Lee wants a new trimaran design...

[Lee.007]

Ok guys, thanks to the help from many of you on here, I built my first sail boat ever, the Misty Sunrise. I had a blast doing so and also sailing it is exhilarating. Now I am addicted. Is there a rehab facility somewhere?

So, I need to build another boat so the wife and or family can tag along. I want it to be small and trailer-able like my first one. I will design in hinged akas to make it easy to fit on the road, so overall width does not worry me. I probably won't start construction for another year, so I have plenty of time to research and design so I get it right. Or closer to right than my first one anyway. Here is the list of what I want:

*Trimaran multi-hull

*Efficient enough hull design to paddle at 2.5 to 3 knots comfortably

*100 to 120 sq feet of total sail area, probably Bermuda rig for simplicity, maybe a jib too.

*21 feet max length overall

* Beachable with flip up leeboard and flip up rudder

*Seating for two minimum

*Capacity to haul 800 pounds of people and or camping gear

*cedar strip built, or stitch and glue

*150 to 200 pounds max boat weight

*A little more freeboard than a kayak so I don't get soaked, but I want the long and narrow kayak shape for the main hull, with a flat or slightly narrow stern

*Amas that displace at least 200 pounds each so I can step off a dock onto them and they don't sink.

I have looked at the CLC Shearwater double, Chesapeake tandem and triple, and the Bootlegger tandem, but they don't seem to have the extra freeboard I am looking for. I also am eyeing Nick Schade's Great Auk. But if I used them for the main hull, I want bigger amas than the clc sail rig.

I once read an old book that had a Glen L design in it called the "Folding Schooner". I think it will be too wide, and a little too long, but it has the right idea.

SO, Does anybody have any plan or design suggestions that meet my very picky and possibly unfeasible requirements? Thanks in advance for your thoughtful suggestions!!

Lee (commander of the Misty Sunrise)

[Touchatout]

As your examples that canoe is too small for your need.
But she is thinked to be used with her "trimaran kit":
http://www.kaamosboats.com/toucanoe.htm

On same site you'll find a bigger "family canoe" but not with "trimaran kit".
Anyway they can fuel your brain...

[swoody126]

more "fuel for the brain"

https://duckworks.com/trilars-plans/

sw

[NeilMB]

If you want strip planked, Gary dierking's ulua is a winner and can be stretched as far as 24' https://duckworks.com/ulua-plans/

If you're okay with less elegant hull forms, the rest of his designs are just waiting to succeed https://duckworks.com/gary-dierking/

[JimD]

Small trimarans | Lunada Design

Some ideas from Lunada. But I doubt any tri with proper sized outriggers for sailing is going to paddle decently. And your weight restrictions might be a problem too.

[FishoutaFlorida]

I probably won't start construction for another year, so I have plenty of time to research and design so I get it right. Or closer to right than my first one anyway. Here is the list of what I want:

*Trimaran multi-hull

*Efficient enough hull design ...

SO, Does anybody have any plan or design suggestions that meet my very picky and possibly unfeasible requirements? Thanks in advance for your thoughtful suggestions!!

Greetings Lee,

You know when I look at your list here, I'm seeing design parameters that you have found need to be applied to get what you want. And I'm pretty sure that you've already searched the market for a potential candidate. But these comments also look a lot like a start to a planning project manual that could just as easily be applied by yourself to generate a design!

Based on your existing boat, you've learned a lot! If you were to find another boat design, it would have to perfect for you to build it exactly as shown on the plans. It looks like you've got a lot of CAD documentation out there, so no matter which way your design went, you would have a head start. And with the folks who've watched and contributed to your first project, well there is tons of experience and knowledge out there to bounce ideas and refine the end product. Just my 2c worth, but you've got such a nice looking boat, have a lot of applicable baseline drawings, a list of your specific objectives...design what you want and build it! I know it's problematic to start at the beginning, but your attitude, ingenuity and stick-to-it ways have impressed me and I'd like to see what you could come up with.

Plan B? Get someone else's design and do the best with it, which would probably be pretty good as well.

Thanks Lee! I'll be looking to see which way you decide to go!

Eric

[Woxbox]

OK, Lee. I'm going to take another shot at convincing you that the Seaclipper 20 is the right fit. Check out this video.

