WIKI for setting up and tuning Lug and Sprit Rigs

Mark Sailing His Goat Island Skiff at Barton Week

This page is a work in progress and will eventually be transferred to a WIKI.

Also be aware that since it was published we have started making sails. Please see reallysimplesails.com for excellent sails at modest cost.

Lug Setup and Tuning on this website

We have probably done more writing, explanation and photos than any other place on the net about lug rigs and their setup.

Click this link for a comprehensive list of articles on Lug Setup and Tuning.

You can also visit the website for the Oz Goose sailboat for more Lug Rig information. We are racing them regularly, so there have been a lot of lessons there as well.

Overview

This is a document we are gradually adding to as more information becomes available.

It is useful for the setting up of balance lugs, lateens and some sections are useful for standing lugs.

Lug and sprit rigs have been thought of as antiquated and low performance.  Over the last years we have found that most of the perceived lack of performance was because they were allied with poorly set up boats.  I made a start at collecting useful rigging information here.

We have found that most of the lessons of modern raceboats are directly applicable to the traditional rigs to give them very close to the same performance – but in general it can be achieved at a fraction of the cost of a modern racing rig.

There are a bunch of updates from 2013 on my website.

Lug rig setup 2013 – lessons learned – use of a vanghaul and bleater

Lessons from racing a BETH sailing canoe with a weekly race fleet

Lessons from sailing a Goat Island Skiff with a weekly race fleet

Lug Rig and Sail Twist – General

The great thing about balance lug rigs (Blue boat above) and sprit boom rigs (yellow boat below) is that the twist is controlled reasonably effectively but with a minimum cost of extra gear – unlike the modern rig that has to be fitted with a separate boom vang.  The pic above is the first sail … Perttu started really tightening the downhaul after this and his sail is much less twisted now.

The most important single sail control on a balance lug rig is the downhaul.

Modern raceboats get a large part of their performance by controlling the twist in the sail. So traditional rigs also get a boost from the same tech.

The picture of the blue boat above shows Perttu creaming along in his newly launched PDRacer last year.

Basically the downhaul must be very tight in all conditions except for very light winds.  In stronger winds as in the pic, you need to be brutal.  We find a 3 to 1 purchase is OK for the 8ft PDRacer, but the 16ft Goat Island skiff needs 5 or 6 to one. In stronger winds the tension needs to be brutal.

Perttu trims his downhaul nice and tight all the time now, so can be excused for not getting it right on his maiden sail.

Lug Rig and Spar Bend – General

With a lug rig the mast bend is not critical as in rigs where the mainsail attaches along the length of the mast.  The most important factor is that the mast is not TOOOO bendy otherwise the distance between the top and bottom reduces and the halyard will slack off.  The amount of bend for the halyard to be slacked off too much is quite noticeable.

One of the most highly developed lug rigs is Brad Hickmans on his PDRacer (based very stongly on the OZRacer)  that won the 2011 “Worlds”.

This is an idea of the lateral bend with the boat fully powered up … it’s Brad. Then some calc results by Ian Howlett after.

This photo was taken by Kevin Hahn at the 2011 Worlds. I’ve enlarged it to the point it’s not very clear but you can get an idea of how much my OzRacer (formerly OZ PDR) mast flexes with gusts in the mid 20 mph range. the bottom 12′ of the mast is 2.5″ OD and the upper 1.5′ is 2.25″ OD, both are 0.065″ wall 6061-T6.

From Ian

OK, some rough numbers:

A solid round wooden mast of Oregon or similar 62 mm diameter at the base will have a stiffness of about 9 kNm^2.

Mik’s 62 mm hollow square section with 12 mm wall in wood will have a stiffness of about 13 kNm^2

The 2.5 inch outside diameter 6061T6 aluminium section with 0.065 in wall will have a stiffness of about 10 kNm^2.

Don’t worry too much about this kiloNewtonthingimy business, what it tells us is your Alu mast will be a little stiffer than a round wooden stick, but not as stiff as Mik’s hollow square mast.

If I compare ultimate bending strengths of the two masts, your alu mast looks a little weak.

If I convert to something easier to understand, if we were to put the PDR on it’s side with the mast in place, and compare how much weight we could hang off each mast one metre above the partner:

Your alu mast would likely break at the partner with 136 kg hung one metre from the partner.

Mik’s hollow square mast could take about twice as much before it breaks.

So, if you are 220 lb or more with long legs and the abs and the motivation to hike out to the max going to windward in a near gale, you might come close to breaking your aluminum mast, if you are not so heavy, or don’t hike quite that hard, you should be OK.

Weight comparison:

The aluminum section is about 40% lighter than the solid wood one, but fairly close in weight to the hollow wood square section.

Hope this helps, I’ll run the numbers through for the smaller 2.25 in OD/0.065 in wall alu section when I get the chance.

Ian

PS: Detail for the technically minded:

I got specs on the alu from here. Elastic Modulus of 69 GPa, modulus of rupture of 276 MPa

I based the wood calculations on an E of 13 GPa and a modulus of rupture of 80 MPa”

Lug Rig and Sail Settings – General

Those who collected or made this information available

(please use text but format it as a link – eg below – use your forum name or whatever you want to use on this WIKI and when the proper wiki is used we will have links from your names to the blog eventually)

Boatmik – storer boat plans latest – storerboats website – storerboatplans forum

Woodeneye – Goat Island Skiff Blog – Building a GIS on woodwork forums

Brad Hickman

Bobwes

Christophe

Pauli

Bruce

WarmBeer

Ian Howick

Brian Pearson

George Isted

Dave LaFontaine

And others!

