Krogen 50′ Open: Progress Report #2

Wow! What a difference one month makes. I reported in December that the hull lamination was barely complete—and now, hull number one of the Krogen 50’ Open series is out of the mold. As you can see, she is all Krogen. A fine entry, a long, full keel, and her beautiful wineglass stern.

Now that I’ve clicked through (at least a few dozen times) the most recent set of photos that Tom sent to me and Janet, I thought I would point out a few of the more notable facets that are depicted.

1. The stem, bow (or whatever you want to call the pointy end!): The Krogen 50’ Open, like all Kadey-Krogens, has what naval architects call a “fine entry”. There is relatively less of the forward portion of the boat in contact with the water than a blunt entry like that found on many other trawlers. This means she will be knife-like (relatively speaking) as she moves through the water. Picture moving a butter knife though a stick of butter that is at room temperature. The knife will move through the butter with relative ease. Now think about trying the same task with a chopstick. The chopstick will get through it, but will require more force than the butter knife. More force equates to more power which equates to greater fuel consumption. The fine entry of a Kadey-Krogen results in lower fuel consumption than other comparably sized vessels.

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There is another benefit to the fine entry – the motion of the boat in a head sea. Every boat pitches in a head sea. Period. One difference in the ride between a good boat and a great boat is how the pitching motion feels to those aboard. I’ll use another analogy to describe the motion afforded by the fine entry. Pretend you are standing at the side of a swimming pool facing the water. Now turn your body 90 degrees to the water and fall into the water on your side. You hit the water with little pain and little resistance – the fine entry. Now pretend you are standing at the side of the same pool but do not turn your body. Fall straight forward into the water. You hit the water – smack, and you feel your body shudder. That’s representative of a vessel with a bow that has a more blunt shape.

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2. The stern: The second photo is a terrific representation of the wine glass shaped stern of the Krogen 50’ Open (and a characteristic of all Kadey-Krogens). This shape provides three major benefits when underway. First, it helps to reduce pitching motion in a head sea. When the bow of a vessel raises up the stern naturally goes down but at the same time the stern tries to resist and force the bow back down. The wineglass stern is not parallel to the water, so much of the wave energy is deflected away and the bow is not forced down as hard as a boat with a flatter stern. Since the bow of the Krogen is not forced down as hard, the pitching feels more gentle.

The second benefit is readily observed in a following sea. Most powerboats are difficult to steer in a following sea and I know many of you reading this can attest to that statement. A very accomplished captain once told me that “head seas may be uncomfortable but it’s the following sea that can kill you.” Jim Krogen, being a recreational boater himself as well as an accomplished naval architect had that in mind when he designed the hull form that we still use today. Because of the wineglass shape at the stern and its associated soft chines (where the bottom of the boat meets the sides), there is little of the back end of the boat in the water. When a Krogen is in a following sea, the wave lifts the boat and passes underneath without a huge change in direction. Powerboats that are flatter at the stern and have harder chines tend to get pushed around by the following sea. In addition, when these boats start to come down the face of a wave, they will veer off to either port or starboard because the hard chine tends to dig in and steer the boat much like a water ski or snow ski will turn when pressure is put on an edge. The Krogen tracks straight and true without a lot of fuss.

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3. The core material (used only above the waterline) has been vacuum-bagged in place. Using coring material which is vacuum bagged in place allows us to reduce weight without compromising strength. The core also has the benefit of provide insulation to the living spaces. In the photo to the right, you can see the dark line where the solid hull transitions to the cored portion.

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4. You may also notice the cutouts where the watertight doors will be in the engine room, and where the fuel tanks will be placed. If you look closely, you can see that the bulkheads are have been coated in resin, an extra step we take to help ensure the integrity of the bulkheads.

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But perhaps what is most evident (if you use a touch of imagination), is the height in the engine room. The dark brown cross member sits just aft of where the transmission will be, and that area is six feet off the floor. Headroom at the front of the engine approaches seven feet! Tall people have always loved the roominess of a Kadey-Krogen, but this takes it to new heights (pun intended)!

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And, what did Janet and I do over the last month? We made decisions! We chose the sinks and faucets for the master head (yes, plural…as there are two sinks in the head of the midship master layout) as well for as the guest head. We also spent a lot of time discussing countertop material for the galley. Corian, granite, Silestone, Cambria, Caesarstone…and the list seems to go on and on. For us, the decision was made based on personal experience. When we remodeled our kitchen nine years ago, we installed granite countertops and have liked the way they have stood the test of time, so granite it will be in the galley. Weight is not that important in a full displacement trawler, so we are not bothered by the few hundred pound-difference between granite and a quartz material. We are still deciding on the counters in the heads, but we are leaning to a quartz material since we think we would like a more solid coloring on those surfaces.

Navigational electronics are almost set and we are going 100 percent with Garmin with a laptop and portable GPS as backup (in addition to paper charts). Understand that this is my personal preference and it does not mean that Garmin is better than the other manufacturers of marine electronics. I just like the Garmin user interface better than Furuno, but on the other hand, in greater than 60 percent of our new builds, the customers are choosing Furuno. As Tom says, “that’s why they make chocolate and vanilla ice cream.”

The pilothouse will have two MFDs (multi-function devices), a dedicated depth sounder display, two VHF radios, autopilot, and a USB output from the network. The MFDs will run the radar, the chart plotter, sounder, and four cameras. We are still working on the details, but I think there will be two cameras in the engine room – one facing aft towards the alternator and serpentine belt and one facing the transmission and dripless shaft seal if they can both be shown. These cameras will not be a substitute for engine room checks but will allow me to monitor key components of the engine and drive train while as desired. The other two cameras will be outside and face aft. One at the swim platform and one aimed straight back so in close quarters we can easily see any boats behind us.

The flybridge will have a single MFD with remote microphones for the two VHFs, a dedicated depth sounder display, and an autopilot control head. Lastly, the two wing stations will each have an autopilot control head, so I can control the rudder during close-quarter maneuvering. Some electronics manufacturers allow you to interface with a jog lever to control the rudder from a wing station, however Garmin does not allow this interface—hence the autopilot control head.

Why do I need to control the rudder from the wing station? Two reasons – redundancy and maneuverability. We have chosen to have a hydraulic bow and stern thruster which in theory (and most times practically) will let you spin the boat within its length and make moving sideways off a dock by simply pressing both levers to the side. However, we have had many experiences where the wind or current made it quite challenging to move sideways from a dock, even with bow and stern thrusters. This is because the movement of the stern in a sideways manner must fight the large keel in addition to wind or current. If we are tied starboard side to a dock and I can control the rudder and turn it hard to starboard, I can then use a short burst of forward power to kick the stern away from the dock while still using both thrusters to help.

That about wraps it up for month two. I hope you enjoy the annotated “sonograms” I’ve included with this update. Next month we should have photos with machinery in place as well as photos of the superstructure and flybridge.

Until then, fair winds and following seas.

-larry

p.s. A great animation of both a with a wineglass stern and one that is flatter in the aft sections can be seen in this short video.

Did you miss Progress Report #1?  You can read it here.

To read Progress Report #3 click here.

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