A nice modification for a traditional transom is adding a small addition which provides a convenient swim step and dinghy boarding area. If the projection is kept to a minimum it should not interfere with carrying a dinghy on davits.
With this in mind, I removed the old and very tired swim step. Next the old gel-coat is removed from bonding areas and the surfaces sanded and cleaned. Now I can begin construction of the new “sugar scoop” swim step by projecting the hull lines below the waterline past the transom. To accomplish this, pieces of plywood are attached with screws to the bottom, forming a temporary mold for the extended transom. The engine exhaust (large hole to left) will exit through the bottom of this extension on the port side via a custom fabricated fibreglass exhaust tube. It will be made later and reported separately.
Plywood easily conforms to the gentle curve of the hull in this area. The temporary plywood forms are covered with plastic sheet and “peel ply” so they may be easily removed when the resin cures. Laminated panels of gel-coated fibreglass will be added later to tie the bottom along the hull sides, forming the basic “sugar scoop”. While this is curing, more supplies are ordered.
Two staggered layers of 1708 fibreglass cloth are laid into the forms and saturated with vinyl ester resin. Note the tabbing to the transom. More layers will follow and cover the entire area of prepared transom. Two layers of 1708 will be applied to the entire bottom of the boat, thereby replacing the strength once provided by the removed hydrolysed original polyester layers that were removed last winter.
The white gel-coat side panels are made using a mirror. The mirror is waxed and buffed so the panel can be easily removed from the mirror. The polished mirror surface is what produces the excellent finish to the panels. A paper pattern was made of one side panel and used to make a plastic template. The template was then temporarily attached to the hull to check the fit with minor alteration. The template is laid on the mirror and a tape border to confine the gel-coat is applied to the mirror, then waxed and buffed.
White gel-coat is catalysed and painted on the mirror within the taped area.
Successive layers of surface veil and a single layer of 1708 biaxial glass are applied and saturated with vinyl-ester resin. Lastly, a layer of peel ply is pressed onto the layup creating a good secondary bonding surface. After several hours the panel is cured enough to remove from the mirror but soft enough to be easily bent to conform to the hull shape.
The trimmed panel is temporarily taped to the hull where it cures in the shape perfectly matching the hull.
A reverse image of the first panel is made in the same manner and when ready, taped to the other side of the hull. After a few days, the shape will be set and the panels can then be bonded to the hull in their proper place. Piece by piece, the new sugar scoop is taking shape.