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Hi, I am in the process of restoring a wharram tiki 30, and think it should perform better than it does now.

What kind of angle is normal for a tiki 30?

Below i added  photo's of my chart plotter and main sail.

My sails are about 6 years old, but might have seen more uv light than they should.  I am putting more and more tension on the outhoul on the gaff witch help to get a more flat sail.

This winter i also want to apply a new coat of anti fouling paint,   this is one of the jobs a bit lower on the to-do list, i had to fix other things first... i have some growth on the hulls.

the boat is not to heavy on the helm, it just wants to turn a bit to the wind. is that okay or should i trim it really neutral?

any idea's?

Thanks a lot!

Bart

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Firstly any growth at all will hammer your upwind performance. The Tiki 30 has a relatively, for Wharrams, large sail area to displacement ratio. For boats in general that sail well to windward the SA/D is relatively small.

These are my opinions so feel free to disagree.

A taller mast with a full batten big roach main and bigger genoa will perk up the weather performance considerably. Modern sail materials, construction, and design allow for a much more efficient sails and sail handling systems. That doesn't mean that other ways aren't good. 

There are many factors to consider when choosing a rig. There are ways to increase windward performance albeit  possibly with more cost, complexity, and a different aesthetic.

These are pleasure boats and that makes them like women. We don't all go for the same ones.

What kind of airs were you sailing in the pic? In light air? 

But generally, 6 year old dacron is pretty much at or past the infection point of reasonable performance.  Most one-design racers I know will use dacron 1 season. Your sail looks pretty baggy and tired to me but again with out the wind conditions and a wider pic it's hard to tell. Remember the sails are the engine, without good sails you will never have good performance. I'm always amazed to see folks spend thousands on fancy electronics with 10 year old sails :(  Also without a boom and outhaul I don't know how a Wharram wing sail can ever be as flat as needed for good pointing and heavy airs. The outhaul flattens the bottom third of the sail. 

In light airs the bottom must be clean and smooth. A tiki will never point as high as a J boat but saddling it with a dirty bottom is just asking for frustration. 

So my first steps would be clean bottom and new sails. 

Hi Boatmith and edward, thanks vor your reply!

I think i underestimated the effect of some growth on the hulls, but that will be fixed next winter when i have to paint the bottom en sides of the boat.  for now i will scrub her when on a beach i think. 

I know this rig isn't the greatist performer when it comes to power and upwind performance. A friend of mine is building al f31 farrier, and that will be faster but  only the mast and sails are so much more expensive and complex.. beautiful, but i like the simplicity of the wharrams. I still like to get the best of it..

I was not sure about the sails, i find it difficult to see where the deepest point of the profile is, thanks to the sleeve  i think.

but just the age is probably a reaonable indicator.

Nevertheless, what kind of tacking angles are to be espected? my former boat was a monohull so i am quite a beginner in multihull country. 

Possebly i should look at the vmg windward as a indicator for performance, not just the angle.

As new sails not cheap,  this might be the moment to ad a meter or so to the mast and get new sails then?

I am not a blue water sailor just coastral waters in the netherlands so staying upright in high winds is not that much of a problem, i will be in a harbour by then.

I ll go asking jeckells about the sails/ options.

Thanks again,

Regards, Bart

Expect to easily get 50 degrees off the apparent wind, anything higher than that depends on conditions. Pointing up on a wharram can be an exercise in finesse. A big sea will kill your speed and your pointing ability.

Some pointers on getting the most out of the windsail.

1. Boat speed. Don't try to point high until you have some good speed. As the speed drops then bear off a little until it builds again then head up again. If you try to point too high you'll have full sails and no speed and therefore you'll get lots of leeway.

2. Don't oversheet the mainsail. As there is no boom then the mainsheet acts kinda like the outhaul on a boom. This flattens the sail in a blow and adds shape when the wind is light.  

3. If you don't have a traveler then make / install one immediately. when i had my tiki 30 i didn't have a traveller for the first few years and when i finally got around to fitting one it made a world of difference. Use the mainsheet to get the best sail shape then use the traveller to set the position of the clew. In strong wind you need a flat sail ( lots of mainsheet tension) and in lighter winds you need a sail with more shape, i.e. fuller. Play around with the traveller position and you'll find that sometimes you'll have a nice full sail with the traveller well to windward to help get the sail positioned along the centreline.

4. Play around with the gaff position. Lots of peak halyard tension for upwind in breezy conditions  and less for a fuller sail in light winds.

5. If you have too much weather helm, drop the traveller to leeward a few inches at a time till its acceptable.

6. Try a barber hauler on your jib sheets to get the lead more to the centreline of the boat. 

7. Make sure the rig is tight. A floppy / sagging forestay will kill pointing ability. To get the rig tight, slacken the shrouds and tighten the forestay. Then tighten the shrouds. I found that you can get the shrouds really tight if you attach all 4 shrouds then run a line between the port and starboard forward shrouds and pull them inwards towards each other. this will take up the slack and tension the rig. Now the aft shrouds will be floppy. Take up the slack until they are tight then release the rope between theforward shrouds. Then Put the frapping line between the stern shrouds and repeat, by taking the slack out of the forward shrouds. Keep going till the shrouds are tight.

