Only For Nutters – Part 17

“‘Tis the season for excuses, tra-la-la-la-laa…!” There are so many reasons not to be building the boat during the Christmas season it is remarkable that anything has been achieved at all. I have written before about the cold up at the workshop slowing everything down and making short days necessary just so I can get home to thaw out. The watery sun drops below the hills around 4pm and the temperature plummets. Time for a cup of tea and a mince pie!

But there is one inescapable, blindingly-obvious truth about boatbuilding: it doesn’t happen if you are not there! There is simply no substitute for putting in the hours. Of course one can work quickly or slowly depending on ability and inclination and standards of workmanship, but you have still got to be there.

Sorting out the clearances with a cardboard engine shape

To plan or not to plan?

I am never more aware of this than at the turn of the year, when I take down the old year planner with its blocked-out plans for doing this or that section at the right time, and the crossings-out of the things that didn’t quite get done. I put up the empty new planner with the delicious prospect of all the days of the year laid out, tempting me to start giving the new year some shape, and above all to work out how to get this project to a conclusion.

In some ways it is easy: just keep on working at all the jobs that need doing and sooner or later I will get to the end of the list. Then launch the boat! Simple, except that everyone (hoping to be able to fill in their new diaries with a party to look forward to) now asks “When will the boat be launched?” The lame response of “When it’s ready!” is not good enough anymore, as I have already declared this must be the final year of building and it is becoming increasingly apparent that the boat is getting to the stage when it looks like it might actually float.

But the project is so far adrift from the designer’s prediction of 1800 hours to complete that there must be something to learn from it. Undoubtedly anyone planning to build their own boat should take heed. The designer was very probably giving the number of hours an experienced team of professionals might take if they were working in perfectly temperature- and humidity-controlled conditions with all materials ready to hand and no deviations from the plans, no processes going wrong, no time for head-scratching or re-design. Our four years and 9000+ hours include lots of unpredictable variables, some of which have not been related to the project itself. No doubt temperature and humidity have played their part in slowing the process down, but so have available manpower, the re-design, the learning curve with its inevitable mistakes, the addition of lots of details not in the original plan, (e.g. building a mast, adding a big cabin-roof), and taking time off for Christmas. If I became depressed by the seeming lack of progress in the early stages, now I am resigned to its unevenness and less bothered about the finish date.

So I fill in the months and weeks on the wall planner with more hope than expectation and dream about a summer day, a large crane and some bottles of champagne! Which brings me back to the here and now – doing as much work as possible during the cold months so the summer launch becomes a reality. For once my intentions seem to be working out – must have been the planning! I reckoned on doing the interior during January and February, and here we are ready to roll. With some floodlights and a heater it should be fairly cosy, so on we go. There is a lot of cabinetry that has to be made, and that requires some vacuum-bagged panels, which means isolating a part of the workshop with bubblewrap curtains and laying up inside it. I have bought some more melamine-faced chipboard panels, lovely, clean and smooth. They give such a perfect surface finish and the vacuum bag pulls down onto them so well that I really enjoy this part. Of course it would be easier and quicker just to use plywood for all the interior stuff, but the extra work in making up the composite panels is justified by the considerable weight saving. I am not going to cut corners right at the end, even if it takes more time….

Engine pods

The sections I have been tackling just recently have been the engine pods. Another departure from the original plans, these are located under the cockpit and based on a picture of pods on a Wharram cat. In the raised position the 8HP outboards should fit neatly inside a cockpit seat clear of the water. When lowered, they should be well-protected against splashes by the pod shape. While building them I tried to keep in mind the forces involved. Most of this is compressive due to the thrust given by the outboards, so 9mm ply sides and some solid wood seemed appropriate. The fairing is less structural, so I used 3mm ply. Transoms for mounting the engines are 3 thicknesses of 9mm. The whole box is well-glassed to give structural integrity and the bearings are workshop-made epoxy and graphite. I find making these over an aluminium tube has been quite straightforward. The alloy is well-waxed before glassing. Heat-shrink tape squeezes the laminate tightly together as the heat accelerates the set. To get the bearing off after curing I blast the metal tube with the hot air gun until I can feel the heat coming through the resin and glass. Then I run cold water through the tube to cool it as quickly as possible. The greater shrinkage of the alloy helps to break it away from the resin and a little bashing with a hammer on the end of the tube usually does the rest.

