Mark One electric drive throttle

We went down to King Malu to try to get the throttle working. No it wasn't necessary, but I will sleep more peacefully knowing that the new motor is controllable!

It's amazing what you can make out of an expired MEA Elite Club membership card, a couple of gear wheels from a remote control model car, some 5mm threaded rod and a small piece of wood.

The first attempt was a failure. The voltages we were getting were strange and unpredictable. That was till I realised they had sold us a logarithmic rather than linear potentiometer.

Replacing it with the linear pot we got the following voltages:


Forward max throttle is 4.38 volts
'Neutral' centre throttle is 2.7 volts
Reverse max throttle is 0.8 volts

The central 'neutral' position is slightly variable between 2.7 and 2.85 due to mechanical movement in the morse lever. There is a little play in the rig we attached to the morse control but most actually comes from the chain linkage down from the morse lever.

We will rebuild the mounting for the two gear wheels and potentiometer for the final version.

Paint, gear wheels and rolling wheels

I went down at 8:30 before work and put a second layer of the laquer paint on the for'ard cabin. It covered well, but not perfectly, was a pain because the hairs kept coming out of the brush. I think we might have hair problems because the cleaning solvent 'melts' the glue holding the hairs in the brush... not sure, but when it happens it's a total pain!

Anyway, I now think we have done all the painting for this year. The cabins are serviceable, albeit not luxury. Next lift out we'll do some concentrated work on upgrading the cabins.

At lunch time we went looking for some gear wheels. We need to attach a 2:1 ratio gear set to the morse control to work the potentiometer for the electric drive. Tim had a brainwave over night - remote control model car gear wheels. We went to the specialist remote control model shop in Larnaca and found exactly what we need. I'm not sure the shop owner really understood us, partly because of his English and our lack of Greek and partly because we are not building a remote control model car, but a full size yacht!

On the way home from work we put some new chunky wheels on the gangplank. Although the wheels looked great, one had already broken. We'll see how these fare.

Painting the for'ard cabin

Well, the gangplank is now is use and much easier to get on and off King Malu. Whether it's good enough to be called a passerelle is another matter. Hmmm... in the photo it does look good.

We started this morning by tidying up and piling up the junk from the boat that was multiplying... or seemingly multiplying... around our house ready to take to the tip sometime this week. Obviously there is a load of parts of the old engine, but sadly there were spares for the old engine too. I think it won't even fit in one car load!

We then glued the new for'ard cabin/heads door. We are making it out of 2 layers of 5mm marine ply with an edge of 8mm marine ply between to make a gap and lighten the door. Cleo, one of our cats, is very investigative and kept following us around, keeping well clear of the wood glue while we spread it. Then I needed to cut another piece of wood and used the rotary saw for that. Cleo, flew across the room, straight over the wood glue, leaving footprints in the glue and sticky paws on herself. Sadly washing it off made her sick later in the day.

Down at King Malu we screwed in the final two cowls just in front of the main mast. These have cover plates so that we can remove them for day sailing and only use them when we are on longer passages. Both of the two heads have extractor fans in them, but neither of the two fans work! Another job for another day.

After lunch I painted the for'ard cabin. Originally I had intended just doing beside the beths which was pretty manky and gross green (if you could call it that) colour... the colour was close to that of fetid pondwater.  When I started I realised that I had to paint the ceiling too, since moving one of the lockers back to make a work surface had exposed some equally unsavoury ceiling panelling. Anyway, should look much better,  but more work than I hoped. Needs another coat sometime this week.

Meanwhile Tim cleaned up with the miracle cleaner ('pink stuff') the stern cabin ready for painting sometime in the near future. I couldn't face any more painting today and we are beginning to run short of internal marine paint.

After that we tried to fit the spotlight in the stern heads. There were two wires coming down inside the door post to bare ends where the switch should be. Easy... just attach a new wire, draw it through and wire it up. Tim, suggested soldering the new wire to the old. Being impetuous, I just twisted them together. Of course, it didn't work and the wires separated mid way inside the door post. So with the other wire I did get out the soldering iron and connected them together firmly. But... the wire wouldn't go through some of the tight bends at the top of the door frame.

Next we attached a piece of very light cord to one of the wires and drew that through. The intention was to use that to pull the new wires through. But... it separated from the wire with the wire half way down the inside of the door post. Somehow the door post had been split, so we then wedged a screwdriver in the split, splitting it wider, and foraged for the wire with a bent coat hanger. Bent coat hangers are one of the more useful tools invented. Amazing what you can do with them!

Eventually, wires through the door post (which will need gluing and clamping sometime this week to repair) and the spot light works.

Gangplank now in use

During the week we have been trying to make a cover for the inflatable dinghy. The reason for this is that the bottom of the dinghy is black and when its on the foredeck upside down it gets very hot due to the sun. So we decided to make one out of the 'spare' WeatherMax we had ordered. We made the plan and took it round to Sheila's on Thursday, as you can read in the blog, that was not entirely successful.