Hope this helps.

Marty



Bart Koop said:

I was not sure about the sails, i find it difficult to see where the deepest point of the profile is, thanks to the sleeve  i think.

but just the age is probably a reaonable indicator.

A couple three draft stripes and sail telltails will help greatly in understanding the shape and air flows. Also a couple leech tailtells should be added to at least the top batten on the main/jib.

Possebly i should look at the vmg windward as a indicator for performance, not just the angle.

Be careful of VMG, it's great at the first point of a new course but then some GPS units try to get you back to the original course line. Be sure you understand "how" your particular GPS is calulating VMG. 

As new sails not cheap,  this might be the moment to ad a meter or so to the mast and get new sails then? 

A good set of tell-tails are invaluable to trimming. For instance on the jib of the boat I race, we have four tell-tails up the the luff about 8 inchs aft and the lower two have three more tells extending aft. This allow note when the wind beginning to break before the luff actually back winds. Also the leech tells show smooth flow off the leech. 

If you can crew for a winning race boat with helmsman/skipper who will explain the trimming you will learn much very quickly. 

Edward

I use a 2:1 purchase on the peak halyard, a 2:1 on the throat halyard, a 3:1 on the cunningham, a 2:1 on the downhaul (standard Wharram on the front of the mast) and a 5:1 on the mainsheet (changing soon to a 6:1). I find that in strong winds (common on SF Bay where I sail) that pulling on all four corners of the mainsail is necessary to get the shape you need. When you make the sail flat with all of these purchases, the boat can really go to weather in strong winds. I am most surprised by the 2:1 on the throat halyard which has really made a difference to the shape at the front of the sail - just shows that to get shape along the luff of the sail, you need to pull it at both ends - not just the bottom. My mainsail is no longer new, but with the combined throat and cunningham purchases I can get the draft forward in strong winds, instead of the belly in the after-half of the sail which is common on the Wharram rig when the wind is up..

With the 2:1 on the peak and throat, do you find the extra halyard lengths a pain to handle around the base of the mast / on the deck? 

I do it like this, which I think might leave less line on deck. Anyway, I've got used to it already with the 2:1 on the peak halyard.

With this set up, you still end up with two mast lengths on the deck when hoisted ? (I think it's unavoidable when there's a mechanical advantage)

Yes, there is quite a lot of line on the deck, but its not as bad as you would think. Well worth it for the ability to trim the sail. Its also easier to pull the sail up!

It sounds as if your not turning the peak halyard back to a winch, in that case you could also mount a block& tackle to the beam/deck/mast and use a rolling hitch to put that last force into the halyard. Not as fast as fixed system but should result in less overall clutter.  Many ways to skin the cat :) 

Roger said:

Yes, there is quite a lot of line on the deck, but its not as bad as you would think. Well worth it for the ability to trim the sail. Its also easier to pull the sail up!

Goedemorgen Bart vanuit Thailand 

we have two Tiki 30's rigged as per plans ,so with the  Tiki wingsail . 

Over time we have found that  for best performance, windward as well as other wise : 

- mainsail should be cut FLAT , no belly at all, flat as a pancake

- "tuneability" of the sail is important ,so you do want a mainsheet  traveller  and you do want 2: 1 halyards to make tensioning them easier, also when under load .The extra line clutter compared with a single purchase is but a small price to pay for much better tuneability . Sticking a good number of tell tales on main and jib makes tuning a lot easier. 

- Adjusting and tensioning the halyards ( as well as dropping the sail in adverse conditions) is soooo much easier if you run the down ward part of the halyards outside the sleeve of the mainsail rather then trough it. Just make sturdy cleats screwed  into the top of the mast beam about a meter from the mast , no block at deck level needed . Price you pay compared with a  halyard run through the sleeve is a slightly increased wear on your peak halyard as the gaff will rub against it . We still get 4 years or more  out of a ( peak ) halyard so it is not really a problem .

- Forestay tension Is important if you have a roller reefed jib. If you have a hanked on jib then it matters   less as the tension that counts is the one of the luff of the jib. We have a new "Hitia 26 " ( T 26 hulls  but no cabins , wider beams , larger rig ,big flat deck ,Cookie style . On this boat we do not have a roller furler but a hanked on jib with two reefs.  Forestay is not attached to a bridle but to a beam with a gull striker. Jib halyard is single purchase, luff tension is achieved by a 2: 1 down haul , led back to  the foredeck where there is a small winch . This way you can achieve really serious luff tension. We are still test sailing the boat but it is already clear that  the boat has very good windward performance.

Hope this helps 

                    Maxim Jurgens 

                         Siam Sailing, Phuket

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