1.5 Nacra in the making

I am definitely following this! I am concerned with torsional stiffness but hey, should be a good story at least.

I am concerned with torsional stiffness.

Have taken care of that, by use of waterstays to minimize bend in the oversized beams, almost double wall thickness compared to Nacra beams. More info in my FB-group in the signature below.

Todays work in the image, cockpit floor tomorrow.

Edited by revintage on Sep 07, 2023 - 05:38 PM.

What's the objective, more speed? With a bigger sail or under stronger winds?
Or is it more about the process than the end result?

Andinista wrote: What's the objective, more speed? With a bigger sail or under stronger winds?

It is to get an all together bigger, more seaworthy boat, 5.8x4.8m. Larger rig and a lot more RM. Large enough to carry a small outborder when doing longer trips. No need for trapeze for the old man. Should be a little slower at light wind, equal when sailing with the center hull just lifting and capable of higher winds. Rudders on amas and daggerboard on center hull.
Time will tell......

Edited by revintage on Sep 08, 2023 - 02:46 PM.

That’s cool
So like a Cadillac. Or maybe a Chevrolet C15 🙂

Edited by Andinista on Sep 09, 2023 - 08:23 AM.

Andinista wrote: That’s cool
So like a Cadillac. Or maybe a Chevrolet C15 :)Edited by Andinista on Sep 09, 2023 - 08:23 AM.

A 250kg convertible :-D.

Question is what to build with the remaining 5.8 hull and the F18 rig?

Edited by revintage on Sep 09, 2023 - 09:54 AM.

Kudos for building this.

revintage wrote: by use of waterstays to minimize bend in the oversized beams, almost double wall thickness compared to Nacra beams.

Wow - those beams are massive.
This is a great project Lars!

Wow - those beams are massive.

This is the design I have choosen, note I use two shrouds/side connected to the same point as the waterstays, to make the platform as stiff as possible without loading the 5.5 hulls:

This is the inspiration for the rig, where I have marked shrouds/waterstays in red:

Edited by revintage on Oct 01, 2023 - 05:33 PM.

At nearly 16 feet wide (4.8m), you are obviously planning some sort of Ackerman steering method.
Will you achieve this by bending the tubes coming from the castings to the tiller crossbar?
The Dart 18 my friend sails has this.

Edited by klozhald on Oct 02, 2023 - 01:25 PM.

Will you achieve this by bending the tubes coming from the castings to the tiller crossbar?

Have a pair of Marstrom Tornado rudders. Will add adapters at the tiller ends to get a toe in of 10-15 degrees.

Interesting Ackermann paper:

https://docplayer.net/44232169-Efficient-steering-of-a-catamaran-using-ackermann-principles.html