Montage
I’ve drawn a lot of small trimarans in the last seven years, beginning with my A18 for performance coastal cruising. During that time period, there has been an explosion of other small, daysailing trimarans on the market, most of them coming out of France. Recently, a new trimaran/skiff hybrid has been introduced from New Zealand called the Weta. www.wetamarine.comThis boat has immediate appeal to beginning and intermediate sailors. It offers much of the speed experience of a high performance skiff in a stable and predictable platform that is really tough to capsize. The Weta is one of the first boats to encourage family participation and reintroduces the waterborne fun of the beach sailing culture, established way back in the late 60’s with the intro of the Hobie catamaran.
A brand new, factory built Weta goes out the door for USD $11K. Realistically speaking, this isn’t an in surmountable amount of money for a factory produced, brand new carbon trimaran. It is, however, quite a lot of money for most casual recreational enthusiasts and the folks who like to build their own boats… especially when you consider the rugged economic conditions we all face these days.
So, I decided to take a whack at producing a set of plans for a homebuilder’s version of a Weta-like hybrid 
that could be buildable in the neighborhood of $5600 ready to sail with a new mast, sails and trailer. I’m calling the new boat Montage, as it is an assemblage of concepts that fill the slot between a performance skiff and a small, quick trimaran. This boat will appeal to sailing enthusiasts from kids to codgers who just want to get out on the water and have a fun and fast experience without breaking the bank.
The estimated $5600 figure represents a boat with a whole host of brand new parts. For the clever builders out there, the Montage could be even less expensive if they can find a used 470 rig, perhaps a used small craft, or beach cat trailer that could be modified to fit the hull design and even a collection of hardware in good condition. The Montage is a very light boat at right around 235 lbs., so you do not need to buy a heavy duty trailer.
After a dozen different sketches of boats that fit the general design motif, I settled on a plywood multichine hull design that had virtually the same dimensions 
as the manufactured version. When I projected the hull panels to a two dimensional layout, though, I saw that I was going to be wasting a good bit of plywood by going with a 14′ 5″ boat that mimicked the dimensions of the production version.
I went back to the drawing table and reconfigured everything so that the longest hull panel was going to just fit on a couple of sheets of marine ply laid end to end. The main hull also got just a bit wider in the process of lengthening the boat. Where the factory boat uses carbon fiber on foam cores for its structure, the Montage will be a 4mm marine plywood design with full fiberglass/epoxy sandwich laminates inside and out. The foredeck and the cockpit seating transitions are strip-built in Red Cedar to give the overall appearance of the boat a smoother, more organic feel than straight plywood panels.
The amas for Montage came from a 16′ trimaran design that I had already done and required minimal re-design to work with this boat. The amas are also designed as multichine ply forms with pretty high volume shapes well forward and a water shedding deck form that will helps to keep them riding high even when driven hard. Ama displacement is 100% of the all-up boat weight when sailing.
Montage Specifications
LOA 15′ 6″
BOA 12′
BOA main hull 41″
Main 110 sq. ft.
Jib 38 sq. ft.
Screacher 102 sq. ft.
Displacement 650 lbs.
Weight 235 lbs.
The aka beams are anodized aluminum instead of carbon tubing. The inboard ends fit into fairly burly sockets in the hull and are held in place with quick release pins. Flat deck flanges on the ama ends are welded in place and bolted to the amas. The amas are removable from the aka tubes for repair or maintenance, but otherwise stay mounted, along with the trampolines, as complete units.
The mast is also anodized aluminum. The boat uses the same mast section as the 470 dinghy, which is a Proctor Cumulus section. This mast is available on the used market with a little bit of hunting around. If you want it all and have the money, then there’s a very cool, filament wound Forte carbon spar available with very close specs to the Proctor that will rock your world. http://fortecarbon.com/
Making these two changes from the benchmark, all-carbon Weta to an aluminum spar and tubing keep the costs down, with but a slight weight penalty over all-carbon parts. If you find a used mast, the savings will be even more substantial.
The mainsail and the jib will be built in Dacron instead of a more expensive fiber/Mylar laminate sail. The jib is a self-tacking blade. The main is a boomless design, which will keep head bonking incidents out of the picture while sailing. The screacher is furled from the bowsprit for simple convenience.
I have found that the more expensive sailcloth laminates are capable of driving the boat just a bit faster, but for the average recreational sailor, they will hardly ever make a difference compared to more forgiving sails in Dacron. Dacron is much easier to maintain, lasts longer, is a lot more tolerant of UV exposure and can be repaired by any sail loft wherever you go. If the builder of the Montage really wanted to, they could buy a set of sails in something like Pentex laminate instead and they’d have that hot, performance boat look that some desire along with just a bit more zip under sail.
