Rudder problems?

[mob]

There's a weird problem with my rudder, perhaps a defect in the ply. Every time I take her out, the surface seems to explode - always in the same place, always on the same side. :B
If I don't repair it it doesn't seem to happen. If I do repair it the problem is guaranteed to reoccur. Does anyone else suffer this?

[Daddles]

One would imagine that your rudder now has water soaked into the timber, so maybe the 'ultimate cure', a new rudder, isn't such a bad idea. If you've got the ply, you'd knock one up in an afternoon.

As for the problem itself, I'll leave that one ... :wink:

Richard

[PAR]

I always design strip planked appendages for small craft, never plywood. This is because of the way plywood reacts to cyclic loading over time. The cross grain portions of the plywood laminate suffer from "rolling shear" and this dramatically weakens the piece.

What you are experiencing sounds like a localized failure in one of the internal veneers, probably at a void or veneer seam, just below the face veneer.

If you want to save this rudder, grind down through the outer veneer and you'll probably see the problem, which will be a void, pith pocket or other natural or man made defect. Grind out the bad wood, dry the area and fill with thickened epoxy.