. I marked my backstay adjuster line at 2" intervals with > colored magic marker so I can reproduce the backstay tension. > In order for the backstay adjuster to be able to cause any noticeable > difference in lee or weather helm, you need to have the rest of the rig > set-up properly. With only the slack taken out of the backstay tension, the > inner (lower) shrouds have to be set quite tight. The outer (upper) shrouds > just need to have the slack taken up. Sight up the mast and be certain the > mast is not bent or leaning side-to-side or bent fore-and-aft. > The mast should have a slight aft rake to it, about 2 deg max. Now when > you tighten up the backstay, the forward lower shrouds will restrain the > middle of the mast. The head of the mast will be pulled aft. This will > simultaneously take up slack in the forestay and induce a slight bend in > the mast. (Note: NOT recommended with IMF mainsails!) > Tightening up the forestay is desirable for genoa sail shape when beating > to weather. If your mainsail is properly cut and not blown out from old > age, the mast bend will cause the mainsail shape to flatten out into an > aerodynamic shape that is better for high winds and beating to weather. You > will also move the sail plan's center of effort aft, thus inducing weather > helm. > This is an inexpensive modification that works so effortlessly that Stan > ought to consider it as a factory option. My backstay adjuster has been > absolutely bullet proof for 10 hard sailing seasons. > Roger Pihlaja > S/V Dynamic Equilibrium > 07 Jul 98 > ________________________________ > Thanks for your detailed description. Sounds like a good solution. Did you > have any trouble getting to the back ends of the through- bolts? Seems like > a long narrow reach. Can you get them from inside the lazarette? > Your mention of IMF mains got me thinking, since that's what we have. > Maybe with the furling tube adding stiffness to the spar, I won't be able > to induce much bend anyway, so prudence on cranking down the backstay is > probably wise. It's also likely to have some ill effect on the performance > of the furler, if the IMF furling tube isn't straight. My new forestay has > a turnbuckle (required by the CDI furler), so I can do more adjusting there. > Your recommendations for adjusting the upper and lower shrouds will be > very helpful, too. Thanks again. > Gary Sanford > s/v Raven > 07 Jul 1998 > ________________________________ > The Harken 144 swiveling base is mounted on the starboard side gunnel just > in front of the backstay chainplate. The job will require 2 people, one > down in the lazarette to hold the wrench and a helper up topside to turn > the screwdriver. However, the gunnel is wide enough to easily reach up > there with a wrench. You were probably thinking the swiveling base mounted > on the top of the transom, which would be a very long narrow reach to get > at the thru-bolts on the backside. It turns out the top of the transom > isn't wide enough to mount the swiveling base. > My roller furler has a turnbuckle as well. This forestay turnbuckle is > used to adjust the static rake of the mast when there is no backstay > tension. For a conventional mainsail, the proper mast rake is about 2 deg > to the rear. I don't know what an IMF mainsail requires for mast rake. You > may have to experiment with mast rake until you get neutral helm. You may > find the best you can do is have a slight lee helm in light air building up > to neutral helm in a moderate breeze & then weather helm in heavy air. With > an IMF mainsail, I would adjust the forward lower shrouds somewhat looser. > Then, increasing backstay tension would simply increase the rearward rake > of the mast without bending the mast. This would get you the forestay > tension you need to be able to point to windward. The chances are your IMF > mainsail isn't designed to respond to mast bend anyway. Remember, I have a > fully battened conventional mainsail & I specified my mast bend parameters > to the sailmaker when I ordered the sail. I would imagine bending an IMF > mast & then operating the furling mechanism might cause the mainsail to > chafe inside the mast & put a lot of stress on the furling mechanism's > bearings. Is an IMF mast much stiffer than a conventional mast? I've never > seen one off the boat. How much heavier is an IMF mast? > Roger Pihlaja > S/V Dynamic Equilibrium > 08 Jul 98 > ________________________________ > Had the IMF apart 2 weeks ago. Any rake would be bad news, since the > mainsail is wrapping around a tube with roller/spacers top and bottom. If > the tube changes distances to the mast wall I do not think the sail would > go in (i.e. the whole thing would jam up). The IMF is about two inches more > fore/aft and about ½ to 1-inch greater in width, than other masts on boats > that size. It’s very stiff, but I have never seen the GB standard mast. > MJM > ________________________________ > The OD of the forestay wire & the rigidity of the headsail foil have very > little to do with forestay sag. Forestay sag is primarily controlled