Unstayed mast design software

Stayed mast versus unstayed mast on a small multihull. On a more downtoearth scale, eric hall, coowner of hall spars, has built three unstayed wing mast prototypes for a j90 sportboat. Her carbon fibre mast is 90 feet tall and she carries 1650 ft. Even if many kinds of small sailing boats are fitted with unstayed masts. Puddy tat is a beautiful example of the radical bay 8000 design, a lightweight and competent sailing catamaran that features biplane unstayed carbon masts. We have experience designing and building carbon masts and spars for a. The jib is stored on a manual furler and the mainsail is managed with lazy jacks and a stack pack. I cant imagine how they got them up again, but facts is facts and weston martyr mentions seeing it done. Is there any information available on how to build a large unstayed mast, say to fit a roberts 434.

An unstayed mast also known as a freestanding mast is a type of mast on a boat that is not supported by any stays. Garry hoyt, a champion sailor and noted maverick, created the unstayed rigs to give freedom from the inefficient sail shapes of traditional sloop rigs as well as. The mast height and wing size is scalable to any application, says ott, but for the x2, the designers determined the optimum mast height as 62 ft19m, with a base 18 inches0. Excluding unstayed masts which are predominantly used on vessels under 10 meters. What i didnt take into account was the fact that the yard transfers the entire force of the wind to the masttop where it is connected. She is offered with twin unstayed carbon masts that can be built yourself, or a standard alloy mast is an option. Strong wind downwind in unstayed cat ketches and cat yawls. An important component of the rig was to be a main mast set in a tabernacle, so as to allow quick and easy rigging and unrigging for trailer transport. All selden dinghy mast sections have been designed to give the best stiffness to weight ratio available in.

The polemast, the simplest form of mast, is found on naval ships, including. So, before you start to design the sail you need to check your boat for a suitable position mast, then design the sail plan to suit. It will have a small stayed deck stepped mast from a 17 ft catam. And now, five years later, his aero rig design, with unstayed wishbone mast configuration is ready to present to the industry.

We just got the bids in on the new carbon fiber unstayed mast for alexs khsd 45 catamaran being built in blaine, wa. Hi mike, i live in wellington nz famous for lots of wind and wild water. The mast step where the heel of the mast sits, and the mast partner which the mast passes through at the deck. The junk rig association unstayed aluminum mast expert. This involved writing the computer program that actually designs the fiberglass laminates for. This lively 30footer has proven an excellent benchmark because several sisterships with standard rigs are actively raced in halls neighborhood. A pair of free mast design programs for round wooden masts one to develop strakes for round masts and another to calculate mast size and strength for stayed and unstayed rigs based on sail area and. The main unstayed is around 16 feet tall and folds in half with a 2 foot metal sleeve that slides down from the top portion to sit on the bottom portion of the mast section.

Richard hired me to design masts for his boat made from tapered aluminum tubes which was my first attempt at engineering and design for unstayed masts. After two years of wrestling with the mast and its forestay and shrouds i designed a tabernacle around a mast with a square section for the first four feet or so. On the issue of the masts being undersized, i used mast design software to calculate minimum diameter. Although it is being specifically doctored for mast, it could be adapted for estimating stresses of similar structures. Carlson design goodies gregg carlsons page now includes a pair of free mast design programs for round wooden masts. Would anyone here happen to know a rigging professional who would be familiar with junk rigs and unstayed masts in general.

Unstayed masts downloadable sailboat plans by george whisstock. This model has to be implemented in a fea software, in the present case ansys. When approaching a bridge the crew, these were two person craft, went forward, eased off the fore stay, and pulled the mast down over the hatches. This applies to the mast wall thickness at any height, any diameter. There are scratches on the poles, some seem a bit deep to me and i would love to have an experts opinion on it. Based in the beautiful highlands of scotland with its fantastic west coast sailing, freewing masts manufacture a revolutionary design of aerofoil carbon fibre masts which greatly enhance the pleasure and the safety in sailing. There are four main types of masts, namely, polemasts stayed and unstayed, tripod, lattice, and enclosed masts used on naval ships. Everything lines up perfectly except mast step tube on f5 is a little deeper insignificant still plenty of head room and the step is a tad wider too. A pair of free mast design programs for round wooden masts one to develop strakes for round masts and another to calculate mast size and strength for stayed and unstayed. There was in fact a carbonrigged version of the nonsuch 30, known as the nonsuch 324, but only a handful were built before hinterhoeller folded in 1996. Because of the nature of the rig a junk sail works best on an unstayed mast.

Unstayed masts may provide better aerodynamics but require careful design both as far as the mast itself is concerned and as far as the vessel deck. In taiphun typhoon they would lower their masts and lie ahull until the blow was over. An unstayed mast is a type of mast on a boat that is not supported by any stays. The multis have too much stability, specially the catas with the very peculiar curve of stability, maximal just when one hull leaves the water. Freedom yachts was the maker of the freedom sail and legacy power yacht brands. I have not contacted the owner as i dont have a boat yet i could put them on.

