Narai With Modern Lug (Junk) Rig

[Budget Boater]

A list of the rigs I have owned:

• Sloop

• Ketch

• Cutter

• Hasler-McLeod Lug (junk) schooner

• Tiki wing sail sloop

Without hesitation, the junk rig was easily my favorite with the ketch rig coming in a very, very distant second. Now I know Wharram's philosophy on the Junk rig and catamarans, and if we were talking about high speed cats, I would certainly agree. However, on a 7 knot cruising catamaran such concerns will not be an issue (and with a family of 6 and all of their crap, I would be overjoyed to make 7 knots.) I normally drove my previous H-M lug rig to over 8 knots on my Colvin Gazelle, and if it can push that big steel 24,000lb hunk at those speeds, it can do similarly with Narai.

I could extoll the virtues of the H-M lug for many pages, but that would get boring. So instead let me highlight the pros and cons:

PROS

• Extremely inexpensive to build and maintain (1/5 of a Tiki Wing Sail rig)

• Simple to home build the entire rig and sails

• No standing rigging

• 30-seconds to put in or shake out any number of reefs

• Small children can operate

• Painless tacks (and accidental jibes) - just push the helm over and the rig does the rest.

• Any sail tears will not extend beyond a single panel and you can still sail with a full tear.

• Wing and Wong (wing) downwind sailing.

CONS

• None (well actually it is a low aspect sail, but so is the Tiki wingsail schooner rig)

This is not going to be a bi-plane rig (with masts in the hulls), but will have masts mounted on deck in tabernacles. This will allow the mast to be easily lowered to the deck for canal and intracoastal waterway work, or for moored hurricane preparation.

Personally, I cannot find what is not to love, especially since this rig will save me lots of time and money.

[Armin Foell]

Hi Budget Boater, this all sounds very well. Could you explain the difference of your H-M Junk rig vs. a traditional Junk Rig? The Junk Rigs I know are very heavy, easy to sail but difficult to handle, not "for Children" definitely.

Do you have a sketch or photo of the H-M Rig?

And why can you built it for only 1/5th of the costs of a Wingsail rig? The wooden mast should cost the same as for a Junk rig and the standing rigging cannot cost 4/5th of the entire rig. The sail will most likely be the same in pricing.

Thanks and regards and always fair winds

Armin

[Budget Boater]

Armin,

I wish I could explain the differences, but I have I never owned a traditional Chinese junk to be able to tell you the differences. However, my H-M junk rig on the Gazelle was quite light as built, especially compared to the other rigs detailed in the plans. My 100lb wife could very easily handle the sails on our Gazelle, from raising to lowering, to shaking reefs in and out during storms. The weight transferred to any line is less than 40lbs, which my pre-teen daughter can pull. Typically the most difficult part is raising the sail; after that, the design allows the sail itself, wind, and gravity to do most of the other work.

During one storm we needed to heave to off the coast to wait for better weather to enter the harbor. We timed my wife putting in the reefs to both sails (four in the fore sail and two in the main), which took her barely over 30 seconds. Shaking them out took her just under a minute. Until you experience it, it is really hard to imagine.

Though the masts are approximately the same cost as a Wingsail schooner, the real savings is the sails themselves. Because of the lower loads imparted upon the material, a junk rig sail can be made of nearly any material (tarps, canvas, cotton, billboard signage, etc.), which can be had for a couple hundred dollars at most and the sails can be built on your living room floor since they are completely flat. The battens can be had for less than $100 and are usually found for free. The branded Tiki 38 sails we just purchased from the loft cost $2500. This is before adding in the cost savings from the elimination of standing rigging.

Put in a more simplified way: A junk rig can actually be made from junk and still preform quite well, whereas a Tiki Wingsail rig cannot. The junk rig allows for building or repairs from whatever materials are locally available.

The best place to learn about the H-M lug is their book "Practical Junk Rig."

Armin Foell said:

Hi Budget Boater, this all sounds very well. Could you explain the difference of your H-M Junk rig vs. a traditional Junk Rig? The Junk Rigs I know are very heavy, easy to sail but difficult to handle, not "for Children" definitely.

Do you have a sketch or photo of the H-M Rig?

And why can you built it for only 1/5th of the costs of a Wingsail rig? The wooden mast should cost the same as for a Junk rig and the standing rigging cannot cost 4/5th of the entire rig. The sail will most likely be the same in pricing.

Thanks and regards and always fair winds

Armin

[Andrés]

Hi, are you going to put a mast on deck in a tabernacle without standing rigging?

[Budget Boater]

Yes, though I may install running backstays (of braided line) through blocks if necessary. I do expect the tabernacle to be quite tall, in the 6-8' range.

Andrés said:

Hi, are you going to put a mast on deck in a tabernacle without standing rigging?

[Andrés]

It is an interesting approach. I have never seen a free standing rig that it is not supported in a keel. Perhaps you should reinforce the beams or install a dolphin striker, because I suppose the mast creates a lot of compression in its basis.

[Armin Foell]

The compression on the beams caused by the mast will be most likely less compared to a design with stays and shrouds.

In a "traditional" rig layout you have to consider that the load of the shroud tension adds to the weight of the mast! This can be easily 2 or 3 times more than the mast weight. Even if you built a free standing mast more solid than a shroud/stay supported mast, the overall load will hardly be more than "ususal"

Regards and always fair winds for all of you

Armin

[Budget Boater]

It will not apply any more force than a Tiki Wingsail rig, and that does not have dolphin strikers. The trick to an unsupported mast is to engineer it to bend and flex, especially at the top. This is why most junk rigs have tapered masts. The beauty of the H-M rig is the way the top of the sail bleeds off power in wind gusts. This along with the flexing mast lowers the overall force applied to the base and tabernacle.