The overall design of the foils and their operation is pointed directly at the needs of a recreational sailor. The boat uses a centerboard for ease of use 
and pretty much no-brainer beaching. Likewise, the rudder is a flip-up style unit that eliminates the problems of hitting underwater objects. The foils will be built with template shaped cedar cores having a white ash stringer for stiffness and then glassed for durability.
The aluminum aka tubes will be sold pre-bent and ready to install on the amas. If the builder has access to a good mandrel bending facility that can handle the OD/ID specifications of the tubing, they can fabricate their own tubes to supplied specs.
The Montage is designed to be a really fun day sailing machine that can generate near performance skiff sailing speeds while offering a hugely stable platform for recreational sailing. Construction of the boat is very straightforward in marine plywood with glass/epoxy laminates and can be easily built by any sailing enthusiast who has household handyman skills with tools. The Montage has been created to offer homebuilders an opportunity to enjoy this style of family sport boat at a completed cost that is far less expensive than the manufactured version.
Chris Ostlind
Lunada Design
Posted: February 21st, 2009 under Sailing Multihulls, Trimarans.
Comments: 11
Comments
Comment from Ric Allen
Time: February 22, 2009, 9:08 pm
Hi Chris,
I am greatly interested in this project for all the reasons you have outlined. Do you have a price for plans yet ?…. I agree the Weta is a great design but the lack of do it yourself goes against it.
Something I have considered ( and please let me know your thoughts ) is to convert a 14′ dinghy to a small trimaran. I recently sold my NS14 ( http://www.ns14.org ) which was 10 + years old. These are great boats and quickly get overpowered with a light crew, so fitting amas gives this style of boat a new dimension. There are plenty of ’superceeded’ models which can be bought cheaply fully rigged on trailers for AUD$2500 ( new ones are $15,000 ) so if the home builder was to spend time and money on amas this is a way of re-birthing a great boat and keeping people on the water
Ric Allen.
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Hi Ric,
Yes, I think there is some real potential in retro-fitting an NS14 to a Montage-like arrangement. Your comment about older boats getting this kind of treatment is terrific. If you can do this and keep the weight down on the retro work, then you could still have a decently performing boat.
You would be at a small sail area disadvantage compared to a Weta, or Montage, but careful building and a pair of lightweight amas could possibly get you close to their SA/D figures. I’d also suggest a furled chute of some type for offwind work.
ChrisO
Comment from john colley
Time: February 23, 2009, 1:41 am
I love the design and concept. I have a 17footer pirogue which will be fitted with substantial outriggers and mast too. For just the same reason you have said, fun and carefree sailing. Look foreward to seeing the plans.
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Thanks, John.
I’d like to see your pirogue project as you move along your design/build path. It sounds interesting and you just may end-up a total small trimaran nut, if you’re not careful.
ChrisO
Comment from Roger Dann
Time: February 23, 2009, 6:49 am
Hi Chris,
we are always looking for new ideas. We are a small startup company selling 8m catamarans at present but I’m looking for a small simple beach tri to produce in China and market around the world. Interested?
Regards,
Roger Dann
Comment from Dan
Time: February 23, 2009, 7:36 am
Looks great!
Dan
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Thanks, Dan
Chris
Comment from Manfred Pech
Time: February 24, 2009, 6:34 am
Hi Chris,
I tried to compare the lines of Wetas main hull with yours and (as far as this is possible) found out, that Montage is the more consequent skiff hull than Weta. This in my opinion will offer sooner and better planing, but I can not amagine the drawbacks of this solution for a Trimaran.
The most interesting I have read about Skiff hulls was from Frank Bethwaite (High Performance Sailing) comparing different hulls (Chapter 20: Hulls, P.247 ff) and the “Intership Report, 49er performance enhancement”, May-July 2007, P. 6ff, describing tests and the following refinements of the 49er hull. Especially the positive effect of chines has been tested and discussed.
As a result the chines have been sharpened and the after section has been sanded to be perfectly plane. This is a strong vote for a plane plywood bottom (P.16) and will help to get a better water flow separation when the boat is planing (froude 1.2 plus) (Page 17).
From this point I think the chines of Montage are very important and more effective as on Weta and I am interested to hear, how this combination with the floats will work.
