Minuet Yachts: a 2m fun boat-can the design be improved?

Here is the current state of things on the sail inventory. I think I will be moving the reefing points down one panel, if I go with the flat top main.

UW stands for Upwind
DW stands for Downwind.

The gaff rig and short mast I already made, but the cut is not very good so I will be adjusting it.

CT249- notice the production rig, that is what real ones over in England use.

Thanks! As of today, It's a registered watercraft in the state of Utah, and 70 lbs of lead is on its way here as we speak.

So you suggest attaching the jib halyard straight to the mast and leave the top 4 feet or so completely loose-luffed, so the luff pocket only goes up the first 2/3rd's of the mast? There are no shrouds, it is an unstayed windsurfer mast, although I would like to add some sort of flag halyard at some point.

Which numbers are you referring to? Sail area? Righting moment? I haven't really done any except calculating righting ballast moment in a knockdown... In fact, I don't even know the sail area...

 

If you hate to chop the mast, leave it as it is; I was just expressing some thoughts.

The halyard block could attach to the mast itself if you just leave a hole in the luff pocket, just like a smaller version of the hole that windsurfers have where the boom attaches. Of course, you won't be able to reef, but the modern short-overlap fractional rig is a marvel; with good tweaking you can cover an enormous wind range under full sail.

Leaving an unsupported luff above the hounds on a windsurfer rig will point load the spar and be aerodynamically inefficient IMHO. They can handle 18" or so of point load (i.e. unsupported span between the head of the sail and the mast where the 'turban' is) easily but I have no idea how much more than that would be OK; it depends on the construction and carbon content of the mast. I've known guys to break three Formula masts (very high tech but subject to enormous loads from downhauls that had 13:1 tackle leading to a winch!) in a single day just while rigging!

By the way, will this boat ever need a Code Zero? The 2.4s and Illusions run square in light stuff as far as I know; a boat like this is far too slow to build up apparent wind.

 

What do you mean by the hounds and turban? Not sure I see it. The mast is full fiberglass, so carbon content of 0 I believe. I really wanted to be able to reef, but I'd rather have a good solid rig. My largest concern is that it will be overcanvassed over about 8 mph of wind. I will be sailing in either 0-6 mph or 10-20 mph of wind, the band in between is not very common.

In this case the purpose of the code zero (solid red) is a very light wind upwind sail. I may not go that route, but for now I think I'll be just doing the working jib and A2 spinnaker(fractional headsails).

 

The sock should extend to the top of the mast. You can step the mast in a receptacle in(or on) the deck. Leave the shrouds and forestay(you will need them) inside the sock until you start pulling the sail up with the halyard. As the hole you've left for them starts to go by, reach into the sock through the hole and pull the shrouds and forestay out and continue to raise the sail. Just think about it carefully for the full rig and reefed rig(s). A fiberglass windsurfer mast will very likely be too flexible and will-at least-need shrouds and forestay.
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Did you calculate center of buoyancy and displacement? I once built a small kayak and because I thought I was so damn good I didn't need to do the numbers and wound up with a pretty boat that wanted to roll over. You need to do the basic calculations.Without doing the calculations it will be just pure luck if the boat floats on her "designed" water line and not trimmed down by the bow or stern with you in it. Get a copy of the latest revision of Skenes Elements of Yacht Design-it's not difficult to do the basic stuff. Not knowing sail area is not a good thing-without knowing that you can't knowledgeably know where your reef points should be. And you'll have no idea if your unstayed windsurfer mast will support the rig. Just guessing, but I doubt that it will do it without shrouds without too much bend for your tall rig. Are you going to make the sails? In your "medium" picture above you show a small main with an asy spin(or code zero?)-you won't be able to sail to windward very well with that sail as your only head sail?
One of the good things about a tall square head is that it is really simple to depower just slack off on the vang but you'll need a powerful vang and down haul to set the sail right.
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There is a test you can do after you determine the sail area and center of effort of your rig: put the mast on two saw horses-one near the bottom-one near the top(no shrouds or forestay) or one at the hounds(point of attachment of the shrouds and forestay)-say 75% up from the mast heel. Then determine the max pressure you can sail in by placing weight hanging from the mast at the location of the center of effort of the whole rig. In the old days boats were designed to sail in 1lb per sq.ft. pressure before depowering or reefing. Today a F18 cat will sail in 1.8 lbs per sq.ft. before having to depower. I would start on your tall rig with around .33lb's pressure per sq.foot-so if you have 50 sq.ft that would be 16.5 lb. at the CE. Be careful when adding weight so you don't break the mast. Get the Skenes book and on,approximately, page 267 are wind pressure co-efficients that tell you how much pressure for how much wind. They are only useful for estimates but are much closer to reality for a displacement monohull. Regardless who is building and designing your sail, the bend characteristics of the mast are essential because the luff of the main has to match mast bend. If your mast bend is excessive even with shrouds and forestay you may need to add a spreader and lower shrouds. Covered in Skenes.