Freedom yachts produced a large number of yachts up to 44 feet with unstayed masts. Commercial software for the analysis of guyed towers, selfsupporting towers, and monopoles is available by contacting guymast inc. Puddy tat schionning biplane sailing catamaran for sale. Aerorigunstayedmastunstayedrigshorthandedperformance. Chinese junks used to have their unstayed masts set in tabernacles and the mast was counter balanced with a heavy weight just like a broads cruiser. Traditional american catboats and dutch fishing vessels ranging up to 60 feet have been built with unstayed wooden masts and recently schooners. I appreciate unstayed masts have done 10,000s of miles and 99. Past attempts at this were specific to a particular boat. An unstayed mast sketch on left is essentially a very simple bit of kit. I was wondering if there are any guidelines on designing unstayed masts. Strong wind downwind in unstayed cat ketches and cat yawls more safety and efficiency december 23, 2019 july 4, 2011 by michael storer in general our thinking about angle of heel downwind is passive however we can take active control also a neat trick for more power from cat ketches and yawls with or without unstayed masts. Working models for analysis and detailed design are provided based on catia v5 cad software. Sailboat mast design, construction and maintenance inspection. Unstayed masts themselves are often somewhat heavier.

Whimbrel was designed with a balance lug mainsail, and to capitalise on some of the advantages of this rig no headsails, no sailtrack or lacing, selfvanging boom, simple and effective reefing the design was drawn with freestanding masts. And with most junk rig conversions the mast will need to be positioned forward of the bermudan mast position. Good sailboat mast design requires that the sailboat shrouds and stays are attached internally, using a developed captive tbar and in mast terminals to cut down the windage created by external tangs and toggles. Unstayed masts set in tabernacles according to alan moore, author of the last days of mast and sail the mast and sail of a norfolk wherry was very quickly lowered and raised. I am no longer in professional practice, and my old company and website, sponberg yacht design inc. Sponberg, retired naval architect, once owner of sponberg yacht design inc. Southern spars makes use of north sails proprietary sail design software, membrain, which allows them to work with real sail shapes during rig design. An optimist, laser or sabot are common smaller examples of a cat rig, but many bigger boats utilize the setup. It is worth noting that boats with more contemporary unstayed wishbone rigs, like the much sleeker wyliecat, have stiffer carbonfiber masts. Guymast is the leader in tower and mast analysis software for the communication and broadcast tower industries. Im costing out building the boat and i just got the quote on the mast, and i dont think my bank manager would approve. Selden has the design expertise and software to enable us to create a mast to.

The software integrates with our own mast design software, rigcalc. Unstayed masts may provide better aerodynamics but require careful design both as far as the mast itself is concerned and as far as the vessel deck and keel design is concerned. The mast is totally unstayed and is mounted in two bearings. I have discovered a couple of unstayed hollow timber masts, 12m and 11m, for sale near here, not sure what boat they came off of. On yacht masts, the spinnaker pole track is positioned on the leading edge of the mast with the boom gooseneck on the trailing edge. The junk rig association unstayed timber masts looking. So, before you start to design the sail you need to check your boat for a suitable position mast, then design. Maybe drop the red herrings and reply to the reasons why unstayed masts are better for cruisers. For unstayed masts, you really need to consider the moment of the boat going downwind and stuffing the bow under in the rig design, not just the heeling force of upwind sailing. Freewing masts unstayed aerofoil carbon fibre masts. The mides touch since mides design s erik sifrer first spoke with in 2009, he has been busy developing his aero sail system.

Unstayed masts are often seen with smaller sailing dinghies such as the optimist and the laser, but can also be used on larger vessels. The aerorig is made up of a mast, a main boom and a foreboom. The total cost of fitting a stayed mast together with the sails, winches and all associated gear is really beyond belief. Not so, the forces on the hull with an unstayed mast are actually lower than for a conventionally stayed mast and cost less to construct. Hull designer, a simple, interactive, visual 3d hull design windows program for modeling and developing panels for hard chine construction. There are two reasons why unstayed masts are uncommon cost handmade carbon fibre construction costs 24 times as much as conventional extrusions conservatism.

The mast step where the heel of the mast sits, and the mast partner which the mast. So, when we design a mast, we have the actual loads and forces generated by the sails and how they deform throughout the. Ultimately, richard was able to get carbon fiber masts designed and built by a california supplier. We are a custom builder of triaxial carbon spars, stayed, unstayed. Actually i just want one of the masts, and a glass boat of 2830 ft to put it on. Scantling of sailing yacht mast and sail deformation. The freedom sailboats have unstayed rigs, meaning that the mast is freestanding and not supported by the normal set of wires called standing rigging.

I use the inside diameter because practically all my designs start with the controlled surface as the inside surface of the mast that is, the masts are laid up over male mandrels. The first develops strakes for round masts, while the second calculates mast size and strength for stayed and unstayed rigs based on sail area and wood types. There is not a whole lot in the literature about the design of unstayed masts. The aerorig is a fusion of a chinese junk rig and modern materials technology, designed by ian howlett. The troublemaker is exceptionally easy to build compared with the multihulls, and estimates are under hours for a complete boat. When developing a sailing boat, the design and scantling of the rigging system. For example given a certain sail area and displacement of the boat. Mastermind pro mast design and analysis system principia. Single main sail with unstayed mast on cruising catamaran. Modelling and analysis capabilities for lightweight masts. Mast tabernacle design here is a video of a john leather designed 17 oyster sloop i built in 1994. A lot of yacht design, and most of our aesthetic appreciation of it, is based on the limits ancient materials so, thinking outside of box for a moment, would there be any advantage to allowing for forestays. An instructional video on how to build a sturdy, affordable, wooden sailboat mast. Weight and efficiency of the main sail are the problems with an unstayed mast on a multi.