A Patchwork Quilt

Where Next?
Bob Williams
Fri 13 Aug 2010 01:09

Most of today I spent scraping and scouring the hull below the waterline. My right shoulder is protesting loudly. Digging away at all the layers of paint is rather like conducting an archaeological dig, as layers get scraped off I wonder how far back in time I am going, and where Sylph might have been, who owned her and what she was doing when this particular layer of paint was applied. Certainly a lot of it goes back to well before my time and I have owned Sylph for 12 years. One day I will perhaps blast the whole lot off back to bare metal but not for a while yet. By mid-afternoon the hull was looking much like a patchwork quilt:



I have now applied some high build primer to the patches and once I have acquired some anti-fouling paint I will get here looking a bit more shipshape.

And to end the suspense, the story behind the windvane rudder, why I have cut the bottom off it.



The fundamental problem is that the rudder is supposed to be semi-balanced but some time back it has in fact become over-balanced. This means it has a tendency to want to turn one way or the other. I have overcome this tendency with a length of heavy shock cord which I adjust depending on the speed Sylph is travelling at. It works fine but is a bit of a nuisance. Now exactly why this should be the case I am not sure. About two years ago my theory was that the rudder post had a forward rake to it. I fixed this but it made no difference. My current theory is that the rudder has changed shape, in fact gotten thicker and maybe this has upset its hydrodynamics. Again some time back when I was in Trinidad I filled the rudder with foam. The rudder is made of stainless steel and used to be buoyant, but by then it had developed a few leaks and therefore become much heavier. The idea behind the foam was to give it a little bouyancy and thereby reduce the effective weiht aft (Sylph's trim  is rather sensitive to weight aft).  My hypothesis now is that the foam has over time absorbed water, expanded and caused the rudder to become thicker. So my solution is to cut the bottom off the rudder, remove the foam, which I have done, then try to restore the shape of the rudder, i.e. make it a bit thinner, then seal up all the leaks, weld the bottom back on and see what happens. Claro?  To be honest I am not overly optimistic but I can think of no other explanation.  (Perhaps you can see why I thought this was a bit much to include in yesterday's blog entry along with ball bearing blues.)

All is well.

Bob Cat:

A sunny day on the patio, quite nice. Tuna, but oily, for dinner - not sure which is better, oily tuna or hardtack. Keeps body and sole together I suppose. Now what does a nice sole taste like I wonder? With that thought I might just have a little … zzzzzzzzzzzzzzzzzzz