14 September 2018
14 September 2018
14 September 2018
14 September 2018 | Adelaide, South Australia
14 September 2018 | Adelaide, South Australia

First experiments with the heating system.

21 May 2019
Matthew Dunk
So, I'm finally starting on the boat heating, though I probably should be writing an essay. But curiosity was getting the better of me and the pile of parts in the garage were calling.

So I have:

A Webasto Thermotop C, brand new from Ebay, around AU$1600 after customs and postage. The kit came with most of the bits I need, the fuel pump, various hoses, intake filter, exhaust and muffler etc.

50 meters of 3/8" copper pipe in a neat coil, about 250 mm diameter. (That coil was a bonus, saved me from coiling it which would have been tricky.)

So I fiddled around with the wiring harness after reading a few helpful posts online, and it turns out it is very easy to get the Webasto to run. When I finish the system I will document the final wiring setup, but in short it was a matter of removing a few redundant parts from the factory harness and putting an on/off switch on one circuit.

For the test I grabbed one of my big plastic tool chests. They hold about 80 litres of water so they are not too different to what I expect I will be able to fit in the boat, something around 50 litres.

I dropped the copper coil in the tub, after lashing it to some bits of old pipe to keep it reasonably well spaced between the coils. I attached the garden hose to the input end of the coil (the bottom) and attached some spare hose to the output side and ran that to a bucket.

I setup the Webasto to heat the water in the plastic tub, with the pickup down low and the return around mid height, but as it turns out the Webasto pump was pretty vigorous and had the water in the tub swirling around and self mixing, so it probably would not have mattered where the pickup and return were placed.

Then I fired up the furnace and let it warm the tub. I could have taken a note of the time taken to heat it up but there was not much point. For a start there is NO insulation on this tub, so the temperature curve was going to be pretty poorly once the water got much above the ambient temperature of 20 degrees C in the shed. Secondly, this was to be a test of the heat exchanger, which was the bit that had me nervous.

Note I said "had" me nervous.

It worked a treat. With the water in the tub at 52 degrees C (no particular reason to choose that temperature, I just finished my cup of tea and that was the temperature the tub had reached) and the furnace running, I turned on the garden tap and let the water flow through the copper pipe at a rate that felt right for a boat shower, which turned out to be 3 liters per minute when I measured it. The tap water was coming out at 19 degrees C.

Initially, of course, the stored water in the coil came out a 52 degrees like the tub, but after a few seconds, it settled down at 45 degrees and held steady. I let it run for a few minutes just to be sure.

So it does look like the rate of heat exchange with the copper coil is adequate for a shower, which was my big uncertainty with this design.

The plan is to run the buffer tank between 55C and 65C, so I expect hot water between 48 and 58 degrees continuous, or thereabouts, which is plenty hot enough for the kitchen and the shower, and possibly hot enough to think that fitting a tempering valve is a good idea, particularly with the problem of the initial higher temperature water pulse.

A windvane and the current autopilot.

14 September 2018
Manera came with an electric autopilot, called a Coursemaster.

It's getting old now, it's pretty reliable and well built. The drive motor and chain setup in the aft cabin look like they came off a bulldozer.

But the control circuit is getting problematic. Bad voltage drops when operating the drive motor, apparent from the display flickering. From time to time the voltage drop is enough to make the autopilot track erratically. I've gone over the whole circuit board looking for a dry solder joint, but I can't find it. So I have a work around. I've got a circuit sketched out that will leave the coursemaster operating either a pair of relays, or preferably, a pair of mosfets, with their own power supply, which will then control the drive motor. This will buy me some time with the coursemaster, but ideally I will replace the coursemaster with a design I have for a picaxe based autopilot. But that much can wait.

For now, I just have to get the relay/mosfet circuit built for the journey.

All going well, however, it won't matter whether the autopilot is working well or not because I am most of the way through building a windvane system.

I gave up trying to find a commercial version that would work the way I wanted on the Swanson. Most models operate directly on the boat's existing steering system and I felt like that would be difficult to implement as well as putting a lot of strain on an ageing system.

So I have built and auxiliary rudder system with a trim tab. There are a few advantages to this system if I can get it to work well. It does not add wear and tear to the existing rudder system, it does not need control lines from the windvane to the steering wheel (which can be a fiddle to get right) and it can serve as an emergency control system should the main steering fail.

