Hello
Has anyone replaced their rudders, or have had them repaired? Does Knysna have rudders for sale? We are a 2011 480 and apparently are in need of new rudders. One pole is slightly bent and the other has water in it although we see no real entry point. Has anyone fixed their rudders themselves?
thanks
Carol
I own a 2010 480. Survey when I bought the boat revealed a wet starboard rudder. I negotiated a 5k deduction on the sale. The rudder was removed, fileted, dried, and rebuilt by a fiberglass specialist. Amazingly, it cost about 5k. Ha. Importantly, it’s still working well 5 years later. I’m a novice. Many boat rudders are wet, but rudder failure is the cause of a significant number of boating disasters.
We are currently rebuilding our rudders here in New Zealand.
Our rudder shafts were stainless steel. We first noticed some water weeping from the rudder so we drilled some holes and sure enough there was some significant water intrusion. Going deeper, we ground the material all the way down to the rudder shaft and found rust…the shaft was completely deteriorated.
We are strictly DIY owners since any work we have had professionally done has not been up to our standards. Rebuilding a rudder isn’t complicated at all. Time consuming maybe…but not difficult.
Since the outer shell of the rudder was in good condition we cut large openings in one side, removed the shaft and filler material (we left little tabs of filler material to help us place the new shaft in the correct orientation) and had a machine shop manufacture an identical shaft in solid aluminium. Then had it anodized. There are specific standards for the type of aluminium and the level of anodizing.
Once the “shell” of the old rudder was cleaned and prepped we tabbed the new shaft in. Once that was cured we refilled the rudder. This was probably our biggest question mark.
Our rudder had been filled with bits of foam, some type of fairing filler (we think, based on it’s density) and polyester resin. We chose to approach it in the same way, with some minor changes. We cut up closed cell structural foam into small pieces and mixed it in with West Epoxy, and West 404 high density filler. We weighed everything so each batch was identical.
Once that was cured we ground away most of the old fiberglass, faired it with West 417 and it’s now ready to reglass.
The second rudder proved to be a bit more problematic. It was obvious that work had been done on it by the first owner and it was pretty wonky so we used the “new rudder” to create a mold and built the second rudder from there. If you want a detail of that process let me know.
I can’t say which process was easier. They both had their challenges. What I can say is we used about 10 to 11 liters of epoxy, about 12 liters of 404 filler, and maybe a 4’x6’ sheet of foam. Although, the foam is a guestimate since it was scrap from another job. Our supplies, including the shaft, were well under $1500 USD. More importantly, we have peace of mind that they will hold up for years.
While many rudders are filled with mostly foam I think Knysna may have built rudders that are stronger and more robust.
If you have more questions we would be happy to help.