Boat Window Replacement

A boat’s windows can become matted, crazed, and get an overall used, and worn-out appearance over time - and this is not the biggest concern, at this stage, a replacement is not necessary. Plexiglas sheets can also break for any number of reasons, leading to soaking. As well as the obvious, sudden impact breakage, there's the insidious factor of a gross difference between the thermal expansion of the plexiglass and the hull, which can require replacement of the plexiglass, for which our company offers a number of solutions.

Glued Plexiglas replacement

On older boats, the traditional method of fixing windows in place is to use screws. However, there is a major drawback to this method as the screws do not leave enough room for the glass material to expand thermally. This leads to small cracks appearing around the screws over time.

If the window can be replaced one by one, the original Plexiglas sheet can also be used as a milling template. If the shape changes, a new milling template is made. In the process, the outline of the new window is first taken from the hull with a slat frame or, in the case of a simpler shape, a foil. This is the basis for the milling template. The edge of the milled window is rounded and then the inside is coloured so that the glue does not show through. Before fitting the windows, the previous holes in the hull are filled.

The load-bearing part of the glueing and the proper gap are provided by a special double-sided adhesive, and the sealing is provided by Sika products, according to the layering sequence specified by the manufacturer.

Aluminum framed hatch

Plexiglas sheets can be fixed with a special rubber profile or they can be glued. Rubber profiles can last for decades, in most cases they can be reused after a thorough cleaning, but worn out pieces need to be replaced. We keep service materials for Moonlight products in stock.

Glued Plexiglas boat hatches must be cut out of the frame, which must then be cleaned. The new plexiglass is glued and sealed with Sika products according to the manufacturer's instructions.

When replacing aluminium-framed hatches, the original plexiglass sheet is used as a milling template.

Reference works

C.N.S.O. 8.2 Modernisation

In the case of the C.N.S.O. shown in the pictures below, the windows were fitted using the traditional screw-on technique. To achieve a more uniform and modern look, we turned all the windows on the boat into one larger window, cut into three sections to reduce the effects of thermal expansion.

The first step was to make a slat frame and use it to create the outline of the new plexiglass. The second step was to create the milling template based on the outlines created in the first step. After rounding the edges, we fixed the new glass in place using the technique described above.

Moonlight boat hatch

The aluminium framed Moonlight glasses in the pictures belonged to an Elan Impression 384 sailboat.

After cutting out the original glass, we cleaned the frame and milled a new plexiglass.

After preparing the surface, we carried out the gluing process in two steps. After fixing the plexiglass to the frame, we filled the gaps between the glass and the frame and spread the adhesive evenly to create a smooth, seamless surface.

The replacement process took only a few hours.

Feeling 27 window replacement

This Feeling 27 was our biggest challenge yet. The original windows were bonded with a very strong, but not waterproof, double-sided adhesive. The plexiglass was also badly damaged and we had to remove it piece by piece. We love puzzles, but not so much when it comes to a milling template.

The next problem we encountered was that the layers of fiberglass that make up the hull had completely separated around the window frame. We are not sure if it was a design flaw or water damage, but the glue had ruined much of the gel and the outer layer of fiberglass. Removing the tape was only the bonus task.

The real work began with the repair and painting of the hull. Fortunately the owner was very fair and understood the extra work we were about to do. After the repair, the windows were manufactured and glued as usual.