[Stora Le]

Is this too small for you?
https://bandbyachtdesigns.com/sailboats/minitrimaran/

Viktor

[Lee.007]

OK, Lee. I'm going to take another shot at convincing you that the Seaclipper 20

I am tempted Dave. But from looking at the rigging and the way the mast is mounted, I am a little intimidated by all that hardware. Looks kind of expensive to build too. I was wanting to do another birdsmouth mast, simple partner and step design.

[Lee.007]

But these comments also look a lot like a start to a planning project manual that could just as easily be applied by yourself to generate a design!

Thanks for the vote of confidence Eric! And yeah, I am really close to just rolling my own.

[Lee.007]

I am on staff duty tonight(All night duty where I sit in the battle captain's chair and answer the phone in case the world explodes) and have plenty of time to stroll the internet and look at boats. The more I look, the more I think I want a marriage of the Seaclipper 16 and the Slingshot 19. I just might have to buy plans for both, and do a kit bash. Or maybe just roll my own completely. Thanks to all for the brain fuel!!

I like the ideas behind the flat hulls. I bet it just slides right up on the beaches. But I don't think I like the dagger board idea. I was sailing a few weeks ago, and I was about 50 meters from a clay cliff shoreline, when my leeboard nailed an underwater ridge that was just high enough to drag the leeboard. It was too deep for me to see it though. Luckily, it just rotated the aka a bit in the lashings, and also on the leeboard mounting bolt. I was clipping along at about 6 mph when I hit it, so I think if it had been a dagger board it might have done some damage. Since I don't have a depth finder, I gotta depend on my knowledge of the lake, and my eyeballs. There was no buoy or anything marking that ridge. I wonder how many power boaters have lost their prop on it.

So do ya'll reckon the Seaclipper would be alright with a leeboard??

[Gary Dierking]

Take a stroll through the last 14 years of my blog on sailing canoes. Anything with one outrigger can also be made into a trimaran. The 20' Tamanu would suit you and can carry four people. http://outriggersailingcanoes.blogspot.com/

[upchurchmr]

Lee,

Perhaps you could help me understand a little more.
Are you planning on having the amas bouyancy low enough that they will submerge rather than the main hull rising out of the water?
Why do you want so little sail area? A Hobie 16 has about 215 sq. ft. There were thousands of them, but it doesn't seem to match your intended use. The Hobie weight would be much less than your maximum, so it would tend to be harder to keep upright than the wide beam, heavy loaded weight and small sail area.
Do you want to keep the seating inside the main hull, or would you put seating area outside the main hull like the Seaclipper 20? Note that a mutihull day sailor needs to allow the crew to move forward going upwind and move aft when reaching. You have already seen the result of placing the crew too far aft and sinking the stern. Performance gets compromised quickly. This is the major concern with the Lightning 19 IMHO.
Stayed masts have been around a long time. Plenty safe and more controllable for performance than a free standing spar, unless you have a sailmaker who will change the sail multiple times to get it right. Yes it will be a bit more expensive, however if you can find a Hobie 16 mast and rig it can be pretty cheap.
How much freeboard?

The folding schooner is much too wide for a multi, unless you just want something to putter around - go slow.

Have you looked at the Trica 540? Meets most of your criteria except perhaps the 800# of loaded weight. And perhaps the freeboard. But you do get the freestanding mast!

I think you are asking for too little boat weight, and too much load. But that is where these studies generally start.

I hope you continue discussing your desires.

[Lee.007]

Are you planning on having the amas bouyancy low enough that they will submerge rather than the main hull rising out of the water?

Nope, not at all. I want the ama buoyancy to be enough so that if I step off a dock onto the ama, it does not sink like the clc amas do.

Why do you want so little sail area?

Its not that I want little sail area, just trying to make sure I don't overpower the boat. I just don't know how much sail area is needed for a given boat weight / payload to make it go fast. Is there a book or website somewhere that tells me that?

Do you want to keep the seating inside the main hull, or would you put seating area outside the main hull like the Seaclipper 20?

Actually, the more I look at the Seaclipper 20, the more I like it. And the wife likes that one too. So probably put the seating on the outside on some hardboard "trampolines". I really like the idea of being able to put a tent up over the cockpit and sleep on the trampolines. I have an old tent I could cut the floor to fit!

How much freeboard?

Enough that I don't get soaked with spray. The Seaclipper 20 looks like it fits that bill.

Have you looked at the Trica 540?

I have not. Never heard of it, so now I have to investigate that one too!!

