a better tiki 21

Discussion in 'Multihulls' started by guzzis3, May 7, 2019.

  1. redreuben
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    redreuben redreuben

    The thing about the Tiki’s is simplicity. The deep V hull is about not needing boards, and the low freeboard low windage profile is apart of that.
    Raise the cabin, fatten the hulls and then you need boards and then it’s not what it was designed for.
    It’s a big Hobie with room for lunch and beers.
     
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  2. waterbear
    Joined: Mar 2016
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    waterbear Junior Member

    The Acorn vs Janus profile comes from the free Acorn study plan on Woods' site. I added the Tiki 21 for comparison.

    The Tiki profile is from the bulkhead located at the center of the cabin. If you want to verify the scaling the inner radius of the Tiki bulkhead is 12 1/2 inches, while the Janus bulkhead is 48 inches tall (probably to fit on a sheet of plywood).

    Having seen the Tiki 21 plans I get the impression Wharram designed the boat in the same manner.
     
  3. waterbear
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    waterbear Junior Member

    Not everything about a Wharram is simpler. The beams for example are curved and tapered I-beams. One must loft and cut the center web, then drill a bunch of holes, then stitch and glue the thing, then fillet the all the inner corners. Anyone who's built a boat knows it doesn't stop there, because you have to sand and paint all those crevices.

    [​IMG]

    By comparison, Richard Woods' beams are boxes. Just rip the wood on the table saw and glue it up. No crevices to hand sand or paint when your done. They look stronger and stiffer to boot.

    [​IMG]
    Wharram claims 400 hours for the Tiki 21, Woods claims 350 for the Janus. There may be less work in the Tiki, but it's not a whole lot less, and when you're done you have much less boat.
     
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  4. guzzis3
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    guzzis3 Senior Member

    And that was my point. I have not seen the tiki 21 plans, as I said, but the tiki 30 and tanenui are both horrendous. I reckon you'd pretty much have to be trying to make a boat so conceptually simple so terribly wasteful of materials and time. And then to charge twice the going rate for the plan set... Surely there is an opportunity there for some enterprising soul.

    Anyway, had a bad day so this is a problem for another time. Some vile swine came into my front yard yesterday and stole an air conditioner. I've had scrap metal stolen before and the house proper got knocked off about 4 years ago. Next door have to right idea, big fence and 2 dogs. Sorry...cranky...venting...
     
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  5. redreuben
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    redreuben redreuben

    I’m not tying to defend the Tiki or Wharram, just stating what I see. The curved beams would be part of the low freeboard picture. If it was before epoxy maybe it’s because I beams don’t hide the rot
    If you want modern knowledge in a traditional style and that happens a bit with monos and power craft and cool cars your pretty much looking at a custom design.
    A Wharram replica if you like, same look, better engineering, like MG replicas.
    If you see all the issues just build it your way, anyone who redesigns it is just going to get shot down or sued for copying.
     
  6. guzzis3
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    guzzis3 Senior Member

    I wasn't thinking of something so close it'd be considered a copy, just a really simple cat in a Polynesian style. You are correct of course Wharram has always been paranoid about windage because his boats only have the hulls for purchase, but as I said above I've seen all too well what an oversize set of rudders will do. I am also not convinced Wharrams concerns are well justified. Decades ago cat designers made them low because of the fear of windage, but as time has gone on they have gone higher and higher and the problems seem to have not manifested to the extent expected. And anyway it's an opportunity to put leeboards on a boat and you know I couldn't resist that :D
     
  7. redreuben
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    redreuben redreuben

  8. Manfred.pech
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    Manfred.pech Senior Member



    Another design of Bernd Kohler without a bridgedeck cabin like the Tiki -- but not tikilike. Some of them are sailing already: . KD650page http://ikarus342000.com/KD650page.htm


    [​IMG]
    LOA hulls 6.50 m without rudders
    Beam c/c 3.00 m
    Beam catamaran 3.50 m
    Beam on trailer 2.00m
    Draft hull/rudders 0.33/0.54 m
    Weight empty 340 kg
    Weight CWL 760 kg
    Sail area 18.6 m2
    L/B hulls 1 : 16.6
    Prismatic coefficient 0.568
    L/B ratio center line 50 %
    Construction time about500 hours
    Gunter rig plan
    After many requests Gunter rig plan


    [​IMG]
     
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  9. Angélique
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    Angélique aka Angel (only by name)

    I admire most of Dudley Dix's work, but not when he did a 38' Tiki style boat, I don't see improvement to the original, and he doesn't sell the plans anymore.
     
  10. guzzis3
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    guzzis3 Senior Member

    IMO a worthwhile design. You can keep the self tacking ijb though. I note the owner who built with an overhanging bow. Angle the transom and curve the shear...

