Hobie 17 Amas

[zigzag]

It has been previously stated on the forum, perhaps by Chris Ostalind that a hobie 20, amongst others like tornado are possible donor catamaran hulls for a trimaran. I assume the mast and sail are included. Does anyone know if Hobie 17's have symetrical hulls and can be adapted to build a tremolino type tri ? Are there any problems with using the rig as well?

[Meanz Beanz]

They used the Hobie 16 .....

I can't see why the 17 would not be fine.

[waltm]

I believe the 17 was a single handed boat, symetrical hulls with centerboards. Not nearly as boyant as a 20.

[Meanz Beanz]

But as much as the 16 which the tremolino used so it is doable if you really want the 17.

[zigzag]

I have been offered hobie 20 hulls and rig in restorable condition at a very fair price and am looking at a trimaran 18'/19'AKA conversion option. What is the comparison between hobie 17 and 16 re. buoyancy? The 17 seems to follow more currently acceptable lines ? The centreboards could be an optional asset?
Sail area is smaller but could be compensated by bigger jib? Comments appreciated.

[zigzag]

Correction, the offer is for 17' only.

[Chris Ostlind]

The beams on the H17 have two different angles of entry where they join with the hull decks. This makes the process of connecting the amas to a vaka hull a lot more complicated. I'm not saying it couldn't be done, it will just take a lot more thought and have to be worked-out before you start building the main hull.

Zigzag, you've already seen this, but elsewhere on this Multihull discussion area, (New Take on Tremolino http://www.boatdesign.net/forums/showthread.php?t=17094) I have shown a design study I did that makes use of Nacra 5.2 hulls on a 20 LOA trimaran. The 5.2 is also 17' in length, has nicely shaped hulls with the volume biased forward, modern sandwich laminate construction and they use a pair of straight, 4" aluminum extrusions for beams.

This Nacra 5.2 hull design makes life a lot easier for creating beam mounts and folding mechanisms for the main hull. It also makes for pretty straight forward alignment of the cat hulls relative to the main hull for optimal performance on the water.

The answer to your question about whether the cat rig is functionally OK for the proposed trimaran is... It will work just fine. So will one of the rudder assemblies and virtually all of the sailing control hardware from the beach cat.

I have also explored this same idea with the use of a 19-20' beach cat in the design study called the Zona 65.
( http://www.boatdesign.net/forums/showthread.php?t=10076&highlight=z65 ) The Z65 is a bigger boat in that it has a functional cabin environment, a fairly roomy cockpit and folding system for the amas (cat hulls)

[zigzag]

Chris, , thanks for your reply. My problem is that in Hong Kong there is a limited supply of run down beach cats. The H17 is available. Your Z65 is perhaps too big for the hobie amas and sail area is only a total of 200 square feet. Can the zona be scaled down?, Does the zona have rounded bilge or narrow entry and flared?

[GOTTABSOMEWHERE]

Zigzag

Hello Hong Kong ................love That City..........was There Many Years Ago

I Have A 17 Hobie Cat That I Am Presently Mating With A 16' Dory
It's Going Together Just Fine............................i Am Fabricating A
Nest Or Saddle For Both Beams For Strength And Getting The Proper Elevation Of The Floats. Going For About 4" Higher Than Dory Bottom. Just Guessing As All The Tri's I See Are Higher ???
Alsooooooo......the Nest/saddle Will Be Fabricated So Ik Can Remove The Cat Or Put It On Whenever The Mood Strikes Me.
Not Changing Anything On Hobie Cat Still Have Fully Battened Sail, Jib Etc Etc.
Can I Be Of Any Assistance /