I have based my design on a number of inputs, including Faye Marine's great page on design theory, a book on self steering for yachts by Gerard Dijkstra and observations of a similar commercial system called a Hydrovane. (The hydrovane gave me a sense of size, even though it is a different system, and I took on board the comments from a few hydrovane owners and made my system a good 25% larger.)

I have to finish building this vane, install it and test it before the journey. That's one of the bigger jobs.

The engine

14 September 2018
Manera has a surprisingly big engine for a boat of her size.

She has a 96HP Nissan truck engine. Most boats of Manera's size get by with less than 50HP.

Early on I got lots of comments that the engine seemed oversized. I started to worry about why such a big engine had been fitted.

Then I found out.

I managed to track down Manera's original owner (I bought Manera from the couple that bought her from him) and he told me a harrowing story of approaching a harbour after bad weather, when Manera had her original 65 HP Lyster diesel. Things went wrong and Manera ended up broaching (flat on her side). It could have been nasty, I think she may have even collided with the breakwater from memory, but she is built incredibly strong so it was probably the breakwater that felt it the most.

He felt, if he had more horespower, he could have avoided the problem, so fitted the Nissan.

Since then I have spoken to two other Swanson 42 owners who felt the same way. Both fitted 85 HP Ford engines to their boats and have been happier for it ever since. I have also spoken to two other Swanson 42 owners with smaller engines, 50 and 55 HP, and both said the boats were uncontrollable in strong winds under engine, and making way into headwinds was simply not an option.

I usually run the Nissan at about 30 HP, which gives me about 5 to 6 knots of boat speed, the engine sounds happy enough and I have motored this way for up to 12 hours at a stretch without problems.

So, I am happy with the engine, but it is getting old and I know sooner or later something will break that cannot be replaced and then I will be shopping around for a replacement.

Currently I am favouring one of the well built and reliable Toyota 4WD engines which are about the right size and have enough of a cult following here in Australia to make parts easy to obtain. I won't replace the engine until I have to but I do need to make sure it is good for the journey south, another task to attend to.

The rig

14 September 2018
Manera is a mast head cutter.

I have known this from the day I bought her.

Of course I didn't actually UNDERSTAND what that meant. I just knew it was true.

It took at least three years of sailing Manera to get my head around the logic of a masthead cutter. I am no sailing geek. I know there are lots of different rigs out there, I know the names of maybe half a dozen but I also know there are dozens more.

In short, Manera was designed at a time when big sails were difficult to handle. There were a number of solutions to this problem, one being to put two masts on the boat, each with smaller sails. (Some people have done this with Swanson 42s but the rumour is it did not work well. Only rumour, of course.)

One other solution was to put multiple smaller sails forward of the mast, and position the mast in such a way that this configuration left the boat balanced well with the sails in this configuration.

So Manera has a jib at the front which is an odd shape. It is a surprisingly small,very flattened triangle, reaching from the bow of the boat to the top of the mast, with the lines that control it attached way up in the air out of reach. This style of sail is referred to as a "yankee". Behind this sail, about two feet behind it, is a smaller, more conventionally shaped jib, that runs from deck level to a point two thirds of the way up the mast, called a staysail. The staysail has a leading edge (luff) exactly parallel with the leading edge of the yankee.

There's lots of technical guff around how these two sails work together. You'll find terms like "slot effect" bandied around a bit. And aspect ratios, and wind shadows... lots of words. But what matters to me is that, on Manera, they work WELL. It took me some time to find this out because Manera had been fitted with a bigger forward jib, called a "high cut reacher" when I bought her, which I had been using on its own. I had tried it with the staysail, and its big area would deflect air onto the staysail in such a way that the staysail would flop about and generally misbehave in all but very deep reaching conditions. I don't know what prompted me to pull out the as-yet untried yankee from its bag and try it with the staysail but I got a heck of a pleasant surprise. Suddenly the staysail was drawing nicely, the apparently small yankee seemed to drive the boat forward in a way that suggested it was much larger than it appeared, and the boat remained more upright for a given wind speed. The helm felt balanced and boat speeds went up by a good 20%.

I was hooked.

So I immediately went out and ordered a complete new set of sails, main, yankee and staysail, put the high cut reacher in a bag in the sail locker for emergencies, and have been sailing Manera as she was designed to be sailed ever since.