I do not know if you have heard of John S. Taylor (Aus), who designed and built a 20ft Trimaran with planing main and planing floats. This Trimaran is said to have been clocked 309 NM per 24 hours.
Do you think it is usefull to design planing floats too ?
Regards, Manfred
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Thanks for your interesting comments, Manfred. I’m flattered that you have taken the time to look at the design with such a technical eye.
You are right, I was looking to get the main hull of the Montage up on plane early, so that the owner/builder could get a solid return on his effort and expense.
I also agree that there is a beneficial result from the chined hull sections with regards to separation. I looked at a lot of power boat hulls while I was tinkering with the design and saw real advantages in that direction.
As for planing floats to produce a fully planing trimaran… I do see the potential in that direction, but there is a price to pay at slow speed. I find that, for a recreational boat, the use of slender amas is more beneficial for good all around sailing. This means that the average sailor driving the Montage will be able to enjoy the performance potential over a wider range of wind and boat speeds. If a person lived in a location where consistent strong winds were present, then it could be a real blast to have a fully planing version of this boat as a daysailor.
Chris
Comment from Gerhard
Time: March 3, 2009, 10:17 am
I think that the Montage would be a terrific boata here in Brazil. What is the cost of the plans?
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Gerhard,
The plans will be USD$125 when completed. I would estimate that they will be ready in the next three weeks (end of March)
I will send you a notice via email as soon as they are ready.
Chris Ostlind
Comment from Emanuel
Time: April 5, 2009, 6:25 am
I am greatly interested in this project for all the reasons you have outlined. Do you have a price for plans yet ?
i am writing from Brazil!
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Hi Emanuel,
Thanks for the fine words. The plan package will run USD$150
The Montage should be a terrific boat for hundreds of sailing locations in Brazil.
Chris
Comment from Eric Jones
Time: July 3, 2009, 2:41 am
This is a great design, largely due to the fact that it realizes the use of the outer hulls as a second set of blades. It’s fairly easy to see in the last picture. As it heels to leward, it’s going to put the leward hull straight down in the water, and go up on the corner of the main hull. It’s brilliant, but there are two things that need addressing.
I sail in the San Francisco Bay in California usually racing CFJs, and the first thing that hits me looking at this, is that if one person is sailing it with one more person in it, the skipper may want to be hiked all the way out, harness included. It may be a good idea to continue the tarp around the outside of the outer hulls from where it ends now. If that becomes the case, you may want to make a rudder bar with three points: one in the cockpit and one on each wing. You could even do something stylized with that, like putting them on light springs to keep them out of the way. My main point is that in heavy wind, this boat will most likely start to shake.
Another idea, just to make things easier for the skipper, would be to not only split the main and jib sheets so that they would end in the cockpit and both wings, but to put the aft jib on a car, so that the ship could potentially be single-handed.
A somewhat smaller, but more annoying alternative to splitting the sheets would be to make a third hand device for one’s belt. That would solve the same problem, but weigh the sailor down dangerously.
Comment from Mike
Time: July 14, 2009, 11:09 am
Chris,
I recently purchased a Windrider 16. It truly is a solo craft, seating on the trampolines is very wet, and uncomfortable. I have a wife and 2 kids I want to do the family sailing with. I have not sailed a Windrider 17 yet, but I am leaning on that being the replacement. Your design here is very interesting. How many hours could an average DIY expect to invest in this project? Is there any requirement for special equipment?
Thanks.
Comment from Peter
Time: November 2, 2009, 5:52 am
Chris, what a great idea. If the plans are finished I’d love to buy a set.
Regards Pete
Comment from Peter Erik Fuchs
Time: January 2, 2010, 4:06 am
Hi Chris: I have great respect for what Roger and Chris Kitchen have achieved with the WETA and I have been fortunate to sail one of the 2 first boats to arrive here in Japan. The y have done a remarkably good job of fine-tuning the design around what matters, ease of use, modern mast and sail design etc. Yet the cost factor! I have bought a hull license for the i550 from Watershed to have the fun/challenge of building a sportboat locally here in Japan. That said, I would also be happy to pay you for the completed plans (and if possible full-size Tyvek or other plastic layout material. Responsibly forested plywood is remarkably cheap now in Japan, and I would love to get started on the Montage ahead of the monohull i550. We have lots of hardly used 470s in Japan, as the sport is suffering a lack of participation, but many colleges own boats without sailors. Please let me know when you can have the metric version of the plans for the Montage ready to ship – hopefully with practical hints, esp. regarding alum. proa tube shapes. All the best Peter in Tokyo
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