    We shall not discuss the bridgdeck mounted centerboard because no one wants to have THAT discussion again! :D I'd fit leeboards though...

    I remember the backpack. There were a few designers better known for monos who turned to multis to try and sell some plans. Most overlooked the details of building and using a multihull. Some designs, like Bruce Roberts efforts, were truly appalling.

    BK has always been "unique". I'm not sure I'd be ready to embrace boats that unusual. I remember some discussion here about how effective his asymmetrical hulls were.
     
  11. Banzai
    Joined: Aug 2014
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    Banzai Junior Member

    I sailed on the orange KD650 "Sparta" many times. It's a great boat. The only thing about it is that it is marketed as a trailable boat but actually takes a while to put it all together , what with the tramps and every thing. The builder of Sparta discarded the idea of trailering the boat before he finished building it and put it on a mooring after initial launch. They go upwind pretty well considering, especially in a breeze, and would undoubtably be faster than Tiki 21, since I have overtaken a Tiki 21 with my Duo480 and that is way smaller than the KD650
     
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  12. 23feet
    Joined: Dec 2014
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    23feet Junior Member

    To throw in my 10 cents worth. A great deal is written about Wharrams by folk who have not sailed on one. I have been sailing a Tiki 21 for the last 8 years and continue to be more surprised by its advantages vs its shortcomings (you can see my blog at Wharram Tiki 21 "Little Cat" http://tiki21littlecat.blogspot.com/). The disadvantages are well documented - little or no shelter, small rig/weak light wind performance, low free board. Less is written about the big advantages: shallow draft - you can go virtually anywhere deeper than one foot, and if it gets stuck it doesn't matter because there is nothing to hang up on the bottom; tremendous deck space for the length of boat - I put up a simple boom cover at anchor and have a ridiculous amount of room for a 21' boat; tremendous safety in open water - the low free board, small rig, large beam, and 6 water tight compartments (yes, six) make the boat very reassuring to sail in open water. In regard to the latter, I feel safer on the small Tiki in open water, than I do in much larger boats because I know that it would take extreme circumstances and weather for me to not make it home. If one wants a boat for cruising in sheltered waters in low wind conditions (e.g. San Diego) then the Tiki might not be the best choice. In regard to the much touted poor windward performance, I have several posts on my blog that look at this issue. A Tiki should tack through 50 degrees (or better in ideal conditions), but doesn't like chop and strong adverse currents. But what boat does like short chop and sailing against a tide? I regularly outpace much larger monohulls to windward as long a there is a decent breeze. One thing that goes against the Tiki and may contribute to the legend of poor windward performance is that they are not the easiest boat to sail well IMHO - when you combine this with the fact that many builders a non-sailors then the outcome becomes obvious. While the building plans are expensive, Wharram cats have a high ratio of build starts to completions (that is, many more Wharrams are actually completed), thus it doesn't matter how much cheaper your "superior" building plans are if the boat never gets finished.

    Roger
     
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  13. guzzis3
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    guzzis3 Senior Member

    First let me say I am sincerely glad you are happy with your boat. Sailing is a stupid pass time, completely illogical, and I have argued often over the years that the only valid criteria is that YOU are happy with your situation. If you have ticked that box good luck to you.

    James Wharram has far too often taken it upon himself to tell us all that everyone else is wrong. Take the section on transoms in his design book for example. I personally take issue with the way he talks about things. I'm an engineer and we spend an incredible amount of time cleaning up after architects, industrial designers and other arty types, so anyone with those inclinations make me bristle. The real crunch for me though was when I acquired some wharram plans. I sat down and had a good long look and was properly horrified. They were so so wasteful. Wharram was a trail blazer in the 50's and 60's but he has progressed at a snail's pace while other cat designers have relentlessly pushed the envelope. Better plans, economies in labor and materials. Meanwhile he has continued to charge for every little thing. He gives as little away as possible. Of course it's his business and he can run it as he sees fit, but if you take that hardline approach with your customers you shouldn't be surprised by consequences. I will not give them any more of my money on principle.

    As I say I am glad you love your boat, but every strength you note applies to say Acorn, Janus and any number of other similar size cats.

    It may well be more Wharrams get built by percentage. I guess you could answer with the other argument that Farriers are about the only self build multis that have resale well beyond materials cost, while Wharrams have amongst the worst resale. That's a different thing to build rate obviously, but by what criteria do you judge a designers success ? Ian Farriers plans are the best I have ever seen but a country mile. Is that THE criteria ?

    Anyway the Wharram thing will continue and that's fine. My original proposition was that given his success I don't understand why he has essentially no competition.
     
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