[Lee.007]

OK, Lee. I'm going to take another shot at convincing you that the Seaclipper 20 is the right fit.

Ok Dave. I think you are going to win. But I gotta build it out of cedar. Not because I have to, but because I want to. I'm just kind of stuck on the natural wood look. Everywhere I go with my Misty Sunrise, people are amazed just because it is made of cedar strips. I had one guy tell me he would swear I spent a million dollars on it. I said, "Nope, less than $1500 actually." He called me a liar. He was drunk, so I didn't take any offense. I just laughed as I sailed away.

I am thinking of using the same construction method I used for my amas. Lay the strips down side by side flat, glue the edges together kind of like hardwood flooring, fiberglass one side, then stitch and glue together with the fiberglassed side inside. I am thinking of making the strips 1 inch wide, and 1/4 inch thick. Glue the panels together long enough and wide enough to cut out the panels needed for the boat.

Can anybody talk me out of using this construction method?

[P.I. Stazzer-Newt]

Eight hundred pounds of crew+gear plus, lets guess at, 400lbs of boat+rig is 1,200 pounds.

Efficient enough hull design to paddle at 2.5 to 3 knots comfortably

I've tried paddling fourteen hundred pounds of boat+crew - and, frankly unless there's six hundred of those pounds actively engaged in paddling - comfortable is not happening - neither is three knots.

[Woxbox]

Ok Dave. I think you are going to win. But I gotta build it out of cedar. Not because I have to, but because I want to. I'm just kind of stuck on the natural wood look. Everywhere I go with my Misty Sunrise, people are amazed just because it is made of cedar strips. I had one guy tell me he would swear I spent a million dollars on it. I said, "Nope, less than $1500 actually." He called me a liar. He was drunk, so I didn't take any offense. I just laughed as I sailed away.

I am thinking of using the same construction method I used for my amas. Lay the strips down side by side flat, glue the edges together kind of like hardwood flooring, fiberglass one side, then stitch and glue together with the fiberglassed side inside. I am thinking of making the strips 1 inch wide, and 1/4 inch thick. Glue the panels together long enough and wide enough to cut out the panels needed for the boat.

Can anybody talk me out of using this construction method?

That should work nicely. If you want to step up your skills and speed up the process, look into peelply and even vacuum bagging.

[Lee.007]

That should work nicely. If you want to step up your skills and speed up the process, look into peelply and even vacuum bagging.

Well, I did look that up. Seems kind of complicated. And more trouble than I want to mess with. Looks like more sanding too. I am sure it makes a nice finish though.

How does it speed up the process? Seems like an extra step to me?

[Lee.007]

Actually, the more I think about it, if I am going to make flat panels out of cedar strips, I could use that peel ply on a flat panel and it might be a pretty easy thing to do. then all of the insides of the panels would be nice and smooth. That would be better than the mess I had on the inside of the amas when I was building my Misty Sunrise. Of course I would need some kind of non-slip on the floor of the cockpit. Thoughts?

[P.I. Stazzer-Newt]

Non Slip?

Lots of advice here
http://forum.woodenboat.com/showthre...-should-I-sand

[Lee.007]

Here is a question I have been rolling around in my head. Understanding that the Sea Clipper 20 may have been designed with the Hobie 16 rig in mind, would I benefit from having sailrite or somebody design a sail specifically for the Sea Clipper, and build my own Birdsmouth mast and boom?

[Lee.007]

so select your scantlings with care.

Oh, dang it, now that I think about it, the freaking mast is 27 feet long. I would have to be really picky about spf boards at the lumber yard. I am assuming you mean straight grained and clear? And since the mast is 27 feet, has anyone made a two-section mast before? How did you connect it in the middle? or was the connection further up the mast where the loads are less? Or is it even worth it to make two sections for easier transportability?

[upchurchmr]

Stayed masts seem complex, but are really easier.
You will get use to a single piece mast quickly.
27' is about the same height as the Hobie 16 mast.
Just think about 200+ sq ft for Hobie verses your reduced size sail (60 sq ft ???)
With the vastly increase size and weight of the Sea Clipper 20 the Hobie sail/ rig will be easily handled under sail.
Plus the sail will set correctly with no "tweaking" by yourself.

[FishoutaFlorida]

Here is a question I have been rolling around in my head. Understanding that the Sea Clipper 20 may have been designed with the Hobie 16 rig in mind, would I benefit from having sailrite or somebody design a sail specifically for the Sea Clipper, and build my own Birdsmouth mast and boom?

