Boat Review: Didi 23
A sporty, good-looking, trailerable family-cruiser you can build yourself
Boat design is a study in the art of compromise. A vessel designed to be exceptionally fast, for example, might lack amenities like a comfortable cabin. Similarly, an especially seaworthy boat might not be all that practical for trailering. Many potential boat design virtues are, unfortunately, mutually antagonistic. When it comes to designing a sailboat there is—as they say—no such thing as a free lunch.
A typical boat design goes through a series of iterations beginning with the broad intended use, with each subsequent iteration addressing finer points and technical details—things like the rig, the materials and scantlings, and performance and stability projections. If the intended use is specific and singular—a one-design racing dinghy for example—one could argue it’s easier on the designer, who doesn’t have to consider many potential disparate design goals. In the case of the Didi 23, designer Dudley Dix had to walk the tightrope required to draw a boat that offered good performance, but also seaworthiness and comfortable enough accommodations for a family to cruise aboard. If all of this wasn’t enough, it also had to be trailerable.
Fortunately, like many prolific designers, Dix had some existing successful boats from which to draw. In fact, the Didi 23 is essentially a smaller version of his popular Didi 26.
“I drew the 26 for a client purely to fit a new trailersailer box rule that was introduced in Australia. The rule disappeared in a few years due to lack of support, but the design became pretty popular. We have sold plans for nearly 170 of them, with boats on the water in 41 countries,” Dix says. “The Didi 23 came into being because a client wanted the same boat but reduced to 23-feet for easier trailing and to fit a smaller berth—no other considerations. It worked out quite well.”
The Didi 26 was itself a sort of little sister to another of Dix’s designs, his DiDi 38 plywood cruiser-racer. All three designs employ Dix’s “radius chine plywood boatbuilding” method, which uses layers of plywood strips (about a foot wide) to skin the chine of the boat. The variable radius is tight in the bow and expands through to Station 5, then is constant through to the stern. You can read more about the method here.
To his credit it wasn’t immediately obvious to us which virtues Dix weighted most heavily in designing this all-round boat. While the 23’s long waterline and modern, wide transom suggests speed potential, the cabin is also fairly voluminous with four berths and a galley—even an enclosed head. And the self-righting stability of an 838-pound lifting keel and an open transom suggest she’d be up for whatever you might put a trailersailer through.
“I think the overall concept of this boat is good,” Dix told us, “combining performance to satisfy Dad for club racing, with enough comfort to allow a small family to weekend afloat. And the lifting keel allows them to get into sheltered or private spots when needed.”
We were excited to have a closer look at owner Casey Wilkinson’s Didi 23. We ended up taking her for a 30-mile spin from Bainbridge Island to Port Ludlow on Washington’s Puget Sound.
PERFORMANCE
“It points pretty well. I have had the boat up to almost 8 knots on a reach. I have heard from another Didi 23 owner that he has been up to 14 knots on a downwind run with an asymmetric spinnaker.” Casey Wilkinson, 2022 Koru
“Points great. Steers beautifully.” Steve Watson, 2014 Swell Rider
We left the slip under the quiet buzz of Casey’s electric motor, an ePropulsion Pod Drive 1.0. So as not to sully the lines of the transom, he chose the pod over an outboard and ingeniously located it in a box below the cockpit footwell. His 5 kwh LiFeP4 battery bank provides about 5 hours of use at full throttle (1000 watts,) and 10 hours at 500 watts. At 750 watts, boat speed is about 3 to 3.5 knots, where full throttle pushes the boat to about 4 knots. Casey also carries a 1 kwh backup battery and a 2300-watt gas generator for recharging.
Once free of the marina we hoisted the main and unfurled the 100% headsail in what was perhaps 4 to 6 knots of wind. The 23 locked in nicely in the light air and the helm was plenty responsive. The lack of a Code Zero or other additional sail area meant we were leaving some speed on the table, but Casey uses the boat primarily for daysailing and cruising, and the simplicity of the current setup is appealing.
As we tacked our way out into the more exposed air of the shipping channel, the wind continued to build. Pointing ability would be described as good. She didn’t go to weather like a racing dinghy, but neither did she disappoint or struggle to get us where we aimed. Tacking in about 8-10 knots of breeze our Didi 23 started flirting with 6 knots of boat speed. When the wind built to perhaps 15 knots as we approached Point No Point, we decided to tuck a reef in the main, but other than reduced heeling, the 23 seemed unfazed and continued along at the same comfortable pace. We should note that Casey added a sugar scoop transom section to his 23, taking the length up to 24’8”—a relatively simple modification that Dix happily signed off on.
We learned from Casey that during his build he’d opted for the shorter so-called “cruising rig.” At the time, Casey had anticipated using the boat largely as a trailersailer, so the somewhat simpler rigging made sense. We asked Dix about this and he wrote: “I recommended to Casey he build with the tall rig, which only adds mast height and mainsail area, because he lives in a primarily light wind area. He felt more comfortable with the short rig. I prefer to have lots of sail area for the light stuff then reef down for stronger breeze than to feel under-powered when the wind goes light.”
