Wednesday, 27 March 2013

Trials and Error - An upheaval in the starboard cabin

Bedding fills the saloon
It seemed a bright idea, a second autopilot head installed down below in case the existing one failed which would also provide info such as wind speed and log data at the chart table even when the laptop is off. Raymarine's self steering computer (aka the brain) allows for two separate circuits so this second "control head" should in theory be easy to install and whilst we were at it we'd solve the problem with the wind display in the cockpit...

First empty the starboard cockpit locker (toolbox, warps, safety gear and more) then trace the existing connection forward from its position close to the wheel. Down below empty the starboard aft cabin of pillows & duvets, empty the same cabin's lockers of towels, bed linen and stuff to access the autopilot's brain, unscrew or otherwise remove most of this locker's shelves and backboard to gain access to a Seatalk* junction box, clear the chart table and surround so the rear of switch panel can be accessed and finally remove the radar so the rest of the Seatalk cabling to and from the laptop and GPS is getatable when needed. And pile everything up in the master cabin up forward or on the saloon table, providing yet another opportunity to refold all the towels, sheets & duvet covers!
A tidy pile of towels....

...were joined by sheets, duvets and t-towels

Head down in a locker
Eventually after a few false starts the cable was traced, a second one connected the new head to the computer and after a trip to Raymarine's premises in nearby Titchfield the wind instrument was working again. There was one "Seatalk" fail when we switched on the MOB Lifetags but after checking the wiring again and some extensive overnight testing everything was hunkydory. Everything could be returned to its home and the boat could loose its jumble sale look once again.

A major sea trial was called for so Temptress motored to Shepherds Marina, Cowes in a bitter easterly, her crew treating themselves to supper at Mojac's. First off Southsea beach a few tightly executed curves checked out the new rudder, then we settled down on a straight course, the wheel felt light to handle despite the wind and fairly lively sea. We then attempted to trial the autopilot but it wouldn't lock on the wheel. in the wide expanse off Fishbourne depsite the ferries we performed the slow circles and motoring directly to windward to recalibrate the repaired wind instrument so that the arrow on the screen pointed pretty much in the same direction as the apparent wind at the top of the mast.

Radar on its face again

Locker dismantling

Amazing what is hidden away!
Once in Cowes, the starboard cabin was emptied again and the skipper crawled through to the services area to review the steering set up -  doh! The autopilot ram had basically not been engaged with the steering quadrant after the recent rudder replacement, a simple enough fix which should have been spotted before we left our berth. A further session on a flat sea is now needed to perform a final autopilot calibration but that can wait for warmer weather!
Wiring at the back of the cockpit instrument displays
Connecting up the "brain" to its new control head
* Seatalk - Raymarines serial communication protocol that enables instrument information like wind speed, boat speed, distance travelled, GPS position to be networked and shared


1 comment: