Wharram Builders and Friends

A Photo & Discussion Forum for Wharram Design Enthusiasts

tiki 26 performance with dagger board VS without dagger board

We are in the early stages of building a Tiki 26. 

I am wondering if anyone has experience with a Tiki 26 with a dagger board and has noticed any difference in performance as opposed to one without a dagger board.

 Ie, reduced slippage or higher pointing with the dagger board.

Or do they usually only install them on the Bermuda rigged boats?

Thank you

I

Views: 1868

Reply to This

Replies to This Discussion

In my plans there are no dagger boards, but I have seen it in the study plans. The ones in the study plans are in a very forward position, so I don't think that they could be useful. I have not seen any T26 with dagger boards.

Wharram cats are not "high performance" by nature.  I don't see daggerboards improving on their ability to go to wind.  Loading will have a greater affect.  Don't pile endless stuff onboard.  Sail light with good friends, music and laughter in your heart and you'll be amazed at how soon you reach your destination.

I wouldn't add dagger boards to a Tiki 26.  The hulls have such a sharp V-section that they have a really good grip on the water anyway.  The fact they can't point quite as high as many monohulls isn't down to the lack of boards or deep keels, I suspect it's largely becuase the masts are fairly short and the sails of low aspect ratio.

The pointing angle is made up for by the fact you can go faster, if you know how to sail a Tiki.  I had a long beat down the English Channel into a strong southwesterly in my T26, and we were keeping up with 30 foot monohulls in terms of progress to windward.  We had to do a few more tacks because we didn't point quite as high, but by keeping the wind a little bit more free we got enough power to sail faster.  In a Tiki you shouldn't try to squeeze every last degree of pointing angle out of it, much better to sail faster, have more fun, and still get there quicker...

Alan Barber installed a centerboard on a 35' Wharram... Tangaroa?  and did a Utube of sailing it.  35' wharram catamaran with centerboard In the comments section he wrote this: 

"Both these things can be alarming to a cat sailor especially on the first occasion you experience it after fitting the c/b. We have covered a lot more miles since then and are very happy about the c/b. Basically we can easily sail to windward now, comparable most cruising mono's. Before center board the windward performance was virtually non existent, which is a safety hazard. If the boat weighs 6.5 tonnes with all our gear and needs all the help it can get. Happy sailing. Alan"

    It is a bit absurd to suggest that there would be no benefit to a centerboard on a Wharram.  As passionate as folks are about their Wharrams, there is room for improvement in a number of areas.  Other designers have moved forward to address things like leeway devices... centerboards, daggerboards, and low aspect ratio keels, as well as recognizing that transom sterns offer resistance to hobbyhorsing as well as offering more interior room.  They have recognized the benefit of rigid beams also.  The main and probably only benefit of lashed construction is easy disassembly, but that is not insignificant, however there are other ways to accomplish this that work equally well.  The deep V hull is great for ease of construction, and any divergence from that adds time and complexity, but also benefits, and hull construction is only a small part of the entire project. 

    It's OK to love Wharrams for their simplicity, ruggedness and beauty. You can't mistake one for anything else, and we all know that probably more Wharrams have been home built and crossed oceans than any other catamaran, but at the same time it's silly to pretend that there isn't room for improvements, or that other designers are somehow misguided.  I look for example at the work of designers like Bernd Kohler, who's flat bottom designs are nearly as simple to construct, and Richard Woods, who has taken things much further, at the price of more complexity, mostly in pursuit of performance.  Personally my priorities are ruggedness and safety first, followed by payload and comfort (which often equals safety due to lack of fatigue), and of course low maintenance cost, with performance in terms of speed pretty much at the bottom of the list, though performance in terms of being able to sail to windward is important to me in terms of safety if nothing else.  Wharrams and Wharram derivatives have been built with centerboards, daggerboards, and leeboards, which tells me that this is important to many people.

                                                          Dean

Boards certainly improve upwind performance due to less slippage, which entails (1) less ground lost (leeway) and (2) higher lateral resistance to wind, and therefore more power and speed.  

Item (1) translates to a higher effective course on water: less leeway for the same rig vs. wind angle. I see no reason to see an improvement wrt the latter, because having a board changes nothing in the rig itself: its geometry makes it efficient at certain angles, and that doesn't change (very marginally though, the increased lateral resistance may help at the extreme angles, which do not provide the best gains anyway => IMO, forget the part about pointing higher, but expect improvements upwind. 

