Please teach me something
 

I'm truly interested in learning something here, not looking to start a controversy. Both the Reg 23 and the Seacraft 23 (forget about Potter built vs Tracker) are both known for their great ride. The Reg has a 24* deadrise at transom and an 8'3" beam and is a heavy boat relative to others in its size category. The Seacraft, on the other hand, as a 20* variable deadrise hull and has an 8' beam and is a lighter hull.

With vastly different deadrises and weights how are both renowned for their great ride? What makes two different designs each account for a great following due to their rides?

Please educate me.

The 24 deg boats will rock a lot more at rest when influenced by waves. If tabbed down too much into "confused" waves they may dig or wander too much. At speed this can be a negative. All boats are trade-offs, the variable deadrise is a compromise in that it rides nice but will be passed by a 24@ boat in the right conditions. It takes more HP to push a 24@ hull. Those are few points and I'm sure others will chime in. Ride all you can in all conditions you can.

Thanks for the replay - love the name

Seacraft Legend
 

Scott, I've been running these boats since the mid-70's and I'm still trying to figure out how they do what they so well. It seems like as the variable deadrise "panels" change angle at the reversed strake they break the adhesion from the water that the continuous deadrise hulls have. Seacrafts seem to want to get up and dance across the surface rather than plowing a slot where ever they are pointed. The entry at the bow on the center panels is as deep as any 24 degree hull, then the Seacrafts seem to "manipulate" the water better as things go aft. While boat builders in the early 60's were trying to figure out how to style the fins on the gunnels, Carl Moesly was taking his aeronautical experiences he learned flying and applied it to hydrodynamics. His boats dominated the 500 mile Miami to Nassau races for a decade with the little Seacraft outboards. And nobodys built a boat with prettier hull lines - ever. Regulator will eventually go the way of Alim, Hiliner, Sea Bird, Aztec, Aquasport and Islander, but there will always be SeaCrafts at the ramp - with fish in the coolers.

I know this has been discussed here but I am new-ish member. This thread reminds me of a question I've been meaning to ask. Is the "Sailfish" design a knockoff of the Seacraft VDR hull? Has anyone driven one?

http://sailfishboats.com/index.php/sailfish-difference/

"Our exclusive, patented, Variable Degree Stepped (VDS) Hull provides the smoothest ride of any fishing boat on the market. Its unique design actually features three distinct running surfaces; the first, with a deep deadrise that cuts through the water and two others that provide for lift and stability. "

Jon Brush
76 Sceptre 23/225 Optimax

Copy Cats
 

Yes Jon. Sailfish, Helms, Seawolf, Sarasota Skiffs and 17 others have copied Carl's Moesly's patented VDH design once the patents ran out. If you were a boat builder, why would you copy a "Euro-Design, Micro-wave Melted Cheese" Bayliner?

Thank you Terry.

Terry has a point, its a bit puzzling why the Seacraft is so good. One factor he mentions, but probably deserves more emphasis, is the bow and how it relates to the rest of the hull. Look at pics of the bow, especially the Moesley 21 bow. Its super deep and sharp, way more than 24 degrees. My 25 is even sharper and rides into a headsea even better than a 23, not sure about the 21. Mine carries its extreme deadrise all the way to the transom, while other Seacraft hulls flatten out aft to about 20 degrees. Mine comes down from airborne much softer than others, but also rolls more. Moesley hit a great compromise with the sharp bow and flatter stern sections, rides great and is stable at rest.

Ok I will chime in. The thing that I always notice when I get back into my boat after being off the water for long time is (and my first time experience in a Seacraft) is the way the hull cuts thru normal chop big or small. You hear whats happening, but you don't feel a thing. Not a big deal per se' however I just never have had that ride in other manufactures boats...go figure :cool:

Thanks, Terry. Funny that they claim their design is "unique, patented". 😂
Jon

"Microwave melted cheese" ha ha I love that line.I think a lot of these new boats look like a big bleach bottle, or kind of like the old American motors Pacers built then put in a big furnace to make the melt into a blob with wheels.

Welcome aboard Scott and keep asking questions! Lots of wisdom on this site!

The key to the the SeaCraft's soft ride is that it traps air as the water comes off the vertical steps. The way Carl Moesly explained it to me is that if you lay a straightedge on any panel at any point along any Moesly-designed hull (21, 19 Bowrider, 20, 25 Seafari, 27 Seamaster) and extend it outboard to the next panel, you'll notice that it just touches the outer edge of the next panel. The straightedge represents the path of the water as it comes off the inner panel, and the triangular space between the straightedge and the adjacent panel represents trapped air. This trapped air not only cushions the ride, it also reduces friction between the water and hull. Tests done at Mercury's Lake X back in the 60's showed that the SeaCraft Variable Deadrise hull (VDH) was 10% faster than constant deadrise hulls of the same weight and horsepower! This was proven repeatedly by SeaCrafts nearly total domination of the outboard powered classes in the Offshore Power Boat Races in the 1960's! You can learn more about the early SeaCraft history from the Moesly SeaCraft web site. If you read the patent description on that site, you'll find more information on how the VDH design works.

I spent a lot of time under the hull of my boat when I painted the bottom a few years ago, and I discovered a couple more subtle details that Moesly incorporated into the 20' hull which demonstrate his brilliance as a designer and his understanding of hydrodynamics:
1. If you look aft along the chine from the bow, you'll notice that there is a slight wedge built into the outer panel which would act like a trim tab to increase lift and help the boat get on plane easier! (All the Moesly designs I've seen will plane at about 12 mph with original power! I doubt a Regulator will do that!)
2. If you lay a long straightedge along the keel, you'll notice that there is a bit of rocker built into the innermost panel. As speed increases, a deep-V hull will develop more lift and rise higher out of the water. Once you get up to about 40-45 mph, the chine and entire outer panel are out of the water, so the trim tab effect of that wedge is gone, but the rocker in the inner panel will allow the bow to rise and reduce wetted surface and drag for more speed! If you look at the running angle plot in the Boating Magazine test of the Seafari 20 in the Literature section, you'll see that running angle does in fact increase at maximum speed!

It looks like some flat strakes and spray deflecting features have been added on the Sailfish and Potter designs (the 23 & 18), so they may ride a bit drier, but those features also increase lift and will tend to hurt ride a bit.

Seems a few guys here on csc are familiar with the owner/ founder of Sailfish, who clearly and unashamedly acknowledged the Moesly hull. They claimed and patented a very clever design. Nowhere does Sailfish claim the the inventive genius of Variable dead -rise.

I think Thresher Boats may be doing something with the SC 20 hull down here in Newport beach. Haven't talked to anyone or seen a good pic of hull yet...