Puffin - A carbon fiber tender and electric outboard

Who: Doug
Where: Brisbane, Australia
Multihull: Outremer 4X 
Blog : www.sailpuffin.com

 Our tender is the OC330 model, built in New Zealand, and the hull weight in carbon is an amazingly low 86 lbs (39kg). Adding beach wheels and accessories pushes this up to around 110 lbs (50kg). I initially thought we would go with a Torqeedo Travel electric outboard. Dropping down to 3hp equivalent power seemed too restrictive, so I changed my mind and purchased a 6hp Yamaha four stroke outboard. It has worked pretty well though, and with two of us onboard we can get up on the plane, but it takes nearly full throttle to do it. The problems with this setup are that the motor weighs 60 lbs (27kg) plus another 33lbs (15kg) for the fuel tank, so it’s heavy. It’s also pretty large, and vibrates a lot and is very noisy when it’s working hard. The carbon tender doesn’t flex when bouncing into waves, so the ride can get uncomfortable when going fast. We find ourselves motoring below planing speed most of the time, which is comfortable and gets us around quite quickly. This made me reconsider the Torqeedo electric outboard option. Since I’m mostly at half throttle on the 6hp Yamaha, maybe the 3hp Torqeedo would do the job? The Torqeedo is 37 lbs (17kg) for the motor & drive unit including the lithium battery. In fact, it’s no trouble to take off the tender and store it inside the boat in its carry bag when not in use. It is able to push us along at 6-8 knots. There’s no way it will get us on the plane though, so we have to adjust our expectations of how we use our tender. It’s very light. The motor is easy to lift and lower and to fit and remove from the tender. No need to deal with fuel tanks, starting, maintenance and reliability issues. No noise and no smell. The motor can be easily taken off and stored in the main boat so is more secure. The battery can be recharged using a portable solar panel. The OCTender is much drier than a RIB, which means traveling at less than planing speed is not uncomfortable. Often on a RIB you have to get on a plane to avoid getting soaked by the chop. Moving the tender around on the shore is very easy. For those that like stress-free cruising, taking it easy on the tender is more fun! But motoring into steep waves and wind is slow. In these conditions, the lack of power could cause safely concerns. It’s limited to short trips. And you have to wait for the battery to recharge after use. This can be solved with an extra battery so there is always a fully charged battery available. The OCTender is less stable and more weight sensitive than a RIB.