Thursday, 3 December 2020

More Improvements During Winter Lay Up

 In my previous post I stated my forlorn hope that there may still be a chance of a few days sailing on Lake Windermere before the onset of winter! Sadly the weather continued to deteriorate throughout the autumn thwarting the possibility of another launch. During this laid up period, I have taken the opportunity of continuing to address the logged list of observations and problems that require attention. 

Whilst cruising the West Coast of Scotland, I noticed that when the boat rolled in a swell, the centre plate could be heard knocking against the sides of the centre board case which, also proved to be particularly annoying when moored. I was a little surprised and concerned that this was occurring and came to the conclusion that this may be an anomaly to the intended design characteristics.  I mulled over the problem for a considerable amount of time until I finally arrived at what I thought may be a potential conclusion. 

The 25 mm thick stainless steel centre plate has an anchor/pivot hole bored to provide a reasonable amount of clearance for the 20 mm diameter pin which, is housed in fibre epoxy bearings set in the sides of the upper part of the centre board case. The designed width of the case is determined by laminating two sheets of 15 mm plywood which form an integral part of the boat’s backbone. This thickness of plywood was not available in the UK, I therefore had to use18 mm the nearest thickness available, its use effectively increased the internal width of the case by 6 mm. It was my suspicion that therein lay the problem. 

My solution was to cut two pieces of 3 mm thick fibre reinforced sheet rubber to the exact profile of the upper part of the centre plate, these would then sit either side of the plate acting like two large spacer washers. Fitting proved to be a relatively straight forward job. Firstly in its horizontal position, I located the plate’s centre of gravity, I then provided in situ support with a jack before stabilising its position within the confines of the case with wooden wedges. During the build I had the foresight to fit stainless steel screw bungs either side of the pivot bearings to enable removal and maintenance. Following the pivot pin removal it was a straight forward manoeuvre of feeding in the rubber sheets from below, re insertion of the pin held the rubber spacers in position. 

Since the boat has now had its first season of use, carrying out this operation also provided me with the valuable opportunity of inspecting both the pin and the epoxy bearings, all were found to be in excellent condition showing no apparent signs of wear to any of the surfaces. Since the purchase of the plans I had always considered this area to be a potentially weak point in what overall is a great design, I had therefore made it my priority to undertake this inspection. The results have reassured my confidence in both the design and its construction. I was particularly pleased that the epoxy bearings showed no signs of stress or wear, I undertook their design and construction following consultation with Francois, primarily because I expressed my concern that the pin bearing surfaces being only in plywood might wear more rapidly, possibly allowing the ingress of water into the structure.


The sheet rubber spacers have been cut so as not to project
 below the level of the keel/centre board case.

During my voyages off the Scottish coast, I moored Bunty B at several marinas and as you might expect the pontoon heights varied considerably. On occasion I encountered the problem of having the all-important mid-ships fender tie in point, insufficient in height to allow the fender to protect the rubbing strip, on one occasion I even resorted to tying off a fender through the centre of the shroud turnbuckle which proved to be less than ideal, particularly due to the restricted amount of room in which to thread the line and tie a hitch. I pondered over this problem for some time, trying to source a method of fixing some sort of clamp to the wire shrouds, all it seemed to no avail, until eventually I solved the problem with a simple solution. I purchased two 8 mm bow shackles and ground out the inner clearance to enable them to pass over the turnbuckle jaws, I then simply discarded the clevis pins attaching the shrouds to the turnbuckles and attached the bow shackles passing the pin through the whole assembly.



The adapted bow shackles provide fixing for the shrouds
and a useful fender attachment point.

The cabin shelves above the quarter berths are well designed and indispensable, their usefulness knows no bounds, attracting a multitude of essential’s from smaller items through to books and binoculars, the downside is at times you can’t find the smaller items buried beneath the larger! Furthermore a rough passage distributes the overflowing contents across the cabin floor, more storage space is of the essence. 

Whilst sat in the boat contemplating this conundrum, I noticed that there’s a free void within the cabin where your head very rarely ventures, up under the coach roof aft against the companionway bulkhead. I therefore designed and constructed two small lockers, port and starboard, closed off with drop down doors. This proved to be a tricky little project owing to the geometry of the space. The finished result is both aesthetically appealing and provides a small but additional storage space which is nonetheless at a premium on such a small boat.