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Samantha was built by Pompie’s in 1950 as a private vessel. Constructed of 1 inch Kauri planking she measures 30 foot in length, 10 foot 6 inches beam and has a draught of 4 foot. The weight is approximately 10 tons. Propulsion is a Kelvin R4 diesel engine which has an output of 75 hp @1500 rpm with a capacity of 7.24 litres and weighs 3000 lbs attached to a Borg Warner velvet drive gear box.
A broken steering hydraulic ram attachment mount on Samantha caused the rudder to hit the propeller which in turn bent the propeller shaft. The underwater damage was revealed when Samantha was first slipped two months ago to investigate a vibration problem. Whilst on the slip the source of a water leak was discovered to be a corroded stern tube. Also when the propeller was inspected a fatigue crack was discovered running along the length of the hub on the outside.
An attempted weld repair of the propeller was unsuccessful because it was made of brass. The most likely cause of the crack was the incorrect fitment of a bush in the propeller together with over tightening of the propeller nut.
As mentioned the propeller shaft was made of brass with an intermediate steel coupling and shaft measuring 40mm. The shaft being made of brass explained why it was bent. It was also well worn in the cutlass bearing and stuffing box areas and was scheduled for replacement anyway. Due to limited time available on the slip it was decided to temporarily repair the water leak and re slip Samantha at a later date when all the under water components were organized. She was returned to the water and after a few days the leak slowed to a trickle.With time on our side we could plan the repair operation to the underwater components and allow two weeks to complete the repairs on the slip.
The propeller measured 23inches in diameter with a pitch of 18 inches. The stuffing box was worn and the cutlass bearing required replacement. The steering also required replacement. The other main problem we were confronted with was that with the now onset of winter and the more frequent periods of rain, the wheelhouse leaked more water into the forward cabin than the leaking slipway roof ! So it was decided to rebuild the wheelhouse to lockup stage while the underwater gear was being replaced.
All the drive train components being of Kelvin standard supply were measured in imperial. This presented with a problem in that the 40mm diameter of the propeller shaft did not equate to any standard measurement of shafts. We elected to reduce the propeller shaft diameter to 1 1/2 inches which allowed for standard cutlass bearing fitment and bushing of the stuffing box to the new size. A propeller shaft and propeller was sourced and we could now plan for the repairs.
Samantha was again slipped on 13th June 2007 and with the experienced help of Peter Delahaye the underwater repairs and the rebuilding of the wheelhouse were completed as planned on 30th June 2007.
Many thanks to all those members who provided most welcomed advice on the project and to the members who towed Samantha in and around the creek.
Graeme Hebard
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