 

I see. It's really designed to run completely unstayed, so I will probably just switch to the short aluminum mast and gaff rig if the windsurfer one is too flexible. I was a bit concerned about the mast at first, but the windsurfer mast is surprisingly stiff, not nearly as flexible as the carbon ones I've seen. Hopefully it's just as strong.

As far as the hull design, It was all done in Free!ship so I have all the calculations and already maximized the design for better stability and the proper displacement given the total weight, I just haven't done anything with the rig to speak of.

I will be making my own sails sometime this winter.

As for the sails:
Solid red is a very light wind jib for upwind sailing.
Red and black stripes is a very light wind asy. spin for downwind sailing, possibly dead downwind, wing on wing with a pole, like the old balloon jibs from the 1800s and 1900s.
The white jib is a medium air working jib, and would probably be thrown on if I'm lazy.
The black, white, and red asy. spin is a more typical spinnaker.

The gaff main is already made, and tested here:

If I do convert it to stayed, I'm going to have to add wood in the correct spots as the chainplates would just rip out of the cardboard and fiberglass. I would also probably have to add a track in the mast. If I go that far, I would probably just lay up my own full carbon mast or something like that. I will be sailing it on a gaff rig for at least a year before then if the unstayed one doesn't work.

Here's the gaff rig, minus headsail:



Edit: I just ran a rough estimate on sail area, I got about 33 sq feet on the full flat-top main, and about 15 on the white working jib. That's about the same as the lower-medium windsurfer range. What effect would a little bit of mast bend have on the sail shape? Just uncontrollably open the leech up top?

 

If the gaff rig is the one in your render(can't tell much from the picture) it will probably cause severe weather helm.

 

My thoughts exactly, Even with a large jib, I think It needs to be a bit more forward. What do you think of those numbers? 33 and 15 sq feet?

Not sure if I made it clear, I intended to be able to completely raise, lower, and stow all sails while underway. All the options in the render above except the production rig and gaff rig are just different sail combinations to be flown on the same rig. The middle ones simply show it with the main reefed. The multitude of headsails is simply to adjust to conditions while underway. Ie: Drop working jib and replace with 2A(red,black and white spinnaker), if wind dies drop 2A and put on 1A (striped red and black), etc...

 

I just realized I'm going to have a hard time holding batten tension with a luff pocket, so that somewhat ruins that idea. I'm now looking at a simpler high-aspect battenless or minimally battened(leech edges only) marconi rig. That will be easier to sew well too. Mast bend shouldn't be as much as an issue. I think I will use the windsurfer sail it came with as a template. It shouldn't be too hard to set up a loop inside the luff pocket to attach the foresail halyard block to. I would go with a gaff but I really don't want strong unsupported concentrated loads on the mast, like at the throat and head. With a zippered luff I can still reef just fine, and do all that stuff.

 

Progress!



And next is pouring the lead in the form(after removing the wood board)


The board does look a bit long, I might shorten it a little, maybe 6 inches.

-Peter

 

You have a lot of fairing to do and when you're finished the boat should look great.
The daggerboard in the last picture looks much further forward than it does in your illustrations-if you use those rigs in the positions shown and the board where it is shown in your picture I'm afraid you'll have serious weather helm.
Be very, very careful with the lead!
Good Luck!

 

Yep, I'm raking the daggerboard back as far as it can go in the slot, i may cut the top corner to rake it back more. The center of the board comes out directly below the mast, just like in the real minuet, so hopefully that will help. I'm also focusing on maximizing headsail area and minimizing mainsail area. I'll also balance the large rudder so that should help control it. I may make the daggerboard a little shorter. I am also considering a bowsprit and double headsails.

 

Storm sails done!

I've settled on the short mast and gaff rig for working, and i can lower and raise all sails on it. I may make a tall rig with the windsurfer mast for racing, but it wouldn't be removable like the gaff setup.

Anyways, for the gaffer, here are the storm sails all done The hull is basically done as well.


Off to go make a Genoa now!

 

I've toned down the gaff main and focused more on the genoa. Here it is with an asymmetrical spinnaker(basically just a genoa with a ton of camber)



I'm also worried I won't have enough sail area for light winds, what do you guys think?

 

Almost done!



Keel poured!

 

Epic!