www.kp44.org — The official website of the Peterson Cutter Owner's Group

by Britt Finley
S/V Restless

KP44 (early 1976)


This article is meant to provide information about the rudder failure we recently experienced and how our repairs were made. The previous excellent article by Greg Rodgers, entitled "Rebuilding the Rudder", provides very good information and was a great help in making our repairs. Also, the article by Rick Crane, "Removing the Rudder", was very useful.

History

In April 2003 we broke the rudder on a sail from New Zealand to Lautoka, Fiji. We were about 180 nm from the pass when the failure occurred. The wind was downwind at about 30 kts. We were sailing on a wing-and-wing configuration with a double reefed main and furled headsail. Also, at the time, our engine was inoperative due to a salt water pump problem. The rudder failed internally when the upper stainless steel sheets broke. This allowed the stock to rotate independently from the rudder and caused complete loss of rudder control. We immediately took all sails in and raised the staysail. This configuration gave a boat speed of about 3.5 kts and took us all the way to a point just outside the pass though the reef. At this point, we were towed to the Vuda Point Marina near Lautoka. The next day, we were hauled out and repairs begun by Pacific Marine, the local boat repair service. After about 3 weeks, Restless was back in the water and sailing again. The repaired rudder seems to function and feel the same as the original.

The Failure

The photo shows the rudder stock and part of the stainless steel sheet structure that was welded to the stock. The failure occurred in the sheets just outside the welds. There was considerable brown staining and pitting visible. The rudder had been weeping water during the past several haulouts and corrosion was undoubtedly at least partially the cause of the failure. However, let me admit that I think I contributed to the failure by over stressing the rudder. During a heave to, I allowed the boat's stern to point toward the sea with a fully deflected rudder against the stop. (We reached this condition after heaving to with only the staysail which later backwinded and caused the boat sail downwind.) There were much higher than normal forces on the rudder. The internal rudder structure was probably damaged at this point. The rudder failed later in the same day. So with this confession, maybe the rest of you KP44 owners should not worry too much right now. Just be careful and avoid putting any extra load on the rudder. If your rudder is leaking, like mine did, perhaps you should fix it soon. You will have more peace of mind.

The Repair

The above picture shows the new rudder stock assembly which we had fabricated to replace all the old internal stainless steel. A long 1-1/4 in. s/s shaft was bent to match the old parts. A smaller diameter was machined in this shaft to match the lower bearing and a larger diameter piece was welded just above to provide the thrust bearing. The stainless steel sheets and bar were welded on as shown. It is very important that the upper stock and lower bearing are concentric. The photo shows that this was not the case initially. The Lautoka machine shop claimed that the misalignment was caused by heat from the welding. Anyway, it took at least 3 trips between the shop and the boat before they got it right. In the end the piece worked fine and I feel we made an improvement over the original metal piece design since the torsion load from the rudder to the stock is better distributed. Time will tell.

This picture shows how the new metal piece was placed into the old port side of the rudder. The rudder was disassembled by cutting out pieces from the starboard side, removing all the old plywood, other wood, and filler material. West System epoxy resin and microballoon filler was used extensively to fill the rudder along with some polyester filler. Fiberglass mat was applied over the metal areas. Then the old rudder pieces were put back on by squeezing out the filler to avoid voids. Later about 2 layers of fiberglass cloth were applied over the whole rudder exterior. The materials and method were much the same as described in Greg Rodgers' article except we re-used the old shell from the starboard side. We did not weigh the new rudder but it is much heavier than the original.

There was also some fiberglass repair required on the area around the rudder stock tube and rudder support area. These seemed to be the result of water intrusion into the filler material, which was used originally.

The Cost

I was at a foreign port, on vacation, and lazy. So I did very little of the work myself. The below accounting is just for the actual rudder repair and can be compared with the accounting that Greg Rodgers gave for his rudder repair. I have converted all $ amounts on my bill from Fiji to US at the rate of $US 0.54 = $Fiji 1.00. Keep in mind that our repair included the fabrication of a new metal piece and was more involved.

Item Cost (US$)
Labor to repair rudder (142 Hrs @ $8.10/Hr) $1,150
Materials $1,204
Fabricate new rudder stock including materials $1,133
Total Rudder Repair Cost $3,487

The fiberglass repairs on the boat around the rudder took another 12 hours and cost an additional $217 with materials. There were also other associated costs for the prop shaft removal and haulout. In Fiji labor is very cheap. It is possible to hire good workers for about $US 1.50/hr. But, imported materials are expensive there. Next time, the guys could do the job in half the time. And charge a lot less.



 
Last modified: January 01 1970 00:00