Standing rigging is the collective term for the system of wires (or rods) that supports the mast, both fore-and-aft and laterally. On a boat like yours with single uppers and double lowers, the uppers see about 45% of the load and . Perform routine cleaning/polishing to remove corrosives, identify chafe points and other damage, and properly tune your standing rigging (shrouds, forestay, backstay). In addition to acting as a support for the mast in general, it allows you to decrease forestay sag without adding compression to the mast. I don't have a direct figure for RM30 but I do have IMS measurement data for the 10M and can extrapolate a pretty good approximation. We had no doubts having already simulated the effort with checkstays. To reduce the bend we had to reduce tension of the V1s but also monitor the tension of the D1s. Differences emerged immediately, the D1 on the left was about 1cm shorter than the one on the right. I could measure the rake with a bucket, but I had somewhat of a historical memory of the setting of that mast. Unstep the mast and remove the rigging from the boat. However we had to make some assumption and one was that each pair of shrouds would be the same length. Running Rigging Calculator - SailboatOwners.com These work laterally to support the mast. Others, such as Mr. E.Sponberg, make other distribution of forces. Condition of sling - passes all inspection criteria. Establish the thread size, type and directionWire terminals that have a thread for connecting to the next component are known as studs.Stud terminals are denoted first by the wire diameter and then the thread type and size because each wire diameter can have more than one thread option.The thread options are generally referred to as downsize, standard and upsize - these are broadly categorised in the same way by all the manufacturers.UNF thread is the most common in the UK, but Metric is always a possibility - bear in mind that the yacht or the mast may have originally been built in Europe where metric threads are more prevalent.Stud terminals are normally Right Hand thread but it is worth checking, especially if they are metric thread on a French built mast. Maybe I was being a bit hyperbolic when i said that dude was 3x the amount of competitors. RIMAST - Masts and Riggins Calculations Replacing Your Standing Rigging - RIGWORKS INC. Swaged terminals are manufactured using 1 or more of the 4 processes listed above. We always look forward to seeing you! It is important to use a tape measure under tension and that does not stretch. It is important to do this while the mast is still up and set for normal sailing as this will be the base line to produce your new rigging. I need to do some more study and number crunching. Their role is to prevent the mast from bending to leeward between the first and second spreader levels, especially upwind. When measuring rigging, the convention is to measure from pin center to pin center or from bearing point to bearing point. I therefore decided to tighten further the D1s by a turn and the D2s by two. T-terminal is a generic term for all the different forms of shroud attachment favoured by mast manufacturers, both current and historic - T, T-Bar, Flathead, T-Ball, Stemball, also known as Elephants Foot, Stemball with Cup, Spoon and Shroud terminalare all variations on this theme. The overall shroud load is divided up between your shrouds. I have a ketch with 1/4" SS on the main and 3/16" on the Mizzen. You're right (I need to think about). We would be happy to loan you a tagline (strong and thin) to use as a place holder, or we are always happy to visit your boat and tag it out for you. And yet I have read that once stretched to its working load, regular Dyneema will stabilize and then experience even less creep than DUX. How do I calculate righting moment? - Sailing Magazine Required fields are marked *. We do support educated do-it-yourself sailors if you are confident and understand the rigging process. A rig inspection beforehand can minimize surprises. RM30 is the force that is required to heel the boat over 30 degrees. We are ruling this one out for us. We are confident that you will look forward to our emails. For the Main Im thinking 12mm (larger than either the Colligo and Rigging Doctor calculations) and the largest size of Liros D-Pro-XTR available). The Supajust Eye Toggleand Swage (bottom) is a high specification stainless steel open body turnbuckle. Braided line density is the key to eliminating constructional elongation over time. Asymmetric Spinnaker Sheet - Boat length x 2.5 to 3. The Lift-All Sling/Leg Length Calculator has been designed to assist you in selecting the appropriate size slings for your lifting applications. Raise then the equations of equilibrium will be more easy task. Then we choose what percentage of the breaking strength of the Dyneema we want this to be. Keeping your existing turnbucklesCheck the thread type (UNF or Metric) the thread size (standard or upsize)and, just to make sure, the thread direction. Dynice Dux or SK75 - RIGWORKS INC. T-terminal and some have more than one common name, but this guide will help you to recognise which ones are correct for your rigging. The list of materials and design stresses are those that ISO 12215-5 standard says that can be used. I.e. Our calculator is easy and simple to use. These additions add up quickly and affect the cost of parts, labor, special order shipping, taxes, etc. Tapped and Formed:Some Swage and Swageless terminals are made of several components.These partsmay be tapped together like the strap toggles below. We highly recommend you hire a professional rigger if you are not familiar with this process. With this expedient