I wanted to post more photos from the inspection of the two Irwins I inspected in October 2013.
The first step was to take Infrared Images of the area the chainplate is embedded in. Images were taken from the exterior and interior of the boat. This is harder then it sounds, there is a bit an art to take images that will give us the information we need.
The following are from the exterior:
You can make out the chainplate as it disappears into the hull. The green area and blue areas indicate moisture. A heat source was used in the interior of the boat to help us see the moisture.
In this image the moisture is indicated by the yellow color. This image was taken after the sun had warmed the hull.
The following images are from the interior:The interior was imaged with the sun warming the hull. Where the sun did not warm the hull I added heat to the surface. You can make out the chainplate behind the liner in the locker.
In the next image we can change the palette to make the trapped moisture more noticeable.
The purple "blob" being the moisture.
This what we can see with our eyes:
No signs of water intrusion.
Below is a closeup of one of the chainplates. This one does not look too bad either.
Here is what one looks like after it is pulled out of the boat. On the side against the hull there was not much corrosion sighted, but I was able to find cracks. One way I could have found the cracks would to have used dye penetrant to highlight the cracks.
We cut one of the chainplates in half, I was surprised to see the amount of metal wastage.
One of the new chainplates being installed.