Andrés said:

It is an interesting approach. I have never seen a free standing rig that it is not supported in a keel. Perhaps you should reinforce the beams or install a dolphin striker, because I suppose the mast creates a lot of compression in its basis.

[Andrés]

I was thinking in my Tiki 26 that has a dolphin striker, but now I see that the Tiki 38 thats not has it, but has the tabernacle supported between the two first beams. I've never been in a junk rig boat, but i like very much this type of rig for it's simplicity and versatility. I've seen that I didn't express well, but I was thinking about all the forces acting in the basis of the mast (compression, lateral and fore and aft forces), in a mast without standing rigging. But you say that the forces are low, so may be I am mistaken.

Regards. Andrés.

[Jeremy Walker]

Just another idea to toss into this discussion.........because I have some experience with fully battened lug sails but have headed away from any un-stayed configurations.......................how about a bipod mast which rakes aft and uses a wire led vertically as a combination backstay and batten track. There will be a forestay as well to support the rig structure in 4 directions.

Sure this means using a jib as well ( with attendant sail handling demands or cost of rollerfurling), which is pretty much a sail type that all catamarans benefit from. But at least leans a little toward performance at the same time as being economical.

My understanding of a freestanding mast is that it is either heavy or expensive. So to save cost and be fully supported by a tabernacle structure built upon the hulls connecting beams, weight or cost is going to climb further than any H/M junk configuration...............those guys pretty much built their rig philosophy on deep keel configuration.

[Ricardo Aráoz]

The mast beam will absorb the lateral components of the sail forces. But what will you do with the fore and aft components? They will tend to twist the beam, will you support the mast beam on the forward beam?

Budget Boater said:

It will not apply any more force than a Tiki Wingsail rig, and that does not have dolphin strikers. The trick to an unsupported mast is to engineer it to bend and flex, especially at the top. This is why most junk rigs have tapered masts. The beauty of the H-M rig is the way the top of the sail bleeds off power in wind gusts. This along with the flexing mast lowers the overall force applied to the base and tabernacle.

Andrés said:

It is an interesting approach. I have never seen a free standing rig that it is not supported in a keel. Perhaps you should reinforce the beams or install a dolphin striker, because I suppose the mast creates a lot of compression in its basis.

[Budget Boater]

Typically on a junk rig, the masts lean forward. This is to allow the offset sail to self-tend - a major advantage of the rig. It also allows for movement of CE to reduce weather helm. Worst case, you keep the masts plumb. Regardless of rake, as soon as you start adding non-moving standing rigging you lose the ability to project the sail on all points. This is why running backstays (especially on a catamaran) on forward raked mast can help support the mast in all directions and not get in the way since you ease the leeward stay when necessary. (The stays are run aft and out to the gunnels at generous angles, and turn through blocks that run the line aft to a cleat, which allows the leeward stay to be eased for sail clearance.)

On my Gazelle, the tapered aluminum masts (made with commonly available light poles) were stepped on the keel. They were completely unsupported where they passed through the deck. Even during storms they never touched the deck when flexing. From the base of the mast to where the foot of the sail started, it was about 10' (3.2m). So the force imparted on the keel stepped mast occurred very high. On a catamaran, it is possible to have the foot of the sail start much lower to the base of the mast, thereby exerting much less force on the structure.

The first time I saw a deck stepped junk rig was on an engineless 65' plywood sharpie. It was a triple masted junk set in tabernacles mounted on moderately reinforced plywood decks (extremely light deck structure compared to Narai or Tiki beam.) The owner used the boat exclusively to make runs between the Florida Keys and Honduras to deliver aid (and pick up the next bride to be) without ever experiencing any structural issues. He claimed to sail at 10-12 knots most of the time, especially on the unloaded return trips.

Based on my initial calculations, the masts will not sit directly on the beams, but will reside in tabernacle mast cases. The foresail will be forward of beam one, which will necessitate the addition of a support beam near the bows. The mainsail will be just aft of midships, supported between beams two and three. Because the masts will not directly be supported on any one beam, but in mast cases connected to two beams, the for/aft twisting forces imparted on the beams will be negated. Since I will be using tapered masts, these are designed to take the full load without additional support, I will only need to engineer the mast case tabernacle to spread out the force of the mast step.

[Jeremy Walker]

A sharpie or most any other monohull will heel easily enough to reduce sideways loads at the upper mast support area, Pitching will not load up the mast partners as much and because the forces are in a forwards direction the multipart sheeting system acts to lend support from behind.

In contrast a V hull sectioned catamaran has a very quick motion (compared to a monohull) and is going to load up the mast tabernacles a bit more than was the case with the sharpie. Structure to cope with this loading is going to cost a lot or weigh a lot more than rigging. Then again it all depends on where the craft sails and what stresses are imposed on the mast, so pottering between leeward Islands in fine weather is never going to be a problem.......if that amounts to full usage of the craft.

When the craft has to cope with violent pitching moment where it is brought to a full stop on meeting steep seas head on, then a tall forward raking mast in the bows is a liability hardly worth the risk. Whereas a mast with aft rake and back staying will carry much of the loading axially, rather than bending like a whip.