Lug Rig and Sail Twist – Goat Island Skiff

The standard downhaul has to be used well to control sail twist.  The general rules are that for a little boat like a PDR the downhaul needs to be at least 3:1 and more powerful boats like the Goat, around the 6:1 mark.

In very light winds – too light for the boat to move reliably the downhaul can be slack to allow the sail to twist.  As soon as the boat starts moving reliably the downhaul must be firm.  When starting to lean out it needs to be tight.  As the boat becomes overpowered it should have BRUTAL tension.

Some have been fitting a boom vang and moving the downhaul slightly forward on the boom.  The designer doesn’t like the complication and feels that the simple approach is better, but doesn’t want to discourage experimentation to improve performance for those who want to seek it.  So we will add more information about vanging here eventually.  Acknowledgement to Brian Pearson who sails balance lug rigged Lymington Scows in the UK for starting this line of enquiry.  The Scows have had at least 100 years of competitive development and probably have the most highly developed balance lug rigs in existence. Brian’s is one of the best in that group – he won the championships this year too!

We have discussions on my forum of Brian’s material on vanging and setup of racing balance lug rigs.

Lug Rig Heaven

Lug rig heaven 2010

Lug Rig Stats & Spar Bend – Goat Island Skiff

One extremely paradoxical result we have found is that a stiffer yard tends to create lee helm, when the usual goat has just a little touch of weather helm.  It is quite counter intuitive.  Stiffer spars mean a deeper sail and potentially less sail twist, both of which should increase weather helm.

This has also been observed in the balance lugs of Lymington scows where stiffer spars and boom vangs (kickers) generally force the sail to be moved back to maintain balance.

It may be a sail depth effect, with more camber being developed in the front part of the sail.

Experiments continue.

Mast Weights – Goat Island Skiff 

Boat

Mast type

Material

Weight

Notes

Hyndman OZ

round solid

Fir

?

MAM

Flagpole taper

Aluminium

18lbs

a

R Harvey

square hollow

Fir

24.7lbs

Ian Howick NZ

Hollow 76mm tapered

Carbon

6.6lbs

b

Common/averag.

18-20lb

Bruce Taylor

Square hollow

Hoop Pine (Paulownia infills)

7.4kg (16.3lb)

BobWes

Square hollow

Radiata Pine with DF inserts

9.8kg

(21.6lb)

George Isted

Square Hollow

Doug Fir with WRC inserts

9.5kg

(20.9lb)

Paul Hayslett

Square Hollow

Old growth Fir

WRC inserts

10.3kg

(22.7lb)

Notes

a – Flagpole from where?

b – Carbon Mast: C-Tech New Zealand – 76m ID mandrel, tapering to 45mm ID at the top. Wall thickness also tapering: Bottom meter 2.4mm wall, then 2.0mm wall for the next meter or so, then 1.5mm wall to the tip. Extra sleeves on the inside at the base and partner height. Calculated stiffness at least 30% above the hollow wooden box mast

Measurements of Yard Data (what was the defl weight?)

Boat Owner

Yard Diam.

Material

Weight

Spar

Deflect

Sail Maker/Yr

Notes

Christophe NH

35mm

Douglas Fir

57mm

Duckworks 2010

a

Christophe NH

Duckworks 2010

b

Woodeneye OZ

40mm

Radiata Pine

2.2kg

47mm

Storm Bay Sails 2010 (Tas)

a

Woodeneye OZ

40mm

Radiata Pine

2.2kg

50mm

ditto

b

Woodeneye OZ

38mm

Aluminium 3mm wall

3.2kg

20mm

ditto

Ian Howick NZ

Taper

38mm -24mm

Carbon

1.15kg

20mm

c

Clint – Portland

50mm

Eastern Spruce

51mm

BobWes

Michigan

40mm Hollow Box

Eastern Pine

2.2kg

35mm

12kg @ mid-point

SailRite (home sewn)

d

e

George Isted

Taper

40mm

-30

Fir

2.56

50mm

Sanders

Lymington

f

Paul Hayslett

Taper

38mm

Old growth Fir

2.6

42mm

Duckworks standard

Notes

a – original radiata yard

b – radiata plus carbon tow – 2 x 1” wide tow top and bottom of yard.

c – Carbon Yard: C-Tech New Zealand -38mm ID, tapering to 20mm ID at the tip. 1.8mm wall with some reinforcement at either end and the middle where the halyard attaches.

d – four 15mm x 35mm staves lapped joined; 20mm hollow; end plugs and spacers used to support structure.  50mm x 50mm blank planed to 40mm x 40mm; 10mm walls.

e – Remeasured deflection using 15.9kg (35.05#) at 40% from forward end of yard and at the ¼, ½ and ¾ marks.  Deflection at 40% = 33mm.

f – Some block and leathering included in weight

Measurements of Boom Data (what was weight used?)