you can shorten the checkstay relative to the runner to the point that you set the checkstay and the runner remains effectively loose. If you are replacing your turnbuckles, make sure the existing turnbuckles are adjusted to their normal set position for sailing before taking your measurements. Herb suggests under 15% or even better under 10%. Catalina 22 Shroud Sizing | SailNet Community Confirm Hole Diameters and Pin SizesIt is critical to the load bearing capacity of the rig that the holes and clevis pins are closely matched together without any play.Ordering terminals with pins that are too large fortheir allotted holes onboard will either mean some awkwarddrilling/reaming or starting the ordering process again.N.B. Plus there will be more spare strength if there is UV or Chafe damage. For example, assume a 2,000 pound load is to be supported by 2 legs of a sling. We use the highest quality standing rigging components available, and we won . I have to study the correct way to approach this problem. A high-performance racer might require a lighter, stronger, lower stretch (i.e. With a bent mast the first thing really is to understand was why it is so. Standing rigging Definition & Meaning | Dictionary.com Question: My halyard is binding. First of all, the mast was not straight, it pulled to the left until the first set of spreaders. This type of rig is fitted with a runner at the mast top and a checkstay at the height of the inner forestay. First, we multiply the load by 1.5 to approximate the rest of the righting moment beyond 30 degrees, and divide by half of your 10-foot beam. We will talk here specifically about boats with swept back spreaders. This is a very inexpensive investment (by yachting standards ) to ensure that your rig is in sound condition. [End Update]. The numbers in the Toss and Henderson calculations were for a 2.5 safety factor. We also attached spinnaker halyards one to the left and one to starboard to an eyebolt. As a quick side note people often ask if they should switch from rod to wire rigging or vice versa during the re-rig (usually from rod to wire as rod is much more expensive per foot). Marlow recommend one thing, Colligo another, they both swear by the logic! [Update]See the first comment below from John Franta, Colligo Marine where he explains the difference between heat stretching at Fibre level (SK78 and SK99) vs at the Braided level (SK75). This system with T-bone on the checkstay give you maximum flexibility and is obviously suitable for those who know how to use it. So we can put back the T-bone that shortens checkstay and use it as a counter cable for the inner forestay. The swept back spreaders ensure that the mast can stand up even without the backstay, which is no longer structural. In this case the forestay does not reach the masthead but only up to seven eighths or nine tenths of the mast height and so do the attachments of the shrouds. Member Album by TANSL | Boat Design Net https://www.boatdesign.net/gallery/albums/member-album-by-tansl.4186/, TANsl https://www.boatscantling-iso-12215.net/, (You must log in or sign up to reply here.). The boom will rise again when we tension the reef line and this rarely even needs the boom to be helped by hand. Unlike the Gerr formula the RM30 formula accounts for shroud base width. For example, low stretch is very important in a halyard but not necessarily in a sheet. And if in doubt, too long is always better than too short! The curve to starboard between the first and second set of spreaders was attributable to the upper diagonal D2 on the starboard side, which was tighter than the left one. Lift-All Sling Length Calculator Agreement | Lift-All Seen from the side, the mast showed excessive rake and pre-bend that needed correcting. They show up on your doorstep ready to use. special care should be taken to ensure that there will be sufficient material left on the tang/eye/plate if youintend toenlarge any holes. Contrary to popular thought, a slack rig is more punishing on a hull than a properly adjusted, tight rig. Check the thread type (UNF or Metric) the thread size (standard or upsize) and, just to make sure, the thread direction. At the same time, by vertical compression of the mast, tensioning the backstay causes a bending of the mast that flattens the main. Not forgetting the compression loads from the stays too. Forged:Some Petersen Stainless terminals are manufactured using a process known as electrical upset forging.The electrical current used internally aligns the grain structure of the stainless steel.The result is a stronger, lighter fitting that is also more resistant to loading fatigue.The picture shows a machined eye (top) which is slightly larger than the relatively minimal forged eye (bottom) for the same size wire. Write down the number and move on to the next stay. Lets consider the mast of a Class40, with two orders of swept back spreaders and its standing rigging. The wire is inserted into the hollow terminal and pulled through a set of roller dies. Despite the absence of a backstay its not runners or checkstays that keep the mast up. Make sure your turnbuckle is centered between the studs for accurate measurement. The inner forstay and the staysail come up in about 16 knots of wind. They replace the topping lift and support the boom. This is possible because the rod shroud is free to rotate inside its T-Cup at the spreader. Illustrations from left to right below:Bluewave Hook Terminal, Hasselfors Flathead, Hamma spoon, Petersen shroud terminal, OS/BSI T-terminal, Sta-Lok T-terminal and Navtec T-terminal (now discontinued). To preserve the left-right adjustment symmetry, we unscrewed the V1s turnbuckles two full turns each side.