Some of the design details for the pods have been challenging. I ended up making a full-sized cardboard template of an engine in order to be sure that it would tilt into the right position and the transom would be at the correct angle when the leg was correctly immersed. I also wanted to keep the fuel tanks close to the engines and reckoned on there being enough space within the pods to fit them in front of the engines. But it is not ideal for the tanks to be tilted and access would be tricky, so they needed to be mounted separately. The solution I hit upon was to construct glass boxes to be fitted to the underside of the cockpit floor, accessible from the cockpit through a hinged lid. In the raised position the pod will fit neatly around the box, and when lowered there is additional splash protection for the outboard head.

Some form of positive lock is needed for the pod’s lowered position. Ideally this will triangulate the pod to hold it rigidly to the boat so that drive will be efficiently transferred. The arrangement on my previous boat was a home-made parallelogram constructed from 2” angle alloy, that worked fine in forward gear, but in reverse the engine bounced around and was less than efficient because there was nothing holding the frame down. It certainly alarmed any onlookers! This time, in addition to the block and tackle to raise and lower the pods as before, I shall install a bar that will slip into a couple of slots when the pod is fully down. It will be tensioned with some bungee to encourage it to engage. There will be another slot at the fully raised position. Of course this means that someone will need to reach down to disengage the bar with one hand, or perhaps a piece of rope can be cunningly rigged to achieve this.

Fuel tank lockers just after releasing from mould.

Engine mounting issues

The original plans showed a simple ladder-type arrangement mounted on the back of the aft beam. There are several problems with this: how to prevent the outboard being doused in sea-water without having a permanently-lowered fairing (or an ultra-ultra-ultra-long leg); how to tilt the leg while still keeping the engine close to the beam; and how to prevent the whole arrangement from fouling the tiller bar. I could not make this work on my model (using straws and pins), so opted for the underslung pods. One big plus is that the weight of the engines is brought much further forward away from the ends of the boat. About 100kg shifted forward by a whole metre. The engine heads will be accessible by simply removing the cockpit seat above them. Still to be fixed is the location of the engine controls. This will be partly determined by the runs for the connecting cables, and is likely to be somewhere on the back of the main cabin bulkhead.

Another item that has to avoid clashing with the tiller arms is the Duogen. It is mounted on a C-shaped swivel support, and I had decided that the back beam was the right place for it. I taped a tiller and bar temporarily in position and worked out the stand-off required. In the end it seemed easiest to construct a box, which doubles as liferaft storage. The Duogen will hinge off the back of this. The box is accessible from top or bottom just by undoing or cutting some lashings, in case it becomes necessary to release the liferaft with the boat inverted. (Plan for the worst, but hope for the best! It is important to give detailed consideration to preparations for an emergency in order to make it more survivable.)

The mainsail was delivered in December – I left it up to the sailmakers to fit my job in where convenient, so as to get it at the most advantageous price. It looks so good, and so enormous! It is also comforting to think that I have now bought almost all the things necessary to finish the boat and make it go. I did not want to leave the sail until last, and perhaps be forced to save money on it, thus compromising the most important part of the boat. I would rather have a decent sail and no electronics onboard.

A little winter job that doesn’t involve thermal underwear or personal discomfort is sorting out the moment calculations. It would be so embarrassing to launch the boat only to find the bow or stern pointing ridiculously up in the air. The professionals weigh absolutely everything that goes into the construction and its distance from a known point, but I have taken some guesses particularly with the structure, on the grounds that e.g. the skin of the boat is pretty much evenly distributed. Now that I am doing the interior joinery it is important that I should know where the water tanks and batteries are going, and this has to be decided with reference to the expected centre of gravity. So far it seems that things are very close (within about 60mm) to what I was aiming for, and the total weight looks near to the target 2.5 tonnes. Grouping heavy items towards the centre reduces their effect considerably, as well as minimising pitching and hobby-horsing. Doing the spreadsheet also gives an opportunity to see the effect that stowing a lot of stuff in a bow might have. I have included many items, such as anchors, chain, tools, food, tender and outboard, and even 4 crew standing in the cockpit, that would not be included in the unladen weight of the boat, because I do not know of any boat that sails without them, and they do need to be accounted for. It is reassuring that the all-up weight looks like it will not be excessive. There are, sadly, tales of boats where a little extra ‘beefing-up’ here and there has led to a finished craft so overweight that it could not hope to perform to the expected levels. A heavier cruising boat puts greater strain on the structure and has less ability to carry crew equipment.

OK, festivities over! Back to the cold workshop! No rest for the nutters!