Probably, but get the mast and boom done first. Or be super confident in your dimensions. I had salvaged a mast from an unknown boat, bought a boom for a hobie 14' and then used a portion of a crunched hobie 16' boom to get the running gear for my Hartley 14 TS. Then I contacted Jeff at sailrite, developed design criteria, did the design and then modified the design based on his recommendations. Awesome experience for an guy without a clue as well as the well informed/experienced guy.

Yesterday I purchased kits for the main and jib. Very exciting.

Now where is that sewing machine???

[Lee.007]

Ok multi-hull fans, here is my latest hair-brained idea. I want to build the Sea Clipper 20, but it is going to be a minute before I have the space in the garage. So, I was thinking about a smaller boat, to hold 2 people. I saw the free Drifter 16 plans on CLC website, so I downloaded them, but it is kinda small for what I want. But... I am a fairly skilled CAD operator. Soooo... I am thinking about reproducing the Drifter 16 in autocad, scaling it up by say 10 to 15 percent, or enough to make it 18 feet long or so and wide enough for 2 people to sit side by side instead of one behind the other, and build it out of cedar strips that are 3/16" thick x 1" or 3/4" wide. So then I can have a boat for me and the wife, or just me, and one for one of my kids to race against us.

What are your all's thoughts on this idea?

[Clarkey]

Sorry, I haven't been through the whole thread but has this one come up?



https://bandbyachtdesigns.com/sailboats/minitrimaran/

[Lee.007]

No, actually Clarkey I don't think it has. Still kind of small, but it might fit the bill. I kind of like the bowsprit, gives you the opportunity of a large jib. But the telescoping tubes for aka's look expensive. Looks like an expensive mast and boom too. I don't have good access to cheap aluminum here in eastern central Georgia. I didn't see a place to buy the plans on the website, but there was a wicked cool video of the boat. I think maybe they are still working some bugs out of the design and haven't released the plans yet?

[Lee.007]

Ok y'all, check this out. This is the Drifter 16 scaled up to allow 2 people to sit side by side, stretched out to a few inches over 19 feet long. I put the akas on it, but I have not drawn the ama's yet. What do y'all think?


Scaled up.jpg

[Gary Dierking]

I think as you sail more and in different boats, you will come to prefer sitting sideways rather than fixed in a forward position. Sitting out on a hiking seat gives you better visibility all around and adds that very important righting moment. That would mean having a tiller and extension rather than foot steering.

[Todd Bradshaw]

Agreed. That fattened Drifter looks really uncomfortable. Never underestimate the increase in living space that you can generate on a tri with wing nets and if possible, bow wingnets. Naturally, you do need rather large, buoyant amas for them to pay off, but it is worth it if the design allows it.

Lay the strips down side by side flat, glue the edges together kind of like hardwood flooring, fiberglass one side, then stitch and glue together with the fiberglassed side inside.

That's how I built the panels for the drift boat I built back in the '70s. Then I nailed and glued-in little spruce "riblets" on the insides to stiffen the sides, stitched all the panels together, seamed the inside and glassed the outside of the hull. Achieving the natural wood look is possible, but it adds an awful lot of work and head scratching on something bigger than a canoe or kayak. When you combine that with the potential maintenance and covered storage it becomes pretty questionable in terms of whether or not the look is worth it.

The weave inside was not filled, just carefully squeegeed to a really uniform cloth texture. It provided great non-skid and kept the resin to cloth ratio down for maximum strength with minimum weight. The "squeegee" was a small slab cut from a block of ethafoam about 1/2" thick. One of my favorite glassing tools.

drift-boat.jpg

[Woxbox]

What's been said, plus it looks like the two bodies are squeezed in there pretty snuggly. What happens when elbows fly to trim the sheets quickly?

On the performance side, if you lengthen the hull only, you'll get a noticeably better top speed out of the boat than if you make it both longer and wider. Plus, having the bodies sitting out to windward for stability.... There are reasons your suggested arrangement isn't done.

On the other hand, if comfort is favored over performance and you really want first and foremost the feel of sitting behind a dashboard in a wind-powered runabout, why not go for it. But if so, give the sailors some elbow room and approach the project with a realistic view of what performance can be expected. It could be a fun boat.

Iceboats have been configured as side-by-side tandems, but of course there are all sorts of other factors that come into that.