We’re all for simplifying the mast-raising and rigging process when possible, but there’s also no doubt the short-rig combined with the high-volume hull leaves some performance potential untapped. While Dix specifically mentioned light-air, we were also sure a more powered-up rig with a gennaker or spinnaker could get her on plane off the wind in heavier air, providing some additional thrills. The so-called cruising rig has a sail area/ displacement ratio of 18.84, where the stock tall rig generates a 20.7 ratio. Both are actually modest “cruiser” type numbers. Compare to Dix’s 21-foot Didi Cruise Mini which has a SA/D of 29.5.
A few miles farther into our test sail we noticed the unmistakable cat-ketch rig and wishbone booms of a Presto 30 sharpie sailing just below us. We don’t need to tell you what happens when two sailboats are going the same direction, suffice to say we began to pay more attention to our sail trim and course. Although the Presto exudes performance, she’s really more of a cruiser too, but it was nonetheless satisfying to easily hold the longer boat off all the way to our destination, including stretches both on and off the wind.
TRAILERING AND LAUNCHING
“The boat can be trailered on a normal boat trailer. The draft with the keel up is about 18 inches. It takes about two hours to rig and un-rig the mast, boom, sails, and running rigging. The boat weighs about 2800 pounds on the trailer, so a heavy -duty truck is not necessary.” Casey Wilkinson, 2022 Koru
“Trailering is not great for me because the keel is frozen in the down position.” Steve Watson, 2014 Swell Rider
As we’ve noted many times previously, we see a big difference between an easily-rigged daysailer or weekender, and a heavier, more complex trailerable like the Didi 23. At something like 2500 to 2800 pounds, with an 8’1” beam, the 23 is certainly trailerable—but with the fractional rig’s two sets of swept spreaders, upper and lower side shrouds, a forestay, and running backstay, this isn’t a boat we’d willingly rig and de-rig for a daysail. Casey, who keeps his boat in a slip, seems to have come to the same conclusion. He mentioned wrestling the sizeable mast into position for raising, with the spreaders catching on various deck components. “It’s really a two or even three-person job,” he said.
One critical advantage of the 23’s being trailerable, though, is the ability to pull her from the water seasonally or for bottom paint and maintenance.
SEAWORTHINESS
“I currently live in Hood River, Oregon, and sail on the Columbia River, which has some of the highest wind and biggest swells. My modified Didi 23 (now a 25-footer) handles the conditions extremely well.” Steve Watson, 2014 Swell Rider
“The initial stability is enough for my non-sailing family to feel very comfortable even up to 20 knots of wind. I have had the boat in wind up to 25 knots and 4 foot swells. With two reefs in it was bouncy, but I didn’t feel worried. With an 850-pound keel bulb 5 feet 8 inches down below, the righting moment is pretty good.” Casey Wilkinson, 2022 Koru
On paper the 23’s fairly conservative rig, stout construction, and heavy lifting keel would suggest significant seaworthiness. So too does the open-transomed cockpit and substantial 13”-high bridge deck, which would likely shed any water that somehow washed aboard. The only cockpit lockers are above deck without access to the hull.
The rudder isn’t exactly “transom-mounted” on Casey’s boat, but the post is outboard the cockpit and accessible, so it doesn’t create a potentially worrisome thru-hull. The rudder is a balanced spade type with the shaft going up through custom carbon tubes to the tiller head. This allows the entire rudder (with a small section of the scoop) to swivel up for trailering. The lifting keel (18” draft with board up) means the boat can potentially seek shallower anchorages, and being able to reduce draft to this extent is also a potential safety advantage.
Casey’s particular boat had substantial lifelines running its length, stern rails, and a bow pulpit, though not much to hold on to when going forward on the fairly wide non-skid sidedecks. A nice anchor locker forward contained the ground tackle. All of the running rigging was led aft and easily accessible from the cockpit.
In terms of how she felt on the water—and to the extent we could gauge her seaworthiness over the course of a 30-mile sail—we were impressed. We mentioned tucking in a reef at one point, but even in the gustiest conditions we encountered, the 23’s helm never loaded-up and the boat never behaved erratically. In fact the decision to reef was made casually, and mostly because we noticed the boat was heeling somewhat more than would be ideal for performance—though prudent seamanship also suggested we anticipate the wind might continue to build. All in all the Didi was forgiving and well-mannered.
We told designer Dudley Dix we thought his 23 felt like a larger keel boat in the rougher swells. He responded: “A long waterline combined with a high prismatic coefficient and unbalanced ends (fine bow and broad stern) creates a boat that pitches little in head seas. This allows the rig and keel to maintain stable flow for much better speed than a boat that doesn’t have those characteristics. That reduced pitching also makes it feel like the motion of a bigger boat that would naturally pitch less than a small boat bobbing in the waves.”
The Didi 23 scores an impressive 188 points on our SCA Seaworthiness Test.
