Projects for the Week

John the rigger will visit the boat on Wednesday or Thursday morning to (1) mount the cheek block above the trysail track (2) Cut and fit the trysail halyard (3) file the join of the two sections of the trysail track to eliminate the discontinuities of a slight misalignment that forces me to manually pass the sail slides through (4) probably fix another cleat to the mast.

Today I got a visit from Sergio, a welder of excellent repute, and his helper regarding the fabrication of an emergency tiller that will fit over the end of my rudder post, which can be accessed by removing a plate on the cockpit floor. 

Jak and I had discussions about this and I kept working on the problem after his departure.  A few days ago Bob Carrol and I threw some ideas around and he came up with some very good suggestions.  Why, for example, settle for hand steering with an emergency tiller when I can design the tiller to be controlled by the Monitor wind steering. 

But then a couple of points emerged from the discussion that made me doubt that an emergency tiller was worth the trouble. 

For one thing, Pachuca has a Cobra pedestal steering linkage which uses a gear and shafts supported by bearings.  This is considered a very reliable system because it does not rely on chains or cables that can break or jump out of position.  Thanks to Reg Kelly in Perth, we removed the pedestal and had it refurbished shortly before my departure from Australia.  Two of the three bearings were found to be seized.  But the gears and shafts were in excellent condition and with new bearings the unit was good as new.

There is also the autopilot, which uses an electro-mechanical linear drive to operate directly on the rudder post.  So if the linkage failed without jamming up the autopilot would steer the boat.  Even if the linkage jammed, it would take a bit of work, but I think that I'd be able to disconnect the linkage between the wheel arm and the rudder post, giving sole control to the autopilot.

However, in the end I decided to have an emergency tiller made as a matter of "duty of care" because I would be very hard on myself if I lost the boat for lack of one.

So I spent several hours yesterday producing mechanical drawings to scale on graph paper.  The tiller will be tall, to the level of the cockpit rails so that I will be able to easily either lash the tiller or connect it to the Monitor control lines.  The tiller handle will face aft to achieve the 20" minimum length specified for the Monitor.  It will be supported 2/3 of the way up by a collar to be held in place by lines running from the aft corners of the cockpit to the forward winches on the opposite sides.  I expected the material to be mild steel but they suggested 1.5" diameter stainless steel.   Those drawings came in very handy at today's discussion with the welders.  They took the them away and will give me a quotation tomorrow. 

By amazing coincidence a distress call came in to the 8 AM session on VHF 22 from a boat 25 miles out that has lost both its autopilot and manual steering.  Then later in the morning David Miller told me how his spare tiller saved his bacon when he had a broken autopilot and the steering chain broke as he was leaving an anchorage with bad weather on the way.

In the morning I started work on mounting the new GPS on the binnacle.  I removed the faulty Trimble repeater then started to drill holes in the stainless steel support.  After drilling for 5 minutes and getting nowhere with the hard metal it dawned on me (Duh!) that I could use the four existing holes to mount a nice piece of teak upon which I could mount the GPS.  This would have the advantage of giving me a greater area of choice for positioning the unit.  I telephoned Reggie the carpenter and an hour later he was on board to discuss and basically design the piece.  He suggested improvements for both the positioning (i.e. make the board bigger to get the GPS antenna clear of the holding bar and better eye level) and mounting (i.e. use screws rather than thru bolts).  He hopes to have the finished piece, close to an inch thick and with all edges nicely rounded, tomorrow.

I plan to set up the GPS wiring in the morning.  The tricky part will be squeezing the 6-core cable through the fitting at the cockpit floor.  At minimum I must provide power to the GPS.  However, I'll take up Jak's advice and connect the NMEA wires to the VHF radio and its DSC capability. (DSC: "Digital Selective Calling".  At the push of a button the radio can send a distress call on Ch 70 in less than a second, that can include your location if the radio is connected to a GPS. http://www.boatus.com/husick/c_dsc.asp provides a readable description of DSC.)