Birdwatcher-2 Motor Mounting
Birdwatcher-2 Sailboat, designed by Phil Bolger
The Birdwatcher-2 (BW-2) has an aft deck that primarily accomodates the 2-HP Honda outboard, but also provides an outside area to store and use items that might be best not inside. This page shows details of the motor mount. A separate page has pictures and information on the after deck.
The mounting board is 1-inch thick plywood. The motor extends about 14-inches below the bottom at the stern. The bottom at the stern is roughly the design waterline. The motor mount is vertical, but the motor shaft is slightly off vertical, as shown. I added 1/4-inch ply in the bottom of the motor well. This seals against water, but probably more important it seals the boat against possible spilled gas. The gas and fumes would otherwise end up in a "wet locker" below the motor. To prevent gouging the motor mount board, sheet stainless steel, 1/16 -inch thick, has been screwed under the motor clamps.
Bolger has long pointed out the awkwardness of an outboard on a pointed stern. This is a top view of the motor in the forward direction showing the problems. The hull has been cutout to move the motor closer to the centerline. The cutout looks large, but every bit ends up being used for the motor or for my fingers as it rotates. The next picture shows that 360 degree rotation is still not possible.
The Honda motor is reversed by rotating it 180 degrees, i.e., there is no reverse gear. The motor can rotate about 30 degrees past this point and then the handle hits the vertical deck support. To minimize this problem, I attempted to cut away as much of the support as was practical. Operating the motor in reverse around docks will not be very convenient considering that the tiller is in the next compartment. The oars should be helpful for handling the boat in tight quarters!
Motor stowage fits well. There is sufficient space to stow the motor either with the prop sideways, as shown, or in its forward running position. If the motor is rotated as shown, it must first be tilted straight, as the clamping arrangement on the motor shaft prevents removal when rotated. It will be easy to rig an extra support for the motor shaft, to be used when trailering
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This was last revised 26 November 2005. Bob Larkin, Corvallis, Oregon