Home Port; on the Delaware River at Fox Grove Marina Essington PA.

Ul-la Lug/Junk Rig Conversion

April 2016

March 2016

Mast raised

Outboard installed

Additional grommets punched in sail head (yard edge)

New boom and yard fabricated;

1 1/2" PVC schedule 40 pipe with 1" x 1 1/2" cedar insert set in epoxy.

1 1/2" cedar insert ripped from cedar deck board , edges eased.

Clear PVC cleaner/primer and glue, end caps and union.

Pipe sections glued, extra length at one end for epoxy pour.

Cedar insert to end of pipe at other end.

End cap glued in place.

PVC Schedule 40 properties
Flexural Modulus, psi @ 73°F 360,000 ASTM D790

Western Red Cedar #2 @ 19% moisture content
Modulus of elasticity psi 800,000

Coal Tar Epoxy
Tensile Strength                                  ASTM D638                    3,600 psi
Elongation at break                            ASTM D638                     28%
Flexural Strength                               ASTM D790                     4,000 psi

July 2012

Next sail, also full batten balanced lug

May 2015
Ulla Gaff Rig with headsail on Bowsprit.
I will conclude my balanced lug experiment this year and begin work on a gaff sail in 2016

April 2015

Chain Bobstay installed (plastic coated chain from an anchor) April 19. Underload the mast rakes back about 1.5 deg pulling the bobstay into tension. The bobstay will also act as a cushion for the too often occasions when I hit the dock.

April 18

Friday April 17: Mast pivot drilled to 5/8" for copper pipe bushing (1/2" bolt fits in 5/8" OD pipe)
Surface prepared for bowsprit.

Bobstay eye

Bow Sprit

March 2015

Preliminary batten layout.

December 2014

November 2014
Removed winch from former mast and will mount on cabin top near companionway for yard halyard. I will also need longer halyard, I currently haul and secure at base of mast.

Halyard Winch cleaned, simple double ratchet operation.

Halyard winch assembled

August 2014
Come back later for a cleaned up page.

Parrels added to battens.
Single line lazy jack moved to mid-boom
Topping lift to be added to boom end to block at mast base then to cockpit cleat.
50mm triple block for yard halyard added to mast top (was 40mm double block)
50mm double block for yard halyard added to yard (was 40mm single block)

Mainsheet moved to former backstay pushpit ring, double-double block.

Boom cockpit clearance adjusted for bimini and bimini installed

PVC wear pad on steel tabernacle to minimize wear on boom, to be secured better.

Tack vang tensioned to slope boom about 5 deg;

Initial design was junk rig with unstayed or stayed mast, but evolved through full battened Balanced Lug to Balanced Lug without battens then with full battens. The lug/junk sail is just a frugal wing sail, old is new again.

Full batten balanced lug sail installed.
Need to add topping lift and lazy jacks.

Yard and boom lateral stiffener added, battens added.
Using GoPro so some fish eye lense distortion.

Battens ripped from cedar deck boards,one coat spar varnish

Next iteration will be bowsprit with jib on Alado roller furler and full batten balanced lug.

Full sail
First reef
Storm/riding sail
Second reef

Balanced lug rig. Still some adjusting to lazy jacks and reefing, but ready for summer.

Steel tabernacle/compression post

September 2013
No more contemplating and procrastinating under the excuse of planing,  it this now a must do before the spring.

The boat will be in Margate NJ for at least 2 months in summer 2014. As is the Bermuda rig at approximately 28'0" will fit under the Ocean City NJ bridge 35'0" clearance, but not the Longport NJ bridge at approximately 25'0" (20'0" during repair work due to be completed before the end of 2013).

Longport inlet which also serves Ocean City has an entrance channel depth at low tide of 16'0" but to get to Margate with Bermuda rig I must go under the Ocean City bridge to a narrow channel through the salt marsh almost to the mainland then down another narrow channel through salt marsh to Margate, about 8 nm.

With the balance lug as designed I will have 20'0" with 1st reef or 23'0" without reef, enough for the Longport bridge which will make Margate only 2 nm from the inlet.

The mast dutch tabernacle will also open up more options on the NJ Intercoastal Waterway and DelMarVa back-bays.

So haul-out this winter will include the rig change and interior upgrades for more comfort.

A Junk sail may be a future iteration?

Dutch Tabernacle compression post

Mast tabernacle hatch infill rough with steel scrap from tabernacle.
March 2014
Hatch infill/mast partner rough fit.
March 2014

 4x4 cedar mast in dutch tabernacle
16ft 4x4 cedar mast, next original mast to be lowered.

April 11, 2014 mast removed, 
winched down using halyard from top of old mast to top of
new mast

April 11, 2014 dutch tabernacle

Lug sail

Reefed sail

KISS option with simple unstayed tabernacle
and simple sail without battens.

Checked with my lumber supplier for quote and delivery. The mast 16ft above deck will be western red ceder for better dimensional stability, with boiled linseed oil finish.
February 2014 mast ordered.