Another interesting centerboard / dagger board installation on a catamaran inspired by Wharram is David Omick's Minimus II.  Added as an afterthought to this interesting quadraplane?  small open deck catamaran, it has had a fantastic effect in tacking.  David didn't install it for leeway, but to help the boat come about in a tack.   A very interesting installation, it is either fully deployed or not at all... through a slot in a deck board, and uses an inverted pyramid of dyneema lines keeping it in place, and a lashed board to hold it down:   Minimus II description and construction

Sailing Tsunamichaser for the last 13 years along with a Tiki 21, a Hitia 17, and a Pahi 26 plus crossing from San Francisco to Hilo Hawaii on Beat Rettenmund’s Aluna has taught me one thing. Paying attention to sail trim, where lines run to and how weight is trimmed make a huge impact on the ability of a Wharram to go to wind. Will dagger boards, keel fins or other such anti slip underwater features increase performance? Probably. Will a Wharram ever be a high performance sailboat? likely not. Are they fun to sail? Yup. It’s a big commitment to build one. Make it your own for how you want to live and of course experiment. These are not boats out of a box. They are love affairs.

One of the greatest advantages of the Tiki design is the simplicity of form and function. For such a simple low tech form of hull, beams and rig - you get a very capable boat. By adding boards you will improve the rate of leeway only, and only when going to windward. Otherwise the long time spent on other points of sail you are lugging around extra weight and an underwater slot causing slight turbulence and drag. There is also the risk of collision with an object or shallow ground with a daggerboard and the resulting damage that may cause to board and case. My advise is to keep it simple and enjoy the freedom that will give you!!

On my Tiki 21 I added 80mm hardwood beaching keels (see pic) to take the wear and tear of beaching the boat. I do feel this added a bit more bite in the water and reduced her leeway a bit. How much? Who knows? The Tiki30 and 38 have similar small aspect type keels.

I have sailed many Tikis and as other have already commented, it is a far better investment to have a good set of sails and have good sheeting systems etc in place to optimise the efficient wingsail rig. On my Tiki21 or my Tiki30 I will always sail past like sized cruising monohulls to windward.

If you are into high performance sailing and racing then it would probably be better to go for a different design that suits those needs entirely.

Happy sailing

Rory 

Spot on Rory. Your experience on the Tiki's mirrors mine on my 26 in the English Channel, and also on a Pahi 52 beating up the Red Sea.  Both had well cut new sails, and attention was paid to correct trim.

Rory said:

One of the greatest advantages of the Tiki design is the simplicity of form and function. For such a simple low tech form of hull, beams and rig - you get a very capable boat. By adding boards you will improve the rate of leeway only, and only when going to windward. Otherwise the long time spent on other points of sail you are lugging around extra weight and an underwater slot causing slight turbulence and drag. There is also the risk of collision with an object or shallow ground with a daggerboard and the resulting damage that may cause to board and case. My advise is to keep it simple and enjoy the freedom that will give you!!

On my Tiki 21 I added 80mm hardwood beaching keels (see pic) to take the wear and tear of beaching the boat. I do feel this added a bit more bite in the water and reduced her leeway a bit. How much? Who knows? The Tiki30 and 38 have similar small aspect type keels.

I have sailed many Tikis and as other have already commented, it is a far better investment to have a good set of sails and have good sheeting systems etc in place to optimise the efficient wingsail rig. On my Tiki21 or my Tiki30 I will always sail past like sized cruising monohulls to windward.

If you are into high performance sailing and racing then it would probably be better to go for a different design that suits those needs entirely.

Happy sailing

Rory 

Beautifully said.



Thomas Nielsen said:

Sailing Tsunamichaser for the last 13 years along with a Tiki 21, a Hitia 17, and a Pahi 26 plus crossing from San Francisco to Hilo Hawaii on Beat Rettenmund’s Aluna has taught me one thing. Paying attention to sail trim, where lines run to and how weight is trimmed make a huge impact on the ability of a Wharram to go to wind. Will dagger boards, keel fins or other such anti slip underwater features increase performance? Probably. Will a Wharram ever be a high performance sailboat? likely not. Are they fun to sail? Yup. It’s a big commitment to build one. Make it your own for how you want to live and of course experiment. These are not boats out of a box. They are love affairs.

Reply to Discussion

RSS

© 2024   Created by Budget Boater.   Powered by

Badges  |  Report an Issue  |  Terms of Service