We had been planning to work on the rudder for a long time. Even when Venus was in Tahiti, we knew that saffron was waterlogged.
Blistering, fiber delaminating, a non-linear shape - all clues that it was high time to look into it!
Chloé and the rudder
As novices in the repair of Rudders and in fiberglass work in general, this work gave us a hard time, but it turned out to be very instructive and interesting!
Here's how we carried out the work, step by step!
Our rudder: the structure
We thought we had the original rudder, but after consulting Baltic and receiving the plans, we realized that this was not the case. So we had no idea what was inside the rudder before we opened it.
Plan of the original rudder, which is not the one we have now.
Our saffron measures around 1.80 m by 80 cm, not including the wick, and weighs around 100 kg. It is made up of 5 stacked parts:
Fiberglass
Light polyurethane foam
Compact polyurethane foam and resin
Light polyurethane foam
Fiberglass
Inside, a stainless steel structure ensures the rudder's solidity and maintains its shape under water pressure.
The Beginning
It's July in the Gaspé, the days are unusually cold and the sun rarely shines, giving us short days to continue our gargantuan project aboard Venus.
Taking out the rudder was harder than expected!
In order to be able to work on the saffron over the winter, we have removed it from its usual location and stored it in a heated workshop. This will allow the saffron to dry well over the next few months and we'll be able to start work on the fiber in favorable conditions indoors, while the temperatures are still freezing outside.
But first things first. In order to dismantle the rudder, we removed the three rods that run through the rudder stock, namely the one for the autopilot, the one for the wheel steering system, and the one that holds it in place and prevents it from ending up in the depths of the ocean.
And it was only after many hours of effort that we managed to get the rudder, weighing almost 100 kg, out and into storage.
Sanding and Drying
The aim during the winter months was to dry the saffron thoroughly before starting to work on it again. For optimum drying, we had to sand down and remove the different layers of paint right down to the fiber itself. As soon as we had access to a heated workshop, we started sanding the different layers and discovered that the lower layers were damp. So we removed, layer by layer, those that were damaged and needed to be redone.
Today, with the experience I've gained, I'd say it's pretty straightforward, but at the time, with my lack of knowledge and confidence, it wasn't an easy task. With hindsight, I would certainly have approached certain stages differently, but I can't help but feel compassion for myself as I look back on those months. What a long way we've come!
Anyways
How can you tell whether the fiber is still good or not? There's the tapping technique, which consists of tapping the fiber with a hammer to locate any hollow spots. Personally, I haven't mastered this technique yet, and it's easy to make a mistake when different densities of material are involved.
There's also the visual technique, which involves spotting osmosis bubbles and areas where the fiber appears white. These white areas indicate the absence of resin: the glass fiber is dry. This may be due to a lack of resin during manufacture or to decomposition into acetic acid caused by the presence of water.
In all cases, the best approach is to remove the dry fiber and replace it with new fiber that will be soaked in resin. But first things first!
To remove the damaged fiber, we used a grinder, an orbital sander, a Dremel with small 3-inch pads, and a lot of patience!
When in doubt, it's better to remove damaged material and replace it rather than leave it in place.
This is how we removed a whole layer from the entire rudder to get back to a sound base.
A small point to consider: when sanding a surface to be refibred, it is important to create a slope of 1/12. For example, if you hollow out 1 mm, the slope should be 12 mm from each edge, for a total of 24 mm. This slope allows the fibre and resin to adhere as much as possible, ensuring optimum resistance.
Polyurethane Foam
In some places, the polyurethane foam looked wet. When in doubt, we cut completely through to the foam, examined it and removed it.
We then left the area to dry for several weeks before pouring 2 LB density two-component polyurethane foam.
The Foam
The first tests in containers were not conclusive, but after several attempts, we mastered the technique and it was a pleasure to work with such a pleasant material!
The work of rebuilding the rudder then began. Read all about the reconstruction in the next article!
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