Boat Owner

Boom X-sect

Structure

Weight Spar

Wt

hung

Defl

mm

Notes

Christophe NH

Solid Square

52x35mm – Douglas Fir

10kg

17

BobWes

Square Hollow mk1

45mm x 65mm

Ply sides 6mm

Top and bottom 16mm WRC

2.18kg

12kg

16

a

BobWes

Rect. Hollow

mk 2

45 x 60

12mm timber walls

2.1kg

12kg

7 Vert

12

Hztl

BobWes

Rect Hollow

mk2a

43 x 58

11mm walls

2.26kg-

incl. finish and blocks

12kg

28mm

vert-

Above

put through thicknesser

Bruce Taylor

(NSW

Square hollow

1. 60mm x 49mm Radiata Pine

10mm Radiata pine staves

Paulownia infills (Broke)

2. 65mm x 55mm Meranti (lightweight) 12mm staves Paulownia infills

2.2kg

3.3kg

10kg

10kg

15mm

8mm

Not stiff enough

Stiff enough

Clint – Portland

Solid round

55mm x 45mm Eastern Spuce

Watermaat – NL

Square solid

72mm x 36mm European Fir

stiff

George Isted

Square solid Mod

70 x 50 Fir routed to I-Beam shape

6.8kg

incl rigging

10kg

8mm

stiff

Christophe

NH

Solid Rect

FrankenBoom:

Main Body: 73×35

Ends: 56×35

5.7kg incl rigging

14kg

5mm

b

Dave
New Jersey

Square
solid

Laminated Douglas Fir

40mm tapered to 32mm

3.3kg

10kg

20mm

c

Dan

Perth, OZ

hollow

Cedar 12mm 64 x 40mm

glass tape and infills at load spots

2.66kg

12kg

10mm(vert)

22mm (horizl)

Paul Hayslett

Conn USA

Standard round

solid

Old growth Fir

2.6

10kg

38mm

BobWes

Round, Hollow Birdsmouth

CVG Douglas Fir

4.45kg

10kg

7mm

d

Notes

a – Revised data (original data: 20mm deflection with 10kg) after remeasuring 6/6/2011

b – 2 vertical staves sandwiched between 2 horizontal staves with the lower horizontal stave coming up short of the ends by 40.5cm (16″) on each end

c- Intended for lashed foot sail which was cut with ~50mm of round

d – Spar is 12’8” long; 56mm diameter; 12mm walls

Effect of Carbon Tow on spar stiffness

Nil – a modest amount makes no difference.  See link below.

Carbon tow added to GIS yard by Bruce Taylor (Woodeneye)

Lug Rig and Sail Settings – Goat Island Skiff

Great discussion on shared rigging modifications for the Goat (July 2012) – Traveller position, change in boom/mast lashing, downhaul changes, sheeting angles

Pauli

BTW, much, much earlier in this thread, we discussed a number of small tuning experiments, but we haven’t posted any results except for spar deflections. Here are a few bits of feedback.

I moved my traveler back to the halfway point between bulkhead #4 and the transom. This completely eliminated the problem of the tiller getting hung up on it when tacking. All the way back at the transom, the leech doesn’t tighten properly when sheeting in. That’s okay at the midpoint. I keep it rigid tight. I moved the first block on the boom to the clew and usually take the sheet directly off the second block, rather than feeding it down to the block at bulkhead #3 and up again. I find this setup comfortable, snag-free, and responsive.

(I know I may be putting undue strain on the inwale at the traveler. There is no framing there to support it, as there is at bulkhead #4. But I haven’t seen any damage yet.)

I was getting a lot of weather helm, and countering it with the rudder was slowing me down. Shifting the halyard and downhaul so that there was a bit more sail in front of the mast fixed that. I’ve got a full 16″ there, with the luff just about parallel with the mast. The helm is so well balanced that I hold the tiller directly on the centerline of the boat on most points of sail. There is a noticeable increase in speed.

Following Joost’s lead, I got rid of the square lashing holding the boom to the mast. I re-tied it from the front of the boom to a loose loop around the mast. It’s purpose is just to prevent the boom from sliding forward when I raise the sail. The downhaul holds the boom close enough to the mast so the lashing is unnecessary. No more tangles with the cleat when raising and lowering the sail and no more jamming of boom against mast.

Adding a stylish black banner at the tip of the yard does nothing for the boat’s performance, but it sure looks good!

Read more: http://www.woodworkforums.com/f169/gis-sail-tweaking-142194/index12.html#ixzz21sjzkXpY

Warmbeer

Holy beep, Paulie, everything you have just described, is the way I changed my rigging as well.

(1) no more square lashing, I use the loop around the mast to the forward boom end like you.

(2) I’ve tried different amounts of sail forward of the mast and settled on the 16 inch spot as providing the most balanced helm. I too moved both yard lashing and boom retainer to balance this out.

(3) My traveller is where yours is, about 16″ off the outside edge of the transom and I like it there, but I still bring it down to ratchet block at the midseat rope saddle. I switched to a big though light Ronstan series 55 ratchet block for the sheet. It grips well and makes very cool ratchety sounds.

(4) I ran my outhaul under the boom to a boom lashed block about 1.5 feet aft of the mast using some leftover spyderline, then down to a 3 to 1 terminated with a Ronstan RF45131 series 40 block with cleat on the deck just aft of the mast. With this arrangment I can tweak the downhaul pressure (no choice actually!) almost like a boom vang/kicker. Another aspect is that it pulls the aft end of the boom towards the bow. This opposes the forward boom lashing, and the effect is that the boom stays very snuggly against the mast without a square lashing.

