Rapido Trimarans - 2 x New Folding Models Coming !

boardhead

Anarchist
I guess that went down like a lead balloon but it is relevant on this 40' cruiser/racer tri blog - a 2,000 pound payload will sink the main hull by more than three times the number the blue water cruiser was advised.

 
No lead balloons.... just traveling to Manitoulin Island and no WIFI around. I know that our 3,500++ pound addition sank the boat about 4", don't forget that the Amas have 200% buoyancy on this design and they are starting to bear down significantly at this point. We used to lift the windward hull and clear the water completely around 6kn. With all the added weight it takes around 16 before we are skipping the windward amas across the wave tops. We are also 39’ 11” on deck.  But point taken…. I may have a poor memory of what Ian said five years ago.

There is no question in my mind that the F36/39 design does not allow for the sort of stuff that almost every other cruising boat we meet is carrying. We have about ½ to ¼ of the “stuff” most of our friends have aboard and we are still overweight!  Safe Carrying capacity on the F39 is stated at 3,500 lbs.

 

windhorze

New member
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0
CA
As the lower strut swings inboard it lifts the inboard end of the beam up and over the deck permitting the amas to retract inboard with greatly diminished vertical angular change until the ends of the beams meet on centerline - no crud on the ama topsides!

Clever geometrical shuffle but that marina concession still has it’s weight and integrity penalty, gotta comply with market demands and if that’s what they want you have to respect for the customers needs.
sorry, I just don't see the geometry of the folding mechanism working without another articulation point say at the ama's. I'm no M&M, but the model animation just doesn't add up...doesn't sound simple and easy (happy to be proven wrong) and although I can understand the convenience of folding especially on smaller trailer tri's, I would imagine few people that spend 450-600K on a 40 footer will probably want to be bothered with folding such a big boat vs throwing down a few extra bucks for an end tie...how many Dragonfly 39's or Contour 34's do you see folded into slips...just some thoughts...

 

boardhead

Anarchist
Pretty simple really from an articulation standpoint but at what cost in weight, maintenance and dollars not to mention the joys of windage, leaks, ice action, potential for actual bodily harm, and the reduction in platform rigidity - all in the cause of heavier and slower.        Do I really see seven bulkheads plus the stern cap in those amas?

Dont know how far along the tooling is but as a fellow multihull enthusiast wishing to see a bigger, newer, population of these craft out there I would appeal to you to STOP and consult your Heath Robinson records!

 

windhorze

New member
23
0
CA
"Pretty simple really from an articulation standpoint"
you've stated this before, but when I look at the animation I see the aka's changing orientation by 80 degrees and the ama's orientation changing by zero (ok 5 degrees?)...so there has to be articulation at the aka to ama attachment...? sounds not so easy to me...what do you see happening?

 

boardhead

Anarchist
My first guess at the method back in May did not anticipate any change in the geometry between the ama and the aka rather a variation on the geometry of the struts and pivotal points on the inboard end of the ama to the vaka attachment. That arrangement would have been simpler but at the expense of greater intrusion of the akas across the vaka deck.

Now we see, as you point out, a secondary pivotal attachment between the amas and akas. The outboard end of the beams curve downward into wells in the amas with, I would guess, a pivot pin at the tip near the keel and secondary pins sliding in radial grooves set in the faces of those well bulkheads just below deck level.

I am almost certainly off on the details but that’s the concept, smart but calling for quite a lot of precision engineered parts that even with careful material selection will be shorter lived and less reliable than a rigid attachment - and much heavier.

Anyway, Paul has been teasing us since he announced the “no crud on the topsides” system, the finished product will reveal the details but I would not expect a stampede of builders conflicting with the patent, if it is granted.

I remember the Walker Wingsail too well, it ended badly so I hope these guys are not headed down a similar path. I personally like the KISS approach.

 

Wess

Super Anarchist
Now come on Wess  - are you gonna disassemble that puppy and trail her out west for your PNW cruise!
LOL, would hope to have checked that box with the current boat before we get the next boat which is likely 5-10 years down the road.  But for sure Rapido - along with a select few cats (TS, Daz, etc..) - are on the short list. 