Tabernacle/Compression Post
The mast will sit in an 8ft,  4x4x3/8 steel tube tabernacle/compression post, secured at fore peak step bulkhead and hatch solid infill.

June 2013
Back to work on this June 2013, two weeks of thunderstorms has cut into sailing time.
Tabernacle post was 3/8" steel square tube salvaged from a building I was working on, the contractor did the initial cutting and drilling holes. This week to lighten the tube I removed steel below the forward pivot and ground edges. More grinding and descaling then a bare metal primer.

The mast will swing within the 4x4 steel tube on a 1/2" galvanized steel bolt, and be secured laterally by tube side walls and fore/aft with high and low 1/2" galvanized steel bolts.

July 3, 2013
Grinding, cutting, sanding and wire brush rust and scale complete. Coal Tar Epoxy surface priming on the first almost dry day for three weeks.

Compression Post/Tabernacle
4x4x3/8 steel tube
weight 8 x 18.84 lbs x 0.75 = 113.04 lbs

(1/4 of material removed in fabrication)

The tabernacle/compression post provides for ease of lowering the mast.

Other options that were explored; deck stepped tabernacle with stays. full bury fixed mast with and without stays.

A number of sail options were explored; fabrics, DIY, sail maker and non-traditional sources.

-Dacron with battens, a superior product would be a budget killer, not completely ruled out.
-DIY Tarp, the lowest cost option, maybe good for testing sail shape and patterns but a short in service life.
-Custom tarp, lower cost and probably superior craftsmanship than DIY but short service life.
-UV treated cotton/canvas "tarp" sail without battens, custom or DIY lower cost than Dacron, long service life, but heavier.
-UV treated synthetic "marine awning" material custom made with reinforced edges and reinforced grommets, higher cost than tarp options, but less than half the cost of Dacron, with a service life equal to or greater than Dacron. The main disadvantage over Dacron will be a potential for stretch and shape deformation.
February 2014 sail ordered.

Simple sail without battens,
170 sf = 19 yds @ 9 oz/yd = 170 oz = 11 lbs.

KISS sail                 11 lbs (5 kg)        original sail approx 10 lbs
Unstayed mast       46 lbs (21 kg)      original 24ft aluminum mast approx 75 lbs
Yard                        10 lbs (5 kg)
Boom                       15 lbs (7 kg)     original 10ft aluminum boom approx 25 lbs
Steel tabernacle      113 lbs (51 kg)

Total prelim          195 lbs (89 kg)     Total original approx 110 lbs (50kg)
(assuming standing and running rigging no weight change)
Additional weight 85 lbs but lower including 56 lbs below deck

Spinnaker for downwind running/reach
Jib blade on spinnaker halyard for close hauled
Boom, sheet end
Boom, downhaul end
Boom/mast Parrel
Yard/Mast parrel and Yard Halyard

Partner and Mast Step


Blade Jib
Standing Lug on Loch Broom


Options explored;

Full Batten Balanced Lug Rig with unstayed tabernacle mast

Sail plan stayed mast with Dutch tabernacle
Full batten lug (Junk) sail 190 sf.

Original Bermuda Rig

Main 111sqft (10sq meter) + Jib 74.4 sq ft (6.7 sq meter)=185 sq ft (16.7 sq meter)


  1. HI, Fun to see someone try a new approach for this giant little sailer.Years ago I sailed and owned the # 666 Havsfidra.
    It was undercanvasd unless it really got some wind. I seldom sailed without the large genua hoisted. Often the "cast iron genua" was used.. (VP MD1b).
    New (brownish) sails was bought from Lee Sails in Hong Kong. Lee Sails later made me lug sails for a later smaller boat.
    Lug sails are not hight techs and can't beat a modern rig in a fight close to wind. But in all other directions the lug rigged will not slip after or even, in som directions be winner. The lower center of gravity is a good feature as is the simplicity IF one let it be a KISS rig. There is not much to gain in over engineering a lug rig. Something one maybe should borrow from the Chinese junk sail is not the battens but the rope between mast and sail. Lowering the sail when the wind is still strong is then greatly simplified. I would, having had the simpler set up, trade any losses due to less favourable aerodynamics,
    for greater handiness. As we all know: If you have to beat against the wind your goal is wrong.
    The name, when spelled and pronounces "Ulla", is a common girl name in Sweden.
    Nice reading about her.
    Dejan Petrovic

  2. Hi there!
    Interesting read!
    I'm thinking about how to do a junk rig conversion of a Storfidra (big sister of a Havsfidra). I guess I would do it about the same way as you have, although I rather like the idea of having the actual mast going all the way down to the keel, or at least inside the boat. Also, I think I would try to find some kind of lamp post, like Roger Taylor did on his recent conversion (see youtube!).

    Best regards,
    Mikael, also Sweden

    1. The Storfidra is a larger boat than the Havsfidra, so more sail area probably means taller and stiffer mast. This could be done with a swing tabernacle but a fixed unstayed mast secured at partner and keel would probably be better. As a swing tabernacle with the larger loads from a larger sail area the mast cross section and depth of "bury" in the tabernacle grow larger.