My hope as well was that this would act as a stay to the boom to help prevent bending, but in reality it only increases the bend. O. The only solution to the bend issue is I think a new stiffer boom, and I am reading the ongoing discussion here and on facebook with great interest! I did stop by Home Depot about five times to wander the wood, and see what might be of use, and came upon a stock of already machined high grade Douglas Fir “rail cap” in lengths of over 12 feet. It is heavier, and very stiff, and I am tempted to bring one home and give it the stiffness test, measuring my stock 40mm sitka spruce in comparison. Not as sexy as a hollow box, but it would be fun to weigh it and bend it for data, and you never know, it could work well.

I really like having a light boom. It’s responsive, and you can point it up at the sky sailing by the lee in light airs without breaking out an oar for a makeshift whisker pole. It would be cool to have a boom twice as stiff, but not any heavier!

Pointing – I’m still not quite happy with my pointing ability, but it’s better! I can only judge against the marconi rigged sloops and a few racing dinghys where I sail. It is very much fun out in the ocean pacing 30 and 40 footers in different points of sail, and you’re the only one out there in a small boat! A constant that I have noticed is pretty standard – for a change in apparent wind direction, the Goat prefers a course correction rather than a sail adjustment.

Wind Indicator – I added a mast head wind indicator (modified Davis “spar fly”), and I use it constantly in conjunction with two sets of tell tales.

Sail – My Duckworks sail is stretching out I think – which is a good thing. I am using it unlashed without battens, and I give it a fairly loose outhaul sometimes if I want more depth in chop. It does help, (thanks Mik!) I am still really curious about the shape and attack angle of the leading two feet of the sail when it is on the leeward side of the mast (no mast wrap), as I think this has everything to do with how well the boat points on that tack. The only adjustment I have to try to tweak that is the choice to lash or not lash the foot, and the amount of outhaul pressure. I can’t wrap in my head how adding downhaul pressure will change much of the sail shape other than the tension in the luff. I can make the boat perform well pointing with the sail on the lee, but I have to give up some degrees of pointing compared to the mast wrapped tack!

Woodeneye: 

Hi Paulie and warmbeer

The loop around the mast to the front of the boom is, I think, and good idea. I have not tried removing the square lashing so will have to give that a go.

Now that you have this restraint on the boom, have either of you tried moving the downhaul any further aft to increase the vanging effect?

I am a little worried about sheeting from a traveler between BH4 and the transom due to the lack of support there. Perhaps a big screw or 1/4″ bolt epoxied through the inwale and gunwale strengthen it, but the boat is very strong and probably doesn’t need it. (I have tipped mine over on the beach while fully loaded with water to empty it and there hasn’t been so much as a groan from the hull). As I carry my traveler drum tight, I will leave mine at the transom. On a beat, I’m hauling my boom further aft to create weather helm (otherwise I have lee helm), so the sheeting from the transom works well for me. Certainly I have no issues with generating enough leech tension. By the way, I carry two 55mm ratchet blocks, one on the traveler and the other on the mid seat. Both can be turned on and off. As I’ve changed my mainsheet to 6mm polilite, this makes it more comfortable to manage when the wind gets up. This lightweight sheet is great in the light stuff as it runs so freely and helps keep the boom out and the sheet out of the water.

Paulie, I think your stayed boom will be great for hooking up around body parts and PFDs.  Worth a go though for fun. Rest assured, you can make a very light and stiff boom. Don’t be tempted to use heavier timber to achieve the stiffness. Use the lightest timber you can as it’s all in the dimensions. I managed to find some super light meranti for mine, so that it’s stiff but still light. Still taper it at the front and back to make it look nice. Has anyone made an I-Beam boom?

As for pointing ability, the most important thing here is leech tension and boom position. You will need to have the back of your boom pointing at the transom corner, and to do this you need a tight traveler to keep the boom there when you crank on that last bit of mainsheet that puts in the leech tension. The aim is to have the leech straight like a blade. Naturally, the board has to be all the way down and of course, you need a drum tight luff as well, so plenty of downhaul is needed. I’ve found that having the automatic Ronstan series 55 ratchet on at the traveler helps because you can tension the leech with the mainsheet to where you want it and then just let some of the tension go. This takes some pressure off the middle of the boom while the S55 holds the leech tight. Vital also to pointing is fore/aft weight distribution which needs to be centred as close to the centreboard as possible while keeping the boat flat to generate the maximum lift. Do this and there’s no reason for you not to be pointing at 80 degrees, which is close to matching those Lasers and excellent for this rig. Over time I’ve become quite amazed at the potential of the lug rig.

__________________

Cheers

Bruce

WarmBeer: 

Hey Wood,

I’m not even close to having the sail sheeted in that far with the boom to the lee of the mast. I find that it stalls the sail – no forward vector from the sail, so I intentionally sheet in less than I would in a laser or FJ in order to maintain power. I think you may have the answer to my dilemna! (at least I’m very much hoping you do). I was thinking that for pointing it is the leading edge of the sail that make all the difference, and the curve in the first few feet. You are saying that a flat trailing edge is just as important?

Are you restricting traveller travel? If so, are you doing this assymetrically?