Would love to be able to stick with a tri so am keenly interested in Rapido. 

 

EarthBM

Anarchist
I would imagine few people that spend 450-600K on a 40 footer will probably want to be bothered with folding such a big boat vs throwing down a few extra bucks for an end tie...how many Dragonfly 39's or Contour 34's do you see folded into slips...just some thoughts...
I see some skepticism here about the need for folding tris. I think it might be regional. In the areas where I sailed, Puget Sound had enough protected coastline to keep my Dragonfly 35 unfolded on an end tie, So Cal and South Fla not so much. Europe apparently is even worse, at least in places where you want to be. I estimate the ability to use a mono slip for a 50’ tri is worth  about $500-1000 less in monthly docking costs in most places where the buyers with $$$ are. That’s $6-12k per year. Taking a conservative 10-15y useful life, the savings are between $60k and $180k. So as long as the system adds less than that to the cost it's worth it.

FWIW, keeping my DF folded was not a factor in deciding to take it out sailing at all. Having to drive an extra half-hour to a marina with a side-tie would’ve been.

 

boardhead

Anarchist
I see some skepticism here about the need for folding tris. I think it might be regional. In the areas where I sailed, Puget Sound had enough protected coastline to keep my Dragonfly 35 unfolded on an end tie, So Cal and South Fla not so much. Europe apparently is even worse, at least in places where you want to be. I estimate the ability to use a mono slip for a 50’ tri is worth  about $500-1000 less in monthly docking costs in most places where the buyers with $$$ are. That’s $6-12k per year. Taking a conservative 10-15y useful life, the savings are between $60k and $180k. So as long as the system adds less than that to the cost it's worth it.

FWIW, keeping my DF folded was not a factor in deciding to take it out sailing at all. Having to drive an extra half-hour to a marina with a side-tie would’ve been.
    But would a much faster 35 footer been worth the extra drive?

 

EarthBM

Anarchist
    But would a much faster 35 footer been worth the extra drive?
Yes it probably would.
But the weight penalty from a Farrier-type folding mechanism is probably not that great. Dragonflies are heavy boats because their specific sideways folding mechanism requires overbuilding in a few areas and very heavy stainless waterstays. FWIW, I think all of that could be lightened a lot with proper numerical analysis, experimenting, and modern materials expertise. But since there also was a lot of nice wooden furniture, stainless steel fuel tank, etc. it mattered less.

The Farrier/Rapido folding system is fundamentally clever because it takes advantage of the fact that the effort on amas is strictly one-directional.

With that said, I agree that the execution would have to be near-aerospace-like, as I mentioned before in this thread. Especially with ama foils. 

But then again, this is 2019, we have space rockets landing with the pointy end on ocean platforms, monohulls fully foiling (multi in multihulls is really redundant if you think about it), fully rotating wing sails with computer-controlled hydrofoils, etc. 

Folding boats is not a new concept — Odin’s boat Skidbladnir could fold and be carried in his pocket...

 

eric1207

Anarchist
851
290
Seattle
Funny you should mention that.  I was just day dreaming what one of those, past-prime, huge ocean single hander racing tris costs and how hard would it be for an old guy to single or double hand with smaller sails or a few extra deep reefs.   The dream was; find some rural (not crazy expensive) waterfront say in BC, Baha or up some East coast river where you could cludge up a big hillbilly trailer and use a tractor or 4WD,  to haul it out on the beach.   When you've had enough seasons there, then sail it somewhere else, .....FAST,.... and repeat. 

Upon reflection I think a 60'er would be better than the really big ones.  Hmmm... Upon SOBER reflection I think that its just a crazy dream.  Back to real life.  Reality is; my F31 is a good boat for me & the Salish.  But if I had the cash the Rapido would fit the dream quite nicely.

 
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Veeger

Super Anarchist
The 40 gets me thinking!  The 50 is a technical and pragmatic solution to the issues of a cruising trimaran (but not so much soul) , and the 60 is the epitome of speed and beauty.  Would love some nice passages on the 60!  But the 40, now that could almost be do-able for a guy like me who has to consider he'll be sailing the 'next' boat even after hitting the 70 year mark.  Not there yet but the 'next' boat will take me there...

 




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