Sunday, 26 March 2017

C&C 33ii Emergency Tiller Refinements

Ok, "refinement" might be a stretch.

C&C supplied a very nicely made alloy emergency tiller with the 33ii, and designed the boat so the top of the rudder post is easily accessed.   So, dealing with steering failure should be relatively simple - just slip the tiller over the post and till away.  Right?

Well, not exactly.    The cast aluminum tiller head's bore is a very snug fit on the stainless rudder post, and in my case, due to some very minor dings on the sharp edge of the bore, it was not possible to slip it over the post at all.   Even without those dings, once started, it was not possible to fully seat the tiller by hand pressure alone.   The tiller is secured by a stainless bolt that requires two 3/4" wrenches to tighten.  These were simply taped to the tiller.  (nothing to go wrong there!)    All things considered, not what one would want to be dealing with in an emergency.

So, I filed a chamfer on the edge of the bore itself, then sanded the bore smooth(er), and waxed it.  Hopefully it will slip more readily over the post.

I had intended to replace the machine bolt on the tiller hinge with some kind of shaft and hand knob arrangement to make it tool-less, but I got to thinking about it while some varnish was drying, and and I came up with a less elegant but workable approach.  Thinking about it, I'm not sure the hand knobs would have allowed enough force to secure the tiller, and while some kind of cam screw arrangement would probably be ideal, that was too far down this rabbit hole, even for me.  Besides, the varnish was nearly dry.  

An eye strap was riveted to the tiller head and a length of shock cord installed.  (using hog rings to make secure loops)  To this, a pair of tethered wrenches was ring-hitched.   The geometry involved and the tension from the shock cord combine to secure the wrenches, while permitting them to be withdrawn from the tiller if needed.  Ugly but functional.

Next iteration is to cut the open end off the wrenches, and bore holes for the tether.   This way the wrenches can be fully inserted in the tube.  

This proved to bed a minor lesson in metallurgy.   I cut the wrenches down with an abrasive-wheel chop saw, but drilling proved to be a challenge until I annealed the ends with a propane torch.  Easy then.  The holes were drilled, gently countersunk, and any burrs addressed with a conical bit in a Dremel.   The handles were dipped in primer, then paint.