I mention all this now because there is one aspect of this configuration that needs to be attended to before the trip. The staysail stay terminates at a point two thirds of the way up the mast. When drawing hard, it puts a lot of strain on that point of the mast and creates a bend forward in the mast from that point. (That's ok, masts are designed to bend this much.) The bend would not be a problem except it messes with the shape of the mainsail and causes the staysail stay to go slack which messes with the shape of the staysail. The end result is a boat which sails like a slug.

There is a solution though. Manera has "running backstays". These are a pair of stays that meet at the mast at the same point as the staysail stay and counter this bending force by pulling backwards just as hard as the staysail pulls forwards. There are a pair of them because they can only be used one at a time, the downwind one always has to be left disconnected and out of the way because otherwise it would rub on the mainsail and destroy it, plus limit how far out the mainsail could swing. Not good.

So you connect the upwind backstay once you are moving and tension it up appropriately, currently using a set of blocks and a great big heavy lever called a "highfield". And this is the problem. The highfield levers are horribly heavy, and very dangerous if they become unrestrained in a seaway. Good friends had one come disconnected on the East Coast of Australia and it did a lot of damage to the boat before they were able to restrain it, and nearly did a lot of damage to them in the process.

Thankfully, modern ropes come to my rescue here. I will replace the current backstays with a type of rope called dyneema, which does not stretch, and replace the highfields with a special set of blocks that give me great purchase. If done correctly I will only have the weight of the blocks on the stays flopping around and with long enough tails, the stays can be slackened without needing to disconnect them completely and tether them forward of the deck house.

Another job to be done before the journey.

The decks

14 September 2018
Manera is a Swanson 42.

I knew nothing about Swanson boats when I first saw her. I was simply skipping through boat sales trying to find any sailing boats in my budget that had a reasonably clear deck.

I had been looking at the Adams 40 previously, but had removed it from list after visiting one at a local club. I found getting about on deck horribly awkward. A pity, because otherwise I think they are a superb boat.

Anyway, after about an hour of clicking through photos, I stumbled on a boat that looked like you could roller blade around the foredeck with ease. It was a Swanson 42, for sale in Sydney. Further inquiries about the design revealed that Swanson boats in general had a great reputation for build quality and seaworthiness, and the Swanson 42 was considered the pinnacle of the Swanson boat designs.

So I had found the make and model I wanted, all I had to do was find a good one. Which I did, three years later, in Melbourne.

So those decks really are incredible. You could, quite seriously, don a pair of roller blades and skate around with some degree of safety.

But her decks were tired. The fibreglass was lifting from the ply in a couple of places, and there were at least a dozen little niggly leaks that would reveal themselves when it rained. So the last few years have been spent strategically positioning saucepans and tupperware containers before I leave the boat after a sail.

I finally got started on the decks in February. I started with the aft deck because it was in the worst condition, and it was the smaller area. It was also the most difficult because, unlike the forward deck, I wanted to change its height to reinstate the toe rails that had been lost because the original deck was built too high. The job went well and the aft deck only needs a coat of anti skid deck paint now to be considered complete.

But the forward deck still needs to be replaced before this journey, so there's the biggest job.

A bit of electrical history

14 September 2018 | Adelaide, South Australia
Manera is basically a sound boat. I bought her in late 2012 in Melbourne, and was able to sail her back to Adelaide with the help of some good friends.

She was seaworthy enough to make light of the 500 mile journey, the only significant problem being that her battery bank was hopelessly under capacity, a problem that had been masked by the fact that during the two months of shakedown and preparation leading up to the journey, she had remained plugged in to the mains each night at the marina. Of course, 24 hours at sea and the state of the battery bank and the onboard charging systems revealed themselves as woefully disfunctional. No charge from the engine alternator, about 20 watts in total from the solar panels, the wind generator would put out power if the wind was right, but its regulator was the wrong sort for the battery chemistry so would happily declare the battery to be full and start dumping power into the dump load resistors as soon the batteries reached 50%. So we turned off the fridge and the autopilot and hand steered while eating Twisties most of the way home.

6 years later and she has been completely rewired from scratch. I pulled out everything, down to the last wire, and started again. It has been an unrushed process. I put the main items in place, switch boards and battery banks, then I started adding things ONLY if they were needed. Now she boasts 760 watts of solar, the 300 watt wind generator, and buck-boost charger to siphon power from the 24 volt engine bank in an emergency if the other two charging systems can not keep up. Then I left the wiring in a roughed-in state for two years, waiting to see if anything changed. It hasn't, so one of the first jobs for this trip is to transform the roughed-in wiring to something permanent.
Vessel Name: Manera
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