      I arrived at mast height starting with boom length and yard rake, projecting sail area into this limit which gave me a minimum height for mast. The length of mast then determined desirable cross section and material options. Solid cedar was lighter than a similar aluminum hollow cross section, also cheaper and available.

      I would suggest drawing a junk sail of the same sail area as your current main and headsail, locate the center of effort of the junk sail slightly forward of the boats center of gravity. Mast location will be a function of available space below but should be forward of the current mast location.

      I added mast rake for aesthetic reasons, but mast rake can also be used to move the sail center of effort to the desired location. Sail center of effort location can also be manipulated by location and tension in the mast parrels, and tack downhaul/vang. My sail center of effort can be manipulated within a range of 20 cm (8 inches) to 40 cm (16 inches) forward of the boat center of gravity.

      The Havsfidra was originally built with a lifting ring under the sole secured to the keel/ballast for a balanced crane lift, this is the boat center of gravity.

      My design is for a balanced lug but as I experiment this summer, junk sail battens may be added. The current issue I have with my new rig is a tendency for the sail forward of the mast to back-wind in gusts, so far I have been adjusting the yard parrel and downhaul/vang with limited success on the reducing back-winding.

      I do need to adjust the tension in the lazy jacks/ topping lift for better sail control, but so far it sails well to within 30 degrees of the wind, and is well balanced for sailing in steady winds without touching the tiller.

  3. very, very interesting…
    …did you already speak with sebastian from http://tuchwerkstatt.de/product/junksails.html – he's an expert when it comes to junk rigs…
    just sayin'.

  4. So, what's the latest...? I'm trying to modify a 22'6" steel(3mm) Roberts designed Spray...and your vessel is about the same length...Though I wouldn't be burying the Tabernacle so deep into the forward berth area...Just re-enforcing the under deck support area...retaining the forward berths openness...The front of the cabin stands approx 10" above the deck in a vertical and rounded configuration...I was thinking of extending the tabernacle up from it about 3 to 4 ft and braced externally for extra rigidity...

    I'm interested in how yours performed for you....ease of operation and deck walk around .

    1. Spring is almost here and March work will include installing the headsail alado roller furler, making stronger lighter yard and boom, changing to a wire topping lift, and wire shrouds. The rig performed well on my trip last year down the Chesapeake to the Choptank and this year I will be going to Tangier Sound.

      With a steel boat you may have more options to reinforce the deck under the tabernacle, but the advantage of a long bury is a reduction in the bending moment at the deck. Not having a long bury will result in an increased bending moment and compression load at the deck. Stiffening the deck may provide enough stiffness for the bending moment but the compression load will require either a post or portal frame to transfer the load to the keel or keelson. All very doable with steel, more complicated with fiberglass.

      The bending moment can also be reduced with use of shrouds and stays, I use shrouds due to greater flex in my 4x4 cedar post than a larger section cedar post or an aluminum tube. Shrouds reduce the option for a windvaning of the lug or junk sail.

      Still investigating a kort nozzle but it looks like no real advantage for me.



Ulladh pronounced "ul-la" (null lad).

Uladh the gaelic spelling for the territory of the U-Nail chieftains in the ancient Irish province of Ulster (English/Norse), originally the counties of Down and Antrim, but now including Derry, Armagh, Tyrone, Fermanagh, Donegal, Cavan and Monaghan, also referred to as Ulidia (Greek/Roman),.

Uladh was the home of a pre-celtic, cruithne (crew-en-ya) pictish tribe, who may have been descendants of prehistoric tribes indigenous to the British Isles since the retreat of the last ice age.

Archeological finds date first inhabitants to about 6,000 BC and trade goods from Rathlin Island, County Antrim off the northeast coast of Ireland made from porcellanite stone appearing in Egypt and Crete by 2,500 BC.

The early tribes of Ireland where displaced by later waves of migrants from mainland Europe; about 1700 BC by bronze age tribes, celtic tribes about 500 BC, and in the past two millenia; Roman trading posts, Viking settlements, English plantations... and in the 21st century a welcome increasing diversity from the European Union and the world.

SV Ulladh (for vhf clarity I use "sailing vessel ul-la") is named for the territory of the first peoples to settle in Ireland after the retreat of the last ice age.


Since 1949 Fisksatra Varv in the coastal town of Fisksatra Sweden, built fiberglass boats from dinghies to a 300 ton minesweeper for the Swedish Navy.

The Havsfidra 20's were built between 1968 and the late 1970's to Swedish Navy and Lloyd's certification standards.

The Havsfidra 20 and a larger version the Storfidra 26 where sold in the United States by Continental Yachts and Trawler Agency of Atlantic City NJ.

Havsfidra; sea-feather?
(fidra; to touch or tickle with a feather -Icelandic-English Dictionary, Clarendon Press 1874)