At the end of 2018 I posted a power cat hull build. Upon completion of the two hulls, they were picked up by the owners and taken home to Maine to build the crossbeams and cockpit, as well as fit engines, electrical, etc. I’m happy to report that the resulting boat looks spectacular, and the owner/builders say that the shakedown cruise went well, with a smooth dry 20 knots. stock props.
I found a picture of the new Lake Chelan ferry taken during sea trials.
It was loaded down with about 8000 lbs. of sandbags, which was to simulate 32 passengers and a ton of cargo. It did the required 20 knots, but I thought it should have been able to do better. It still could.
The pair of 200 hp. outboards were still new and weren’t pushed exceed 4000 rpm. The props had not been experimented with.
There was substantial water sloshing around in the bilges. The roll and tip bottom paint application was never tipped. The surface was like sandpaper. The owner can wet-sand the hulls. And finally, there were a few divots below the waterline that could be filled next haul-out.
I took on the job of building a set of hulls for Kurts 28’ power cat design which we stretched to 31’ by adding about 2.5 inches to every station. We upped the stringer size by 30% and glassed with 8oz rather than 6oz but otherwise stuck with the plan and laminate schedule. We used multiple layers of 8 and 10oz to make up biax tapes, i find it makes for easier fairing and allows for tapering the buildup. We did a half-way-to-yacht quality fairing job, primed with 545 and installed cleats, hatches, fuel tanks, and fuel fills. There will be lightweight 25 hp engines mounted on rear transoms. We finished both hulls and shipped to the owner in maine, who is going to build the cross arms and center cockpit over the winter. I really can’t recommend committing to building a boat over the summer in sarasota, florida in a non-airconditioned space, but, in the spirit of running a marathon, and other ridiculously painful ways to enjoy yourself, we did it. Total build time, including purchasing, hardware, and mounting on a trailer for shipment, was in the neighborhood of a thousand hours. LOTS of pictures after the break-
The MV Bluebird is undergoing seat trials on Lake Victoria now. It is built from developed plywood/epoxy, with lots of core on flat surfaces. The whole thing went over in several containers after it was built near Seattle. I will be offering an option that is not quite as wide and a little lighter also.
This office has been a leader in creating efficient, user friendly passenger ferries.
Most of the catamaran ferries that I see are designed by large design offices, and in my opinion, designed badly.They are usually metal, are heavy, have poor efficiency, and a poor ride, compared to what they could have.There are significant reasons for that.Those catamaran ferries come from offices who have been designing single hull ferries decades. They do cats now like they always did the monos.
I come from a sailing catamaran background. Instead of just piling on the horsepower, efficiency is important. I carry these lessons to the passenger cats that I design. I expect the gold plate design offices will figure this out in 5 years or so. That technology here now. For more discussion ofdisplacement power multihulls see this article.
We offer a full line of USCG-certified multihulls and the experience in working with the Coast Guard to get owners operating in the least possible time.
KHSD Charter multihulls emphasize functional, efficient design combined with longevity and durability. Many of these designs can use rapid construction technologies for hulls and house cabins.