ACCOMMODATIONS
“For daysailing 6 people can comfortably fit into the large cockpit. For cruising, 4 people can sleep aboard for short trips. For longer trips 2 or 3 would be more comfortable. I added a sink but no plumbing, so portable water containers act as the faucet. The head is very practical. It is fully separate, and a person can use the head with the door closed with total privacy. This was one of the reasons I chose this design to build. There’s a ton of storage under the berths and in the galley cabinets.” Casey Wilkinson, 2022 Koru
The Didi is just big enough to offer one sought-after cruising amenity rarely found on trailerables—an enclosed head. The head and the highest belowdecks areas offer only 4’2” of crouching headroom, but there’s also a spot with “standing headroom”— directly under the spring-loaded companionway hatch in the open position.
There’s a nav/electronics station to starboard immediately inside the companionway, and a galley unit to port opposite the head. Under the cockpit are a pair of 6’6” x 24” quarterberths, and all the way forward is a 6’9” by 5’9” V-berth—all with stowage beneath. Casey also installed tinted rectangular windows just below the sheer, above the quarter and V berths—a great idea that affords more light and gives the boat an expensive look.
QUALITY
“Since I built it, I think the construction is top notch! As long as the boat is built according to the design, it should result in a very sturdy, light boat.” Casey Wilkinson, 2022 Koru
With owner-built wooden boats we obviously have less to say about quality than we would with a production boat. We look at scantlings, the designer’s suggested materials and methods, we examine the boat we’re aboard, and we ask owners about any perceived or noted shortcomings. On all of these points the Didi 23 scores high marks. Furthermore, it inspires some confidence to build a boat drawn by an especially experienced designer and sailor like Dudley Dix.
COMPROMISES
“With the swept back spreaders it makes the mast more difficult to raise and lower. I originally thought I would keep the boat on the trailer, but decided I would get much more use out of it if I kept it in a slip due to the time it takes to rig.” Casey Wilkinson, 2022 Koru
We’ve touched on what we see as the primary compromises already. The 23 is a good performer and comfortable cruiser, but not extraordinary in either of those categories. Obviously some boats will be better for either purpose if bigger tradeoffs are made.
While she’s referred to as a “trailersailer,” we expect most owners won’t regularly trailer-launch for the weekend, but will instead keep her in the water for extended periods.
MODIFICATIONS
“I extended the transom from 23' to 25’. I also designed and installed a balanced rudder. Not difficult and definitely successful.” Steve Watson, 2014 Swell Rider
“I made several modifications. I added an anchor locker in the bow, changed the companionway opening from vertical to slightly angled, and added a sugar scoop to the transom with extended the LOA by about 20 inches. The most significant modification I made was adding a retractable electric pod drive as the auxiliary propulsion.” Casey Wilkinson, 2022 Koru
The two builders we interviewed made many of the same modifications, suggesting future builders might consider them as well. While both builders opted for what are effectively inboard rudders and sugar scoop sterns, Dix’s standard plans provide for both a transom-hung and lifting transom-hung rudder with balanced at a ratio he says has proven to work best.
We asked Dix if, with the benefit of hindsight, he would change anything about the design. “If designing the Didi 23 and Didi 26 from scratch, I would have used 3-4” more freeboard but that was a given for a competitive boat in the box rule I was working with for the Didi 26. That said, the proportions of the 23 turned out rather nice with that freeboard, whereas the 26 looks a bit too low.”
VALUE
“I think to have one built would be similar in price to a new Beneteau or J boat of the same size. If you built it yourself, the cost would likely be less.” Casey Wilkinson, 2022 Koru
“Building took me a year; the quality of the plans was excellent. As this was self-built, I can say that construction is rock solid; rigging came from a Farr quarter ton rig; absolutely no shortcomings or corner-cutting in the design.” Steve Watson, 2014 Swell Rider
With probably only a few ever built (16 plan sets sold), it’s unlikely you’ll stumble upon a Didi 23 on the used market. The advantages and disadvantages of building your own boat are mostly self-evident—but if, and only if, you enjoy the process and labor involved in building a boat, then it’s a great way to go. Dix offers complete plans and full-size mylar patterns to speed up the process.
If you’re considering building a boat in this size range, and looking for a design that strikes an especially good balance between performance, comfort, and seaworthiness—and you want to be able to trailer it—the 23 should be high on your shortlist.
We really enjoyed our sail on the Didi. In a variety of conditions we negotiated traffic and currents, reefed and shook it out, ate lunch underway—even engaged in an informal race with the Presto 30. Throughout it all the boat was comfortable, responsive, and fun to sail. One of our crew probably said it best: “There should be more boats like this on the water.” •SCA•
For more information on this or other Dudley Dix designs click here.
Review boat builder Casey Wilkinson is a for-hire professional builder. You can visit his website here.
I like what I'm seeing - not that I'm in that market...
I think Webb Chiles has got one more circumnavigation in him - looks like more comfort than he can stand?! Webb can give it the test that will tell all!