Sat Feb 10 2024 – I am well aware of my Cape Horn Round window date of 31 Mar is rapidly closing as a result of all my delays with injury and weather, which plays heavily on my decision making after so many years of effort.
Whilst I was troubleshooting and testing my Raymarine autopilot, and then switching over to set new parameters for the NKE autopilot, I was paying closer attention to the helm tiller than normal. I noticed there was significant play in the helm between course direction changes with the Raymarine system compared to the NKE system.
I have two Raymarine Type 2 linear drives port and starboard – one for the Raymarine Evolution pilot and the other for the NKE Gyro Pilot 2. The autopilot drives are connected to the carbon/grp composite tiller arm assembly that clamps around the carbon rudder stock. I strengthened that arrangement before leaving Spain.
Each drive end has a rose joint tie rod end screwed into the linear drive that attaches to a substantial 13mm diameter tiller pin that is bolted through the tiller arm. The other end of the Linear drive is mounted to a solid bracket, and bolted through the bulkhead using large backing plates. I had applied Loctite thread locker to any critical fastener.
After approx. 11500nm of abuse, the tiller pin became loose and the pin thread has cut and elongated the hole, which amplified the cutting motion up on top of the arm, to a depth of about 5-8mm. It’s not the place to stick your head and try to make an in-situ inspection for safety reasons. So I need to make a stop and make a permanent repair by installing stainless sleeves and face plates epoxied into the tiller arms. The pins then have zero contact with the composite material.
If I was enroute to the Horn when this damage happened, I would do a battle damage temporary repair of an epoxy sandwich using two carbon plate backers either side of the tiller arm and then tighten the tiller pin with drive disconnected until cured. My risk assessment says make a permanent and stronger repair in Hobart.