[Lee.007]

Todd and Dave,
Thanks for the advice!

Since I have attracted Todd's attention, I was thinking of about a 85 Square foot mainsail, bermuda rigged, and maybe add a jib. What would you think the max sail area I could safely use would be, Todd? I would like to keep the mast height 22 feet or less. I plan to get sailrite to design and cut me a sail, then I sew it together. I also plan to make the mast a birdsmouth out of SPF lumber from local lumber yards, same for the boom. And I am kind of intrigued by the idea of a bowsprit.

I was tipping over into the idea of putting solid "wingnets" made out of laminated cedar boards, about 3/4" thick, on the akas to sit on, with a back supporting "handrail" wrapping around. Making a U shaped seat with the bend of the U crossing the main hull where the seat normally would be. And y'all are right, those two models I got are average sized 6 foot tall men. It is a tight fit. Some of the tight fit look comes from the fact that the models have their legs spread quite a bit. In fact, if you look closely, the outboard leg is actually sticking through the hull panel.

So I was trying to do something I could build fairly quickly, before I build a Sea Clipper 20. And yeah, I know there are maintenance concerns for the wood look, but the risk is worth the benefit for me. You know, the more I play with stretching the Drifter, it is starting to look just like a Sea Clipper 20!! I don't think the Sea Clipper is as light as the Drifter though. So, I think what I will do is like Dave said, stretch the length to give me a little more buoyancy, put some cedar wingnets on the akas, pin the akas so they pivot in for trailering like the Sea Clipper, keep the demountable function with some heavy duty wingnuts so I can cartop if I have to, and keep the pedals in the floor of the cock pit so I can sit down inside on a cold day to get out of the wind if I am sailing alone, but also add a tiller and extension for when I need to hike out in high winds. How is that for a crazy run on sentence? So I would end up with a longer hull, making it a little faster, and longer amas providing more buoyancy so I can step off a dock into the boat with out the ama(and me) sinking. That gives me displacement and seating for maybe 2 and half people. And, when I build a Sea Clipper 20, I will have enough seats for all the butts in the family if I take all my boats out at the same time. We could go marauding around the lake like a pirate fleet!

[Todd Bradshaw]

I'd need to know a lot more about the boat to venture a guess about how much sail area would work well. Even so, it would just be a gut feeling. I like to leave those questions to folks who are real boat designers, and they would likely also want to know a lot more about all three hulls before any conclusions could be drawn. On a tri, I think the design and volume of the amas is going to be a critical factor. Stuff or bury one and nothing good usually comes of it.

I really dislike jibs with unstayed masts. It's nearly impossible to get good and consistent jibsail shape when the jib luff's tension and subsequent draft are constantly changing due to changes in mainsail sheet tension. Bad jib shape usually contributes heavily to bad mainsail shape. It's difficult enough to figure out the right luff shape for a Bermuda mainsail on an unstayed mast that has some bend, but it is certainly possible, like on a Laser. Adding a jib with no wires supporting the mast really complicates the situation and lowers the chances that it will work well.

[Lee.007]

I really dislike jibs with unstayed masts......Adding a jib with no wires supporting the mast really complicates the situation and lowers the chances that it will work well.

So if you read on my "Newbie needs help" blog, I went out on New Years Day when we had some nice weather and heavy heavy winds. I tried a jib for the first time. I don't have any stays on my mast. I just ran a line from the mast head down to the bow. HORRIBLE experience. The jib shape looked like a balloon or a bad spinnaker. The interaction between the Main and the jib was not cool. Oh, and it didn't help that the winds were a steady 15 miles an hour, gusting to 20+mph. Yeah, I buried the amas a few times, and you are right, nothing good comes from a buried ama. Slows me down, kills my steering and sail setting for my course. If I am not thinking quickly and reacting, I can get capsized really quick. I ended up jumping in the lake and taking all that mess loose from the mast. I do plan on using stays on my next boat.

[Lee.007]

Oh, and for the next boat sail area guess, picture a drifter 16 stretched out to 19 feet, amas stretched out proportionately. I haven't figured up the ama dimensions yet. But they are 7 1/2" wide, I will probably increase the width a little when I stretch the length. I am thinking maybe 10" wide, and about 12 to 13 feet long, and set about 5 to 6 feet out from the center line of the main hull, 10 to 12 feet total beam. Any guesses for or suggestions for Sail area?