BTW: I like the idea of adding another ronstan 55 at the traveller, I understand why you are doing it, and I happen to have a series 30 autoratchet gathering dust, that now has found a home. )

Boatmik: Brilliant posts Warmbeer, Pauli and Woodeneye!

In general the closest you want to sheet the front sail on any boat is about 10 degrees off the centreline from the downhaul position. This means a slight asymmetry which might work well because the sail is slightly freer with the mast on the leeward side.

More foot depth will usually help more with pointing … but maximum depth should not be too much more than 10% in the bottom of the sail – or too much drag.

This is only relevant to the front sail on any boat. The next sail back needs to be flatter, particularly at the heights it overlaps with the other sails and also sheeted in closer.

But most goats only have the one sail.

With the two sails trimming the second sail means trimming in to give the weather helm you want. This should be a small but obvious amount. Generally if the tiller is having to be pulled up 4 degrees or more then there is too much weather helm.

It can be worth measuring these 10 degree and four degree angles to imprint in your mind what they look like or even put reference marks on the hull somewhere.

The next part of the second sail (mizzen on the yawl goats) is generally you want it to luff just a tiny amount … so if it is full sheeted on then the main might need to be moved back slightly relative to its mast. But the most important thing is to get helm balance.

Downwind and crosswind with the Yawl I would keep the boat very flat to ensure no weather helm from heeling the hull and dump as much much of the mizzen as necessary for neutral helm. In general you want to bear away with the gusts … if it is small maybe 5 degrees but in a big one could be 15 to keep the boat balanced.

With the cat rig downwind if you have weather helm check the boat is flat flat flat or even heeling to windward a little.

MIK

Sail Cloth Type for Goats and OzRacer/PDRacer

[George Isted]

Just a quick question on sail material, most appear to have sails made from polyester/Dacron, while this look traditional and suit the boat do you think there would be any improvement to be had by moving to a higher-spec non-stretch cloth (Pentex for example).  I suspect it wouldn’t make much difference on a simple rig like this but was interested in your thoughts.

[Boatmik] As far as higher tech sailcloths – I think the rigidity of the rig starts to be really important.  You need everything set up at really high tensions and most bits to be fairly immovable.  Quite the opposite of a lug rig – though you can see one of the areas of development is putting more stiffness into the rig with stiffer yards and particularly boom and the fitting of vangs etc.  However even with these it doesn’t really get up into the same ballpark as a modern skiff or fast yacht type of stiffness.  So the sailcloth is a bit wasted.

The other aspect is that it can be quite possible that you will sail reefed a fair bit of the time.  A medium finish dacron will respond pretty well to that treatment, whereas a hard finish dacron or the exotic sailcloths might be weakened.

With the PDRacer sails, we continue to recommend polytarp.  It provides a level but extremely low cost playing field.  Brad Hickman who has done a lot of the recent development in making the OzRacer/PDRacer sail fast was worried that he wasn’t pointing well with a polytarp sail so was thinking of a dacron one – I talked him out of it.  However he continued to develop the other bits of his rig including outhaul and downhaul adjustment of his lug.  At the recent Oklahoma messabout he was the fastest PDR by far and faster than several of the bigger boats – this doesn’t show the superiority of the PDR Concept – it shows the superiority of better finished foils, spars and sails and a clever sailor.

The other side of the polytarp sails is that they are empowering!  Sailmaking is a bit of a black art and seems out of reach for normal people, but here we have a class (Ducks) where very good performance can come from a sub $50 sail.

For the Goat I still recommend a dacron sail because of the higher loads and that it is a classy intermediate to high performance boat compared to the entry (and amusement) level of the OZRacer/PDR.  I do have a sail design for the Goat available for plan purchasers that gives the same type of simple sail  that works well, but out of a big dacron panel made up out of regular sail cloth.  The sails below are made by the same method.  

More pics at Brian’s photostream

More from my forum

[Brian Pearson]

A laminate lug sail would be a lot of fun to try, if you can obtain the laminate at reasonable cost. I would use Sailcut4 to design a broadseamed sail, then glue the panels together, using 3M 5200. It would be great to be able to see where you are going and that no one is going to starboard tack you when racing.

Our local Hood loft tried making laminate lug sails for our local Scows. They were cut quite flat so lacked power compared to the Sanders sails. The other thing people mentioned that the stiffer cloth was much harder to “read” when sailing. The luff no resonding to lift the same as a soft dacron sail.

When I have used laminate dinghy sails, they do set superbly but they are horrible when dropped into the boat. Just completely fill the hull. where as a dacron sail bundles up easily.

I found that finding suppliers who would deal with you was the hardest issue. They all deal company to company and not individuals. After searching for months and getting all the bits by driving miles, I found an e-bay supplier who sells cover materials on his site but does supply all you need of the proper items.

That’s the correct sewing thread, correct sailmakers double sided tape, star grommets and the closing tools. he can also supply any sailcloth you need.

Good luck with it if you do make your own sail.

[boatmik] I agree that a mylar scrim “regatta sail” might be a great stir!!

Peter Hyndman (Biting midge here) was told about the product pictured below by a school that is building a bunch of OzRacers.

The guy teaching is a high grade sailor of A-class cats. He built his own, which is a great background in light wooden boat building because the class has no minimum weight. He is one of the converts to the PDRs, having sailed them and finding they are a sailing boat that deserves respect.

