I don't get it, this is such a simple hull shape, originally made in plywood, that works as well as most molded hulls. I'd put it in a list of top five "all around" sea kayaks with this one giving more speed and stability than most.
The 16'x21", 17'x22" and 18'x21 Mergansers are similar in pivot point resistance to weathercocking and response on a lean, the 17W sticks out regarding weathercocking and response to a lean. You could toss five lbs in the stern or add a long 3/4" skeg to the stern but a retractable skeg would probably be ideal. Moving the seat back would put one up against the coaming. What would really be ideal is a slight re-design so it handled similar to the other Mergansers.
A couple things are worth mentioning for the next builder. The coaming has little overhang on the sides so trimming the two halves of the coaming spacer might help make a little more overhang on the sides, maybe a shade under 1/8" would do it. I've got about 1/2" overhang which feels minimal. Pre-glassing the inside of the hull panels before stitching up makes finishing the interior easy. The thigh braces on the coaming recess are mounted kind of far forward and inward, I've trimmed the inside and forward portion of the thigh braces to allow more room for entry/exit but they need to be moved back about an inch. On the next one I'll connect a little piece to extend the thigh braces closer to the thighs instead of knees.
Ok, handling, think of a slightly tippier Caribou with stiffer tracking but less weather cocking. It'll have less of a tendency to slide sideways on a wave compared to a Caribou but it'll still turn where you want with a constant lean. It won't allow as much green water over the foredeck as a Caribou. I only had a chance to take it out in 15mph breeze but it felt good in all angles to the wind/waves.
The 18 is not a big kayak, I think it's about a half cubic foot bigger than the Caribou, but for 200lb paddler with 60lbs of gear I bet it would be great in a lot of wind. For reference I've built two Pygmys, seven CLCs, a Merganser 16 and my own attempt at a 18'x21" s&g kayak. Have worked in kayak stores and taught sea kayaking.
Two thumbs up.
The few times I got onto small surfing waves it was surprising to find it 'settled down' while flying. Most kayaks get kind of 'busy' when the transition to high speed happens on a wave but this one gets 'settled'. The bow develops lift at surfing speeds that you don't discover until moving fast down a wave. "Hmmm,,this was meant to be this way". Hopefully it'll be as satisfying in the ocean as the Chatham16 turned out to be.
The beam measurement doesn't mean much,,it's more stable than you'd think a 20" wide kayak would be. Certainly more comfortable than an Elaho HV.
One aspect that I'm sure is a marketing decision is that the cockpit is big,,the foredeck could be an inch lower. I'm 5'9" with size 11 feet and have a extra inch of foot room with feet oriented straight up,,which makes me think it'll fit folks 6'4" with size 14 feet just fine if they're accustomed to narrow kayaks. I'm happy for you 6'4" paddlers with size 14ft but you're outside the bell curve,,Necky? bring out a lower foredeck boat with a smidge less aft deck por favor. As it is I'm rigging the underside of the foredeck with LOTS of bungie for misc. gear.
Details,,the construction technique is fairly unique, it looks to involve less labor in deck/hull assembly than the average deck/hull construction that uses interior glass tape, it uses an adhesive with no interior/exterior seam tape. It's got a very low resin/glass ratio which would imply a higher strength/weight ratio. I wasn't aware that the interior glass deck/hull flange was a guide and not a structural bonding element so don't worry if it looks like there isn't adhesive between the flange and the hull,,the adhesive is on the exterior flange. I figure if you got something in there it might as well be bonded but the folks at Necky say it's fine. So I'm going to take them at their word and USE it well.
You'll get a kick out of the construction,,shine a flashlight in the compartments and run your hands around the inside,,,different, I'm charmed with it. Messing with kayak building can do that to a person.
Unfortunately you can't get one shipped with the forward bulkhead uninstalled for custom placement but that was fortuitous in my case. I had it shipped without footbraces installed and was considering cutting out the bulkhead then re-installing one further aft with interior mounted Yakimas as there's a LOT of unused volume in the cockpit. In the mean time I've stuffed three big blocks of 3" minicell for footbraces. All these years I've put up with footbraces,,no more,,I might eventually reposition the bulkhead but in the mean time it's nice having a larger footbrace area than just the ball of the feet,,much better.
The glassing around the aft end of skeg box needs to be re-figured as there is one exterior 5" gel coat crack in the hull that came as delivered, I suspect the skeg box provides a rigid point from the flexible hull panel but it doesn't look like a structural issue regarding the hull itself,,more that the gel coat can't bridge the transition. For folks unfamiliar with gel coat it'll be disconcerting,,and most folks spending $3000 will probably make the dealer fix it or send it back but I'm doing so much stuff to it that it's minor. In heavy use your average glass kayak gets stress cracks in the gel coat,,something tells me this kind of construction won't get as many.
When the Perception Sea Lion came out years ago it was THE boat you'd get if you were a beginner who wanted to learn with the bar set a bit higher than a beginners comfort level. The Chatham 18 is kind of like that but with a higher bar for the average customer now that the average customer should know how to brace/roll. Kind of like when an athlete decides to get into cycling and jumps straight to a road bike with skinny hard tires after riding mtn. bike with larger tires and shocks. The Chatham18 has show room leg comfort, predictable handling on the water, it'll force a beginner to learn how to brace and lean but not be so far out there to eliminate the experienced paddler who likes some stability.
There isn't an appreciable weight/cost difference between the glass and carbon/glass version so Necky should market the attraction of the carbon/glass composite better.
More misc. thoughts,,the ratchet back band adjustments are ridiculous,,all that work to make recessed hardware in the coaming to accomodate them,,toss them out. Who adjusts a backband while paddling a 20" wide kayak??? That's like needing tennis shoes that can be retied while running. Makes no sense.
I haven't bought a new composite kayak in 12 yrs and this is worth it so far. I've owned a dozen kayaks, teach sea kayaking.
Positives: The Chatham16 is excellent for handling in high winds, mild weathercocking that skill or skeg can counteract. Similar to my Express in control but without any of the tendency to slide sideways across the surface of the water. This is the boat to have if you're stuck in high winds. Stable. Good combination of maneuverability and tracking. There are more maneuverable kayaks, there are stiffer tracking kayaks.
The cockpit is accomodating to modification but I don't think it's what Necky intended. Toss the blue minicell seat and carve your own. I've been in small surf a few times and like it. The coaming is narrow enough that with the aluminum thigh braces removed I can have adequate bracing for rolling but can paddle knees up when I want in flatter water.
Negatives: Aluminum seat frame is the wrong size to accomodate more paddlers who can fit the displacement of the hull. I've got a 31" inseam and HAD to shove the seat frame all the way to the aft setting so as to not experience cutting pain from the frame. With the new carved seat from 3" minicell, chunks of foam extending forward from the frame it's perfect. The rusting ratchet seat back widgets are worthless, throw them out. The aluminum thigh braces are ok but find the narrow coaming provides adequate control for rolling/bracing in surf. Maybe there's an old fashioned set of braces I can cut to fit. There needs to be a different hatch gasket material, redid the day hatch with 1/16" neoprene and that fixed it. The other hatches are next as they take on at least a pint in half a days worth of surf.
This is a good kayak, fixed mine with under deck bag, doubled deck bungies. Found a soccer ball on the river today, jammed it under the two doubled foredeck bungies and it made a great bass guitar. Good tone. I have a composite Chatham18 on order.