{"id":2629,"date":"2026-09-20T10:38:12","date_gmt":"2026-09-20T08:38:12","guid":{"rendered":"https:\/\/yachttechnik.platen.de\/?page_id=2629"},"modified":"2026-09-28T17:19:30","modified_gmt":"2026-09-28T15:19:30","slug":"__trashed","status":"publish","type":"page","link":"https:\/\/yachttechnik.platen.de\/gb\/__trashed","title":{"rendered":"DIY Skylight"},"content":{"rendered":"\n

DIY Project: Building a Mahogany Skylight<\/p>\n\n\n\n

In the winter of 2025, we sold our beautiful and beloved Finngulf 39 and bought an old Dutch steel cutter.<\/p>\n\n\n\n

What really caught our eye about the cutter was the large salon with its many large windows. On the roof of the salon was a rather heavy and ugly hatch, measuring about 1.80 x 1.00 m. The hatch could be tilted open and on top there were two ancient photovoltaic modules installed.<\/p>\n\n\n\n

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It quickly became clear to us that we wanted to replace this unwieldy and ugly thing with a classic mahogany skylight consisting of six large window wings..<\/p>\n\n\n\n

As a custom-made item, something like this is, of course, prohibitively expensive, so the only option left was to build it myself. I looked at some nice examples and ideas in the online magazines Wooden Boat<\/em> and Classic Boat<\/em>:<\/p>\n\n\n\n

How to build a skylight – Classic Boat Magazine<\/a>

Building a Butterfly Skylight \u2013 Mastering Skills with the WoodenBoat School<\/a><\/p>\n\n\n\n

From the very beginning, I had the utmost respect for the dovetail joints on the frame pieces. To get even a basic idea of how it worked, I looked at the classic instructions for open dovetail joints on a german woodworking advice website:<\/p>\n\n\n\n

Offene Zinkung – Traditionelle Holzverbindung<\/a><\/p>\n\n\n\n

Then, based on a sketch, I roughly calculated the quantity and dimensions of the wood I would need:<\/p>\n\n\n\n

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My plan was to build it out of solid mahogany. I bought the wood from a dealer near Paderborn who was able to roughly cut the pieces to size for me and plane them to the exact thickness I wanted.<\/p>\n\n\n\n

From the very beginning, the biggest challenge was clearly the dovetail joints\u2014that is, the traditional way of joining the wooden parts of the frame using so-called dovetails. I practiced it over and over again with a Japanese saw and a chisel, first on pine planks, then\u2014as I gradually got better\u2014on the harder and finer mahogany. But even after more than 30 attempts, I was unable to saw or cut all the edges exactly at the desired angle. There was always an unsightly gap or space somewhere.<\/p>\n\n\n\n

I finally found the solution on Jonas Winkler’s YouTube channel<\/a>. The tenons and dovetails can be milled out of the end grain relatively easily and very cleanly using a suitable router bit (click on the image to watch the video):<\/p>\n\n\n\n

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Of course, it looks much easier in the video than it actually is. But with a little practice and some homemade templates to guide the router precisely, you can achieve impressive results very quickly.<\/p>\n\n\n\n

Once I was confident being able to handle the dovetail joints, I began cutting, planing, and routing the wood. In addition to the router, the most important tools were a circular saw, a miter saw, an electric planer, a random-orbit sander, and an electric file for certain fine details..<\/p>\n\n\n\n

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Before permanently bonding the frame parts together with two-component epoxy adhesive, the parts were carefully assembled without adhesive and aligned on a prefabricated base to ensure that the dimensions and angles were correct when glued together.<\/p>\n\n\n\n

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The platform used for alignment must be secure and stable, yet flexible enough to allow the four main parts of the frame to be assembled and glued together one after another. Once a joint has been glued, it should ideally not be moved or subjected to stress while the next part is being inserted. It\u2019s not as easy as it sounds!<\/p>\n\n\n\n

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When raw mahogany first comes into contact with epoxy resin, it takes on a reddish hue: a rich, dark red in the end grain and a soft red along the grain.<\/p>\n\n\n\n

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A slightly thicker PE layer is enough to prevent the parts from sticking to the workbench.<\/p>\n\n\n\n

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The ridge beam is made from two separate pieces, which are shaped individually and then glued together in place. The lower section houses the cross-braces.<\/p>\n\n\n\n

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Before the upper section of the ridge beam can be installed, grooves must be milled into the lower section and the cross-braces to allow rainwater to drain away later.<\/p>\n\n\n\n