This “fabric” was located at Bunnings and we think it is polyester with glass tow.

[Peter Hyndman]

Just back from visiting the two new ducks the boys have built in Toowoomba. (Photos taken in their school manual arts studio).

Sometime during the week there will be a fleet of four yellow ducks on a lake near there!

The sails are a bit interesting, some sort of clear plastic with glass reinforcing, used for blinds or side curtains or something, available from Bunnings for $35 for a 4 x 5 metre sheet! Won’t stretch in any direction! Check it out one day when you are visiting a hardware store near you. I don’t have a name for it, but it seems to sew and stick better than polyprop too. Grommets are plastic Coleman ones, which are very efficient and these days quite cheap.                                        

Bunnings is a “big box” hardware store in Australia.

I do have a little concern about the plastic eyelets .. but I guess they will see how they work.

http://www.flickr.com/photos/boatmik…th/5239354303/

The main question is whether it is a good weight for a sailcloth too – and remember Brian’s comments about it being hard to “read” and that you need broadseaming to get shape into it – it is too stiff for edge rounding to move to where it is needed to create the depth of the sail. Normal sailcloth does this through bias stretch.

Downhaul

[Boatmik] See Downhaul in general section above – it is the most critical adjustment for lug sails, particularly balance lugs.

Very Light Winds – In light winds when it is difficult to get the boat moving the downhaul can be a little bit loose.  This windstrength is identified by the difficulty of getting the boat moving.

Light to Medium conditions – not overpowered – Once the boat is moving reliably the downhaul should be firmly tensioned – usually a lot more than you expect

Strong winds – overpowered – In strong winds you need to be completely BRUTAL with the downhaul

Foot Outhaul

Different Conditions

[Boatmik] Some depth in the bottom of the sail is useful, but there are limits.

These are the basic setups for a single sail rig or if the front sail has the luff attached to the mast.

  • 10% draft for upwind in rough water or when you are looking for more power or the boat is tending to lee helm.  Some boats won’t point well with a flattish mainsail foot.
  • 14% when reaching with flow attached to the sail – sail tufts flowing
  • 5% in very flat water and good wind strength upwind for higher pointing – depends on the boat to some extent
  • 0% when running with the flow stalled around the sail or upwind in strong wind and flat water
  • In very light winds the sail should be quite flat and well twisted.

Strong winds and rough water

[Boatmik] Theory is that choppy water needs more power and depth in the sail down low and flatter up high.  The deeper sail low gives more power and slightly increases weather helm the flatter sail up high reduces heeling moment.  Christophe in New Hampshire has been doing a lot of sailing in rough weather and big seas and has been observing the differences when he adjusts the rig

[Christophe] Experience and approx measurement of mid foot distance from boom

Reefing

There has been a lot of discussion about reefing points for the Goat Island Skiff.

The consensus is that for regular sailing the three standard reefs are OK.

However for more performance oriented sailing or distance sailing some other options have been considered and work

[Joost] Joost found during the Caledonia RAID that the first reef left the Goat a bit underpowered with two people sailing hard.  

It is too big a step.  Some have found since that having the bottom reef only 300mm (1ft) from the boom is the best position for the first reef.

[John Goodman] found that the maximum reef was a bit much.  

We drove up to Lake Bastrop to go to the Central Texas Messabout sailboat gathering. We had a good turnout, but the wind blew 25-30 knots the whole time we where there. Of course the wind was straight into the boat ramp and onto the beach area. Only a few boats went out.

My wife and I started with Reef #2. In the heavy and very shifty lake winds we quickly decided it was not much fun and headed back to shore.  We reefed down to the #3 location and went back out and had a much easier sail. We even gybed in 25plus wind with our tiny sail.

I am thinking of adjusting the location of the #3 reef points. Lowering the tack and clew patches 12″ so the boom and yard do not touch at the front tack area. We adjusted our reef ties to simulate this condition and it seemed to work well.

With that extra 12″ we could sail to windard just enough to crawl our way off the leeshore and still tack. The tacking angle was very large so windward progress was very slow and the boat needed to be footed in order to keep the speed up in the lulls, while in the high gusts around 30 knots, the boat felt strong and could be sailed closer to the wind.

This amount of sail area kept my wife happy and made sailing the boat far easier then the #2 reef position we started with.

[SimonLew]

That sounds like a brilliant idea. The sail area goes from 35 to 42sft which is a fair bit bigger but may be more useful. I assume you feel that a bit more sail area would still have been manageable in 25-30kn. Might be too much if it’s blowing 40

My sail is being made as we speak and the sailmaker made a comment that the boom and yard will touch when reefed down but then we moved on to other things and I never thought much about it. Will see if I can sneak that change in.

[Boatmik] The windward performance with a heavily reefed sail might be improved by leaving a fair bit of depth in the bottom of the sail – unless the water is smooth.  Maybe about 75 or 100mm (3-4”) of gap between the bottom of the mainsail and the boom.  This always helps the boat point higher when the water is choppy – reefed or unreefed.

Lug Rig and Sail Settings – OzRacer/PDRacer

From Brad Hickman

I really don’t have much time in the OZ, maybe 30 hours, so I definitely don’t have anything optimized. There are three things I’ve done that have helped significantly.

