I'm now leaning towards a standard Tolman Skiff but maybe with his Seabright modification.
The big issue now is if I can afford, in terms of power and performance, to put the wheel house or small cabin so I can stay out of the rain. We'll see.
Hi Ken, welcome to the new forum. Great post! very informative. I've been watching the progress of the seabright attentively and it's great that one has actually been built in the Philippines (hull #2 at that).
You are now the record holder on this forum for the longest post. 1,717 words!.
Looking forward to more of your posts, please post more pics of the seabright as soon as you have it.
A buddy of mine is also looking for an offshore fisher and he's looking at the Tolman Jumbo. Once he sees your inboard seabright I'm sure he'll change his mind.
Building the Tolman/Seabright skiff
What the world needs is a truly economical planing-hull power boat. Sure, Tolman skiffs are economical compared to other boats in their class due to their relative light weight, but the sad fact is an 18-wheeler running down the highway fully loaded gets better mileage than I can get in my Jumbo skiff. A diesel engine would doubtless make it more efficient, but diesels are not commonly made as outboards, and the usual ways to install them are as outdrives (inboard / outboards), which are very expensive to buy and to maintain, or with conventional straight shaft-and-rudders, which result in boats that are deep draft and difficult to trailer because of a keel or other appendages. Neither drive system appeals to me.
Enter the Seabright skiff. This type was developed by many different builders for fishermen along the New Jersey shore that had to launch over beach due to the scarcity of harbors in the early 1900s. These skiffs used conventional inboard engines (gas in those days) with straight shafts and rudders, but what made them special was that the prop, running in a tunnel, which along with the rudder was placed entirely above the bottom of the hull. Thus these skiffs drew no more water than the hull itself, which because of its flat bottom, was often only inches. The peculiar shape of the stern, with its pod-shaped underbody and cut-away transom, gave these boats a good turn of speed, several times that of displacement-type boats (think sailboats), yet they were more efficient, at least at lower speeds, than conventional planing hulls (like Tolman skiffs, for example).
Perhaps the most famous modern version of a Seabright skiff was made by Robb White of Thomasville, Georgia, for use in the shallow waters of the Florida Panhandle about five years ago (see WoodenBoat Magazine, March/April 2006). His so-called Rescue Minor (the name refers to a Seabright skiff designed by naval architect William Atkin in 1943) draws only 6 inches and powered with a 20 hp Kubota diesel achieves more than 20 mph and 20 mpg. (It should be pointed out each of these numbers drops to less than 20 when the skiff is loaded with more than just the operator.) A large part of his skiffâ€™s super efficiency was doubtless a result of its extremely light weight. Robb built his skiff like a strip-built canoe out of poplar wood cut on his own land.
Furthermore, his skiff, while adequate for his needs and apparently a good sea boat, had very low sides, saving more weight, but the freeboard is too low in for most of us to feel comfortable in. His engine installation employed a belt-drive system which he built himself derived from a garden tiller that eliminated the conventional clutch and reverse gear, a further weight saving. You would have to judge Robbâ€™s effort an extremely successful boat, but his act is a hard one to follow for most of us. Still, it gave me an idea.
What I have done is to take the traditional Seabright skiff underbody and graft it on, so to speak, to a Standard Tolman skiff topsides to give it more seaworthiness and interior volume. In the process I lengthened the Standard skiff from 20 to 22 feet but diminished the beam from 7 to 6 - 6 to reflect the proportions of traditional Seabright skiffs, which were relatively long and slender. In the process I think I have improved the bow by eliminating the hard knuckle of the original skiffs, which tends to make such boats yaw (bow steer) in a following sea. In other words, the bow looks much like that of a typical Tolman skiff, and we know these handle well. The bottom is flat, not veed, and although I have railed against flat bottoms in the past, the Seabright skiff has a feature which is said to mitigate pounding. The aft end of the tunnel has a slight downward curve, which deflects the water coming from the prop with the effect of forcing the bow down. Thus the hull punches through the seas, rather than rising over them and slamming down. (Robb White verified that this principle works.) This bow-down aspect can generate spray, but I have included the usual double sets of spray rails that are so effective on the Standard Tolman skiff.
Twenty to 25 hp engines are appropriate for this skiff. I intend to power my prototype with a 20 hp Yanmar diesel with a conventional clutch and reversing gear. I had to buy a new gear which has a 1:1 ratio rather than using the stock 2:1 reduction gear designed to push displacement hulls. The Seabright tunnel permits only a small diameter prop, which must be run fast to get planing performance. This is an off-the-shelf item, however, and not too expensive. I expect to cruise at 17 mph. Economy will be outstanding as this engine burns 5/8 gph at about 1,900 rpms.
A new diesel setup like mine is about double the cost of an outboard of comparable power. My engine is used, but a new diesel has a long payback given the amount of hours the average boater drives per year. But for some there may be other choices, like diesels made in China, which are significantly cheaper. To my knowledge these are not yet marinized, but itâ€™s perfectly possible to do this, as Robb White did with his Kubota, or have it done. Air-cooled gas engines are cheap although noisy. Making a drive system like Robbâ€™s would save money and weight. It might even be possible to run a Seabright with an outboard in a well. But I think fuel savings alone arenâ€™t necessarily the Seabright/Tolmanâ€™s biggest advantage. Thereâ€™s a lot of thin water in Alaskaâ€”tide flats and rivers, and a skiff that draws only 6 or 7 inches has a tremendous attraction for a hunter and fisherman like me. And as a lot of boaters know, thereâ€™s a lot of other places on earth with shallow water, as well. So maybe the Seabright skiffâ€™s time has comeâ€”again.
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