Sharpie Design Build and Sail Rig Alternatives and Modelling

In this my third video on the designing, building and sailing of my 23ft/7m Sharpie inspired design, I go into the different rigs I considered and I explain the model I tested to give me confidence, the fusion of a Ljungström Cat Rig I've designed, will work.
Building is still going well and the next video will be on the building of the temporary frames.

[@Ericviking2019]

Interesting

[@michel4765]

Hello,
i would go for the single squaretop sail setting conventional with a halyard in the groove or on slides for the following reasons: 1, when reefing you keep your good sail profile .... you loose it if you turn the mast, lower windage too, 2. you can bond the wishboom to the mast, eliminating two lines, 3. sun cover over the sail when not sailing is easier, 4. for downwind work you can use a more effective gennaker instead of having a second, useless, sail in the mast most of the sailing time. A double sail is 50 unnessesary sailweight way up, reducing righting moment.

[@KarlFullerNZ]

Thanks for the feedback!
Agree with you about having the luff of the sail in a track or bolt rope groove because it would give a better profile when reefed.
Probably will go ahead with trying the wishbone support as I planned it given the thought time I've put into it! You still need a topping lift for the aft of the wishbones so still need a swivel at the top. I can't imagine the drag being too bad as I'll use thin Dyneema.
I take your point about the extra weight of an extra sail a lot of the time but I'm thinking upwind you'd get the potential of a good wing shape, a very rudimentary version of the Sail GP sails so it could as you can see, it's swings and roundabouts.
It may turn out some of my ideas might not work but part of the incentive for the project is the satisfaction of the inventive side of it.

[@dominictarrsailing]

very interesting rig! that's gonna go hard downwind! I think it will go well upwind too! I never knew you could use upright battons like that! (actually I looked and couldn't find anything else about that in a furler apart from this video)
tbh, I am a slot effect skeptic. they stopped making biplanes because it has a lower lift to drag ratio. they also dropped wire stays and went for cantilevered monoplane, because better lift to drag ratio! like your rig! though, speaking of l/d why not have a support that comes up and holds the boom, instead of the wire from the masthead and topping lift? then you'll have a fully clean airflow. or even a compressive vang thing, I think that would have much less aerodynamic problems than a topping lift

[@KarlFullerNZ]

I appreciate your suggestions, you've been thinking about it!
Yes, there's not many around with vertical battens, here's one
th-cam.com/video/lJ_2IlF73dA/w-d-xo.htmlsi=bDOFHy2E67rzUpYI
I have similar views about the slot effect in regard to yacht sails when comparing them to the evolution in plane wings. It's going to be interesting to see how she goes.
Have given what you're talking about in regard to holding up the wishbones a lot of thought and it has been done in a manner you're talking about, like this example but it uses rollers on the sail around the mast, to opose the outhaul tension. It works but it's not a solution I like and rollers over a sail track would not be great probably.
th-cam.com/video/3BmmrgzmTHs/w-d-xo.htmlsi=BG7jeHx3qGVJA_a4

[@VLOGS-skyun]

great
Very good
But I personally prefer solo ocean sailing. So it is even more important to reef the sail quickly. So I personally prefer junk rig or gaff rig.

[@KarlFullerNZ]

You certainly get quick reefing with a Junk. It's going to be interesting to see how practical and quick reefing with this rig will be.

[@Cptnbond]

It's another excellent episode. I appreciate how you discuss various options. The value of switching your design work between small models and computer design can be insightful. I spend time modeling the build process for my work. What is the mast height of the single sail solution?

[@KarlFullerNZ]

Good to get your feedback thanks!
I agree, if you're trying a combination of ideas, in my case attempting to blend the best of a Cat Rig and a Ljungström Rig, there's only so much that can be done in a CAD program, in your head or on paper, before a model is required to clarify things.
For the single sail solution, the mast height above deck is 9.3m/30.5ft.
What line of design work are you in?

[@Cptnbond]

@@KarlFullerNZ Hi Karl, thanks for taking the time to answer my questions, which I appreciate.
I'm considering a sailing boat in the 8 to 10-meter range. For the moment, I am designing and modeling it as an aluminum hard chine type of design. In this way, any plywood boat design can be 'converted' to a metal-based hull. Why aluminum, you may ask? My objective is to make it a capable high-latitude yacht (think Svalbard in the Northern Hemisphere), and secondly, the project will improve my aluminum welding and building skills. My first iteration will be a much scaled-down version to identify practical building issues and the best approach for the final build. The boat should not be any larger than it can fulfill its function, which is a good approach from a DIY and economic point of view. It's fun and encourages me to expand my knowledge. Cheers.

[@KarlFullerNZ]

@@CptnbondIt'll certainly improve your welding skills! I have built one Alu 39ft David de Villiers design and it turned out really well. sites.google.com/site/karlfnz/liso39
I agree, build just enough for what you need, too many yachts don't get finished or sailed because the owner is too dependent on crew. Having designed, built and sailed a 60ft steel yacht for myself, I can testify to those comments!
I found a big part of building an Alu yacht is the MIG welder. If you can afford it, try to get a twin pulse machine, it makes a big difference, especially for positional welds. Also, everything must be kept very clean and draft free. It's way too easy to get porosity!
All the best for your project!