First I moved the sail tack closer to the mast. I started at 400mm but the boat points higher now that I’ve moved it to 300mm.

Next I installed a Laser style mast mount wind indicator, before that I tried tell tails at different locations on the sail but couldn’t get them to perform satisfactorily due to turbulence from the mast. I now compare boom angle to apparent wind angle, since the end of the boom and wind indicator are in close proximity, and the boat seems to point well with the boom angle about 10 to 15 degrees lower than the wind indicator angle. When I have good speed upwind I sheet the boom in to about 6 inches inside the transom corner.

Third I installed a compass, seeing a compass in an 8′ Puddle Duck got a few chuckles at Sail Oklahoma but they can be a valuable tool when racing. Using the compass I kept making adjustments to sail trim and sheeting angles until I could consistently tack through 90 degrees.

In good breeze I set the draft at 8 to 10% and forget it. In lighter wind I try to use your guidelines. I only use the vang when reaching or running and give it a good tug to reduce sail twist but with 6:1 purchase it doesn’t have enough power to get the yard and boom close to parallel.

I’m sure I could get more out of the boat If I had someone to do two boat testing with but it’s hard to gauge any performance gains at this point.

Yawl Rig Option – Goat Island Skiff

Available from Clinton Chase. Goat Island Skiff Yawl Rig version

The designer’s point of view is that he likes simplicity and the GIS was an attempt to simplify everything down and is most appropriate for most sailors.  However this setup uses the original mast and has been proven out by John Goodman and his son in the Texas 200 event where they were in ankle nipping distance of some much larger boats through much of the event.

You can see more info about John Goodman’s Yawl Goat Island Skiff version here.

Case Study – more complex vanging and control systems on Lymington scows

These have been highly influential in the case of the Goat Island Skiff and starting to be important in the OzRacer/PDRacer for those looking for more performance.

There is no need to consider this if you are just cruising around or prefer the simplicity of the standard rig (like the designer!).

The case of the Lymington Scows was brought to us by Brian Pearson.  The class has been racing with balance lug rigs for around 100 years, so one would have to consider that their solutions are quite highly developed.

The information that Brian put up is on my forum – I am hoping a summary will find its way onto this summary page.

Lug Rig Heaven

Lug rig heaven 2010

Racing a Goat in a Fleet with the more complex setup

Ian in NZ asked Woodeneye (OZ) whether the stiffer yard was best for racing with the more complex rigging setup.  This is his reply.

[Wooodeneye ]

The stiff yard…definitely the way to go. There is a lot more power in my sail mainly because it is setting correctly. I’m not sure if it’s just my sail or not, but it goes to crap with the bendy yard. I will now look at upgrading to a lighter spar, either carbon or glass.

The vang/downhaul works well, but it’s definitely not a set and forget arrangement. You have to realise it needs adjustment constantly, or at least when changing points of sailing as happens on a race course. If this is not what people want, then they should stick with the original downhaul design, which is simple and works well. However, my competitive streak has come back and I love to optimise and try new things, fiddle around to try to get the best out of my rig and sail etc…..well, some might understand, others wont!

On the beats, I’m pulling the rig back to get the helm balanced and to point as high as the Lasers. This involves slackening the vang, pulling on the downhaul, and then maybe some more vang once the boom is where it needs to be.

For reaching, it’s letting the downhaul go all the way out and pulling on the vang hard. This pushes the boom forward and takes off some of the excess weather helm. Then some more downhaul to fine tune the luff, which on reaches sometimes has a slight curve on it. If I can manage it, I’ll release some tension in the foot too. Dead set, she just takes off on a reach and sings if you can get the settings right.

For runs, it is the downhaul freed right off initially, then some savage vang to get the boom across the mast even more than for the reaches, then a bit more downhaul to fine tune the luff, and then maybe even release some excess vang now that the boom is across enough to set the leach.

See what I mean about fiddling?! You wouldn’t need to do this on a Bermuda rig, but when there is a lot of pressure on the balanced lug, you have to use the vang/downhaul combination to get the boom positioned, and then fine tune each control to set the leach and luff correctly. But I’m loving the control I get from the set-up.

I now have some extra heavy duty elastic straps on the rudder blade too. Last outing in around 20-24 knots by myself, I was planing the fastest I had ever been on reaches and runs, and the blade was lifting back even with big 10mm tie-down elastic straps that were really tight! I’m now trialling the flat type to see if this works better. The problem when the rudder kicks back like that is maintaining control, especially when I need to gybe. I simply can’t because with the rudder in that position I’ll be swimming for sure.

Edit: Have now added an extra strap, so now 3 in all. Last outing (with MIK) we were planing with 2 up and the rudder stayed down! Yay!

Edit: One thing I have learned from the Lasers is that the line traveler system needs to be drum tight in strong winds so as to keep the boom out at the corner of the transom. If it’s a little loose, the boom comes too far inboard and the sail is twisted too much. I was not tensioning mine enough, so the boom was coming too far inboard on the beats. In lighter winds it can be slackened off to bring the boom more inboard. This was the opposite to how I thought this system worked! I’ve always used a track on my other boats, so have not had experience with this type.

Hull Weights – Goat Island Skiff

Boat

Weight

Year

Materials

Hyndman – OZ

This is regarded as a standard build.

