The picture shows the dodgy section of hull in the aft accomodation space I posted about in January.
What I've done is taken a series of thickness readings, using a Cygnus 1 ultrasonic thickness meter, so as to gain a picture of the overall state of that section of steel. If you click on the picture, you can see the thicknesses in milimetres written in chalk on the plate. Bear in mind when you look at this, the hull readings I've taken elsewhere on Lady Jane mainly read between 8mm and 9mm.
As a result of the readings, and some lengthy discussions with Robin, I've finally decided to bite the bullet and cut out the section of plate that is below 7mm thick, and replace it with new 8mm steel plate. To do this, we will probably need to cut away both of the ribs, then replace them afterwards.
What will make this job particularly interesting is that all of the plate that needs replacing is below the waterline, so we will need to start this once the tide goes out and, more importantly, have the new plate welded back in place before the tide comes back in again.
The consequences of this job going wrong does not even bear thinking about.
Technorati Tags: Lady Jane; Hull; Waterline; Rust