by the > amount of backstay tension + some secondary & tertiary effects caused by > other details related to the way the standing rigging is setup. The use of > 3/16" OD wire for the forestay permits the backstay adjuster to be really > cranked down hard with no fear of forestay wire stretch or fatigue cycling. > The use of the larger diameter wire also introduces an additional safety > factor to compensate for corrosion, mechanical damage, etc. > I have my backstay adjuster setup on a Harken 144 swivel base, 150 > Cam-Matic cleat, 071 stand-up spring, & 001 single 2.25" block mounted on > the starboard side gunnel right at the transom. Backstay tension is quickly > adjusted by pulling on the backstay control line thru the Cam-Matic cleat. > The 144 swivel base & 150 Cam-Matic cleat allow the backstay tension to be > adjusted from virtually any helm position. I used the 144 swivel base > because the backstay adjuster is right near the boarding ladder where it > might be accidentally stepped on. The large 144 swivel base is rigid enough > to step on without damage, while the smaller Harken swivel bases can't take > such abuse. The backstay adjuster control line is striped every 2" so that > the backstay tension is reproducible. > My standing rigging is setup such that increasing the backstay tension > simultaneously reduces headstay sag & bends the mast for flattening the > mainsail. Both actions are desirable for sail shaping in heavy air. I have > a fully battened conventional mainsail, which is cut very roachy & is > designed to respond to mast bend by flattening. I use only one mainsail, > but it has 2 jiffy reef points. Needless to say, backstay tension is one of > the most important sail shaping controls on Dynamic Equilibrium. > Good grief! I just gave away a couple more racing secrets! Hopefully, no > one else is listening. > I guess I don't understand your question re noticing any difference when > the sail is fully extended given the weight. The only fully nylon sails are > spinnakers. Did you mean, have I ever noticed a difference in light air > behavior between a Dacron genoa & my Cruise-Lam genoa? If that's your > question, the answer is the bi-radial Cruise-Lam genoa has a better sail > shape under all conditions vs. the standard Dacron genoa. In heavy air, the > Cruise-Lam + bi-radial construction genoa's sail shape is much better as > the standard Dacron + cross-cut construction genoa becomes hopelessly > distorted. > The secret of Cruise-Lam's longevity is the Dacron outer skins. The Dacron > provides chafe, UV, fatigue resistance, & environmental pollution > protection. The reinforcing Kevlar scrims & Mylar film core are buried > inside the composite sandwich & are thus protected from the harsh outside > world. Unprotected Kevlar & Mylar would be expected to only last one season > or less in the marine environment. > Roger Pihlaja > S/V Dynamic Equilibrium > 12 Jan 2002 > ________________________________ > From: ROGER PIHLAJA <roger_pihlaja at msn.com> > Sent: Monday, July 22, 2024 2:06 PM > To: The Rhodes 22 Email List <rhodes22-list at rhodes22.org> > Subject: Re: [Rhodes22-list] Traditional Mast Backstay problem > > Hi Brian, > > On S/V Dynamic Equilibrium, my 1978 Rhodes 22, I had a local wire rope > rigging shop duplicate what I had when it was time to replace the double > backstays. As you described, it is one piece of cable bent in the middle > around a SS thimble. My backstay adjuster and sockets for the traveler bar > are also like yours. I used this backstay for many years with the GBI gen > 2 traveler bar. When it came time to upgrade to the latest Gen 3 traveler, > it slipped right into place using the same backstays and sockets. > > Roger Pihlaja > S/V Dynamic Equilibrium > 1978. Sanford, MI > Sent from my iPhone > > > On Jul 22, 2024, at 1:46 PM, Brian Ferguson < > brian.a.ferguson76 at gmail.com> wrote: > > > > To my fellow Rhodes traditional mast-ers, > > My current backstay consists of a single continuous piece of ss cable run > > bent through a thimble to mark the halfway point The thimble is the > > connecting point to the mast head. The two cable ends have stay > adjusters. > > There are two single blocks on each side for a total of four, with one of > > which having a becket. Those blocks by the way, are attached to the > > backstay cable with a short piece of cable swaged on to the mainline. > > (Describing it is easier than drawing a picture). I know the blocks are > for > > increasing the tension and adjusting underway. Bottom line, everything > > looks very homemade. > > The last time I asked about this, everyone said to purchase a new > assembly > > with the traveler bar from GB. Does the latest GB version work for a > > traditional mast? Is there a height difference between the IMF mast and > the > > traditional? Or do I just make a copy of what I have? > > Current price of the Backstay assembly is $425 if the webpage prices are > > still accurate. Next email is to Mr Gabriel. > > Thanks all. > > Brian > > NewIn76 >
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