Fórum Boat Design Net

Some people find the new foiling AC boats fascinating. I find them somewhat interesting, as they show what can be accomplished with high technology and gobs of money. They go quite fast, maybe in the high 30s to low 40s in knots. Quite incredible for a mono-hull sailboat. But Mr. Yrvind's projects fascinate me much more. He seems to be trying to find out how little is needed to make an ocean going sailboat. His boats tend to have little ballast and very short rigs in both aspect ratio and... Read more

Hi all, a total newbie here...so please play nicely I'm in the very early stages of designing an amphibious vehicle and looking at the feasibility of using a PP65 jet drive via a transfer box 'power take off' unit. It will be based on a Land Rover Discovery 1 300TDI which has 111 BHP at 4000 RPM and 195 lb-ft (265Nm) of torque at 1800 RPM. The vessel will be a maximum weight of 2700KG. The hull will be 6m x 2m and approx two thirds of the wheels will remain in the water. Now, I know... Read more

My very first model in rhino,done after 7 days of using the trial version. I tried to focus on clean deep v hull shape and basic deck layout. Any feedback would be greatly appreciated.

Cześć wszystkim, Obecnie jestem na etapie projektowania i 4-metrowej przyczepy do żeglowania dziennego, zbudowanej metody szycia i klejenia. Główne założenia projektu do otwartego kokpitu z odpływem, ultraniska masa kadłuba prostaca prosta obsługa i wodowanie z rampy oraz prosty osprzęt z dodatkowym grotem. Zanim zamrozę modele CAD i zostaną udostępnione prototypy, zostaną uwolnione z Waszych skutków: Czy w społeczności istnieją duże zasoby na kompaktowe, mikro-dzienne żaglówki poniżej 4... Read more

32" long 3.1 # craft is early in development but looks good so far. Approximately 1.4 mpg on less than a watt. The foils shown below top to bottom Wider 6310 foil not yet trialed 6310 foil currently on craft Crescent plan foil not quite as effective as 6310 Flexible fin less effective Next trials will try a faster geared drive and will relocate the batteries to hulls to move CG aft then perhaps the higher A/R foil. Ultimate goal is to repower the craft with paddle... Read more

Is it possible to use welded metal belows for sterndrives, if custom one could be built to replace the existing one? Could that be a "permanent" solution? Here is one example of what are some possibilities: Configuration - Werte Kollegen und Kolleginnen, konfiguriert Eure individuellen Metallbälge! https://www.bellows-configurator.com/ Hmm, what would be the best material (316L sounds nice, but could lead to galvanic corrosion, depending on the type of attachment between the drive... Read more

It has been quite awhile since I looked for this subject,...and even my search thru the forum didn't bring up the word in a subject thread titled thusly. I was looking thru some material on a new 60' hi-performance cat claiming capabilities of single-handed operation with a hi-aspect sloop style rig, and they mentioned this 'UpSideUp' system with multiple capabilities. I went looking for what equipment was specifically doing the work of safely releasing the loads. Here is what I found... Read more

Hi everyone I have a 6.8m fibreglass boat out of the mould and nothing done to it so I’m assuming thats why it doesn’t have a build plate? I have been trying to find out what it is and my local boat dealership has no idea what it is Im hoping someone can help me identify it thanks

The technology for our electric boats is directly linked to the technologies being worked on in the automobile world,...which is advancing quite rapidly. We need to keep abreast of positives and the negatives. This subject thread is hopefully one that tries to keep abreast of both. Not only the positives and negatives of the electric power sources (batteries, etc), but also the motor technologies. BOTH of these technologies are needed for our successful boat applications. And there are... Read more

Does anyone know where I can get Cecil Bodens boat plans in 2025, specifically the "Mussel", a small dinghy. The web page in old threads appears to be dead, and google brings up nothing.

Hello, everyone. My father owns a Monte Carlo Offshorer 30 with two 4.5 MPI engines. These engines were originally mounted upside down with angle drives for inboard propulsion. These angle drives were worn out and could not be repaired or replaced. So, he moved the engines back and installed them in the conventional orientation. He set out to build a surface propulsion system, which didn’t survive the first 2–3 test runs. But in terms of performance, it was perfect. So he modified... Read more

Now that the kids are all grown, and moved out, we've sold our alloy powerboat which was suitable for up to six people, and we are downsizing to something suitable for two. The plan is to find an old V16 or V17 Haines hunter and do a rebuild. The idea is to make a little pocket-battleship hardtop for fishing. There are plenty of similar builds documented for inspiration and ideas. As part of that, I want to add floodable keel chambers (1). I'd value some advice on whether that is a bad... Read more