a better tiki 21

Angélique · Jul 19, 2019

To take the idea of one outward angled board like on the Slingers and Slider to an extreme, imagine the below NACRA F20 FCS with only one board which is pointing to the outside . .

P.S. - the F20 FCS (Flight Control System) owner's manual pdf, the primarily dagger foil fore-aft rake and height settings are on page 23-24 of 28.

guzzis3 · Jul 19, 2019

Angélique said: ↑

Guzzis, that's 2 × Slinger in post #166 (not Sliders), the nearly 16' Slider is in post #178, but I see what you mean...

— anyways, to avoid confusion, never give a bunch of designs nearly the same name ! —

After posting the NACRA 5.2 in post #176 I've looked back at the Sliders, and indeed got the same impression for the small one.

But then I got hung up by both of them having only one outward angled board shown, which when on the lee side gives an undesirable downforce on the leeward hull, and when on the windward side gives an undesirable upward force on the windward hull, which also looks to be the case on the Slider.
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Sorry I was so focused on the numbers I missed the names

Angélique · Jul 19, 2019

Oh well, just saw in the quote I've made the same mistake in the middle, not so easy two Slingers and one Slider . .

redreuben · Jul 20, 2019

Angelique, sounds like you're in a cocktail bar !

Angélique · Jul 20, 2019

Damn, busted again, I've just posted how to make Diesel / Mazout / Broadway (thread: Songs about Boats, in post #346), and now I'm caught on two Slings (1 - 2*) and a Slider . .

* how to video

redreuben · Jul 20, 2019

Oh you're from Belgium !
It all makes sense now.
Proost!

dsigned · Jul 21, 2019

guzzis3 said: ↑

That is really interesting. I don't think I know a single person under 50 that sails, so that's reassuring.
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Myself and my brother in law both own beach cats. If it wasn't for going through a divorce I would likely have gone down to Texas for the Texas 200. I think my generation (millenials) are much "cheap"-er (as in frugal to a fault) than our parents (although my parents are also quite frugal), with some exceptions in certain areas. We also tend to be "green", so the "have fun for free" aspect is appealing. And the Wharrams definitely have a "vintage" feel to them, which is a plus.

dsigned · Jul 22, 2019

waterbear said: ↑

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.

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.

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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After looking it over, it seems to me that the bend in the beams would allow for water to drain to either side (with the deck following the beam) in the decking between the hulls.

dsigned · Jul 22, 2019

guzzis3 said: ↑

Dejay:

I laughed a little that you get mad at the "artsy" types and their idiosyncrasies but you yourself want to build a boat just because it has a certain style - even though there is plenty of more utilitarian and better engineered competition out there

I don't have a problem with style at all, I have a problem with people who can't reconcile style with practicality. Like an architect who puts the hot water system in part of the house where it can never be removed or replaced and industrial designers who have no clue about ergonomics. I've seen architects design buildings that cannot physically stand up and their arrogance unfortunately gets them into positions of authority, wasting tons of money and then an engineer has to come in and try to clean up the mess.

People talk a lot about dagger boards being more efficient but the other reason they have supplanted centerboards to a great extent is that you CAN raise them and maintain steerage. Ian Farrier went to some length to make a kick up daggerboard rudder for precisely that reason. I live and sail in queensland where the waters are perilously shallow, reefs are everywhere and in many places currents are tremendously strong. I am as aware as anyone of the benefits of shallow draft and I've always been a fan of V hulls for the reasons you cite, but they are most certainly NOT the only path to a suitable craft.

A tall rig can, and should, be shortened for the conditions, and I think it's generally accepted now that the paranoia about high freeboard is much overstated.

But you are again missing my point. While Wharrams are not great sail boats I think they have their place. That's why I was musing about the tiki 21 in the first place. I guess I have not made myself clear so here goes another try.

I bought Wharram study plans and was surprised at how poor they were especially given the cost.

I bought Wharram build plans for 2 designs and was shocked at how badly they wasted labor and materials.

I looked at the cost of Tiki21 plans and am shocked at the cost.

Given Wharram is quite successful at selling plans I am surprised no one has done something in the same vein, not a direct copy just something similar in style while taking full advantage of "modern" build techniques and attention to detail, then sold the plans at a lesser cost. I would think there would be a solid market for that product. I am specifically NOT talking about a design for a "modern" cat as that has been done very well many times over, rather something in the vein of the Wharram but moved on somewhat.

Anyway..
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To riff on your idea a bit:

I fovor a a low freeboard for less material and less weight, double-ended (or very close to it) demountable hull cat in the ~21 ft class. Preferably that can be made entirely from scratch. Being the somewhat sheepish owner of a Prindle 16, I think the idea of beachcat mast and sails is much nicer than the reality of beachcat sails and mast. The Prindle mast is 20-something feet and is entirely too long to be raised comfortably by one person (or really even by two unless you have the pin for the mast step, which I do not). I've been temped to cut off the top 5ft of mast and sail, and I actually think that might make the boat more fun. I'd be tempted to do a balanced lug or a junk rig.

For going upwind, I like the Kohler vortex generators, or possibly a single swinging board (lee or center).

I would skip the full vee hull. I really think it's unnecessary as narrow as the hulls will be. Honestly, I think I would even make the ends into little scow bows. I think the knife edge bows are likely not as necessary as they are popular.

My favorite option posted here so far is the Mr. Toad skiff cat. Switch to a simpler rig, do the Kohler vortex generators, and some nice large low aspect ratio kick up rudders and I think you've got your boat.

Mark Waters · Feb 11, 2020

23feet said: ↑

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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Roger,
Is there any chance I could swing by and check out Little Cat one of these days? I'm in Sacramento but often in the Bay Area. I'm just about to pull the trigger on purchasing the plans and starting to build a Tiki 21. Please contact me at rawneyrom@gmail.com if that's a possibility. Thanks,
Mark

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a better tiki 21

Angélique aka Angel (only by name)

guzzis3 Senior Member

Angélique aka Angel (only by name)

redreuben redreuben

Angélique aka Angel (only by name)

redreuben redreuben

dsigned O.R.C. Hunter

dsigned O.R.C. Hunter

dsigned O.R.C. Hunter

Mark Waters New Member

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