127 lbs

1993

Ply – Gaboon

Glass – 50mm tape on chines and stem

Fir – gunwales inwales, side frames,transom top frame, stem.

Western Red Cedar – Balance of framing

Woodeneye OZ

105 lbs

2010

Ply – Gaboon (Brand: Joubert)

Glass – Nil

Paulownia (plantation) – frames, under deck/seat framing, chinelogs, stem, inwale spacers, cb case and rudder case spacers, mast and boom spacers, foils.

Hoop Pine (plantation) – mast, inwales, gunwales, knees, transom top, tiller

Notes

Paulownia is a light white Chinese timber available in Australia and New Zealand in quantity from both imports and plantation growing.  There are one or two suppliers starting to appear in the USA.

Fir is Douglas Fir also known as “Oregon” in Australia.  It is starting to be rare and expensive in Australia and New Zealand.  Substitutes are Hoop Pine and other Pine timbers

Western Red Cedar is plentiful in North America but has become rarer and expensive in other regions.  In Australia and New Zealand Paulownia is becoming the substitute.

Timber Suppliers

North America

USA NH 

[Christophe] [WWC] Most of it was from Goosebay Lumber in Chichester, NH, but we got a few things (mast timbers if I remember correctly) from Selectwood Portsmouth, Maine Coast Lumber, York, ME.

Australia

Duckflat Wooden boats Adelaide

Epoxy Suppliers

Australia

Duckflat wooden boats – Adelaide – great experience, advice and service

Boatcraft Pacific

ATL Composites (WEST System)

USA

Duckworks is brilliant.

Plywood suppliers

Australia

Duckflat wooden boats – Adelaide – Gaboon and others, great advice and service

Boatcraft Pacific – Various locations – Gaboon (they stopped stocking it at one point?).  Can often ship cheaper than you can buy locally.

Denman Marine – Kettering, Tasmania – Gaboon (Joubert)

Rope and Fittings Suppliers

Australia

Duckflat wooden boats – Adelaide – great advice and service – will ship

Binks Yacht Fittings – Rope and fittings – will ship

North America

Duckworks

14 thoughts on “WIKI for setting up and tuning Lug and Sprit Rigs

  1. great to see planing luggers. I very much agree on most of your recommendations, especially about the downhaul, which cant be strong enough. It means the luff must be reinforced with non-stretch rope, and I think 3 -5 mm dyneema is the easiest. Also a client of mine with a Tirrik and 10 m2 bal. lug capsized and we concluded his mast was relatively bendier than his yard. Consequently in a gust his sail bellied out and he capsized. Since than he built a stiffer mast. And very good to see modern techniques like battened crosscut sails

    • Hi Frank,

      Thankyou for your comments. A number of things on this page are experiments – over time we will find out what works best and the page will be updated.

      The big thing that most don’t realise is that the same lessons apply to lug and all traditional rigs as to all modern rigs. The big advantage of many traditional rigs is the simplicity and cheapness – much less gear for adjustment. It is nice to try and keep that.

      The battens are something my clients wanted to try. My approach during design was to assume the sail would be a little less efficient and increase the sail area to compensate. I think a little more area is more beneficial and much cheaper than battens.

      But I support my customers when they are doing sensible experiments like all the ones we are cataloguing here.

      Nice to make contact.
      Best wishes
      Michael

  2. Anyone rig” BETH” sailing canoe to row places in between sailing experiences? I had a thought it would make a nice combo somehow… Centre-board case in the way? How about a seated arrangement which makes use of the aft end of the centre-board case in some way.
    Hope to hear an answer.
    e-mail me anyone who has a mind to do so.
    Thanks,
    Robert Troff

    • Hi Robert,

      BETH the sailing canoe is too narrow to make a good rowing boat without outriggers. Also the centreboard goes through the deck in front of the cockpit so there is nowhere to sit.

      I think it pushes the boat away from the original concept too much. With my Quick Canoe design one of my customers uses a swimming pool bean bag chair to sit it and paddles with a single or double paddle.

      For short distances I kneel and use a single blade paddle and Beth goes much better than most sailing dinghies under paddle power. Won’t stay with a properly shaped canoe though!

      A paddle requires much less extra gear and doesn’t intrude on the sailing space.

      Hope this helps
      Michael

  3. Hi Mik,

    Did you ever find out how that Bunnings clear/glass reinforced “sail material” from the Toowoomba boats went?

    Duncan

  4. Paul Griffiths says:

    Hi Michael,

    Just wanting to keep you in touch with Gracious Me, the finest red GIS on the planet. She now lives at Yass NSW and will be sailed on Lake Burley Griffin and the Clyde River above Bateman’s Bay NSW by our daughter Myffy and her beau.

    The Bilge Rat and I (+ victualers) have just returned from the UK (family wedding) and enjoyed the Beale Park Boat Show at Pangbourne, Berkshire UK very much. I made a first class speech at the wedding – just thought I should let you know.

    Hope all is well. When are you coming to see us? Bilge Rat off this week for 17 days trekking with camels in the Outback. Give me water any day.

    Best,

    Bumboat Boy.

  5. […] to share information and also to make sure it was written down.  One of the resources is  the Lug Rig setup and tuning WIKI.  Another are the growing number of meetings of goat sailors, here at the Small Reach Regatta last […]

  6. […] WIKI for setting up and tuning Lug and Sprit Rigs […]