Saqa, I've done some performance calculations on 3 tonnes / 10 m catamarans (the approximate size I'm interrested in.) 40 hp would give me 14...
I believe the Albin 25 would be better suited for the proposed long range operation if stretched with a couple of meters. Keeping the same hull...
I agree with wavepropulsion that a traditional 7 m lapstrake double-ender isn't optimal for a speed of 6 knots or greater. Based on the...
The absolute first thing I would do (and did) is to build a small boat. After that you're addicted to boat building/designing and have to...
AIT is less claustrophobic for those of us who use the metric system.
The problems and danger with petrol make a good case for diesel, if that is an option. Erik
The language is Swedish, one of the dialects spoken east of the Gulf of Bottnia. About 5% of the Finnish population has Swedish as the native...
I also think you should have good reasons to travel south of 40 deg North. Better stay where the weather is nice and cold. When the ice was...
Thank you for the article, rwatson. I wouldn't have recognized the signs of drowning. Maybe I will now. Erik
300 lbs will be heavy to roll to the water by yourself or with a less strong helper. I'd put the limit at 200 lbs, with 150 lbs as a target,...
The rowing boats we had in Southern Lapland when I grew up were designed for two rowers in tandem, but often you would row them alone. We were...
I've seen small open boats in our marina with the type of pump PAR's picture shows. They were generally filled with water because the rocking...
For a PMDC motor, the torque constant KT (in Nm/A) equals the back-EMF constant KE (in V/radians/s). 18 oz-in/A = 0.127 Nm/A. 15 V/kRPM = 0.143...
Regarding tip speed for the propeller. I searched for information; excessive tip speed give problems with cavitation. A 25 hp outboard I have has...
jonr, Volts (over the motor) * amps (into the motor) will give you the power (into the motor). Hopefully, the motor is doing something useful so...
Kerosene, It is true that you double the output power while keeping the losses (almost) the same if you double the speed, as long as you work with...
It's not the power input into the motor that cause heating, it's the power losses. Power losses in a DC motor are mainly from the winding...
The municipalities close to Stockholm were asked (I've forgotten by which authority) to plan for a rise of the sea level of 2 - 4 meters in 100...
Wayne, Asking an amateur boat builder for pictures of his boat is dangerous. There might be no end to them. Here are three pictures from the...
A photo of my new 2-man kayak, built with spruce strips covered with glass and epoxy. The photo is from one of the trips close to Stockholm. Erik