This morning we started at 8:30 with the sewing machine we inherited with the yacht. We managed to get two seams attaching tape to the the back of the cover, but then the machine was not happy stitching the ends of the tapes. We 'kind of' finished it and Tim went into the Singer shop on the way to King Malu to get some more needles and to ask about servicing the machine.

First job at King Malu was to attach wheels and the fixings to the boat for the gangplank. That went well and then we tried using some shock cord and the halyard from the mizzen sail to support it. Kind of worked, except the shock cord stretched too much.

Then Costas from Raymarine arrived and we discussed what we would do about navionics. The extra expense on the new motor means we don't really have funds this year for everything we might want... actually it might be a blessing in disguise: Raymarine have just released a new series of widescreen  chart plotters. These new chart-plotters use digital rather than analogue radomes. So, our current plans is to put in a cheaper chart-plotter this year and trade it in for a new digital radar/chart-plotter next year.

Then off to Comar to buy some parts to finish off the gangplank... well, not finish off, but get it serviceable for a while. We really want to have nice handholds along the gangplank but the cost of 25mm stainless tube here is ridiculous, so for the moment we have one with a rope linking to the boat. Serviceable, but not pretty.

Whack... or I should say WHACK... as I walked into the boom without noticing. Now have a bump on my forehead. Fortunately was wearing a leather hat which protected me somewhat. First time in 8 months. Not bad I suppose.

We glued the final piece of Treadmaster down: This is above the vents from the for'ard heads. We had thought about making a dorade/step combined, but seems too much work right now, so we have already bought too cowls and will mount them tomorrow.


Finally, we fitted the locker back in the for'ard cabin, leaving a work surface there, and allowing a lot more light into the for'ard cabin. The whole cabin feels much more open now.

'Pass the pink spray and some kitchen towel.'

Then final task before leaving was to clean all the surfaces that need painting in the for'ard cabin so that hopefully tomorrow we can put first coat of paint on them. Pink spray? I think it's actually called Miracle Cleaner. It seems to be a miracle cleaner on grease and oil and other much. No idea what it does to your lungs - there isn't a health warning on it, and one of the main ingredients is citric acid, which makes it smell nicely of lemons.

The ceiling panels cleaned up nicely at the same time. There is still scorching from the fire that the previous owner had in this cabin, but replacing the veneer for the surfaces is something will be postponed till 2011.

Talking of miracles, its amazing that King Malu still exists and that the previous owner is still alive. The scorching from the fire happened while the previous owner was sleeping in the stern cabin and a 12 volt fan in the for'ard cabin caught fire, filled the place with smoke and then put itself out. And no... the previous owner didn't have smoke detectors anywhere on board. But we will!

Controller for electric drive

One thing that has been bothering me for some time is how to interface our morse control lever with the new electric drive chain. Yesterday I was sent a diagram from  electro-vehicles.eu which helped a lot.

It appears that the engine throttle is controlled by a potentiometer across a 5 volt supply. There are two switches - one for forward and one for reverse.

OK, makes sense but how on earth do you do this on a yacht? A yacht morse controller moves forward to increase throttle and backwards to also increase throttle from a central null point.

For days I have been puzzling thinking of this and then suddenly, very late at night it came to me:

Use a DC:DC converter to create a negative 12 V from the positive 12 V and then use a dual gang potentiometer (attached to the existing Morse controller) so that the centre is 0V and with one track wired inverted. Moving one way will increase volts on one track and moving other way will increase volts on the other track, the diode mixer will mean moving either direction from the centre off will increase voltage to the output.

Only about 20% of the 270 degree track would be used in each direction due to the throw of the Morse controller. For protection, use a 5V zener to ensure it never goes over 5V and a 2 way switch (also attached to the existing Morse controller) to switch between forward and reverse. May need some fiddling of components to get voltages correct for the amount of travel of the potentiometer.

I slept peacefully after realising this and then in the morning woke and realised I could use two op-amps connected to the output of the potentiometer tacks to provide the forward and reverse connection.

But simpler still... when I read my email from Andrea at electro-vehicles.eu... they can program the controller to accept centre null and forward/reverse off the one control. They call this 'wig-wag' in motor vehicles... we call it morse control in yachts!

Making a cover for the inflatable dinghy

OK, it's late... frustrating evening trying to make a cover for the inflatable dinghy. Went to Sheila at 4pm, for her to sew it... and left later than we should without it complete. (Her sewing machine was playing up)

Tried to use the protestant sewing machine at our home (protestant = unorthodox) and failed. (The power cable is missing)

Then tried to get the one we inherited with King Malu going. Just about succeeded. Tomorrow or Friday we will finish it... I hope.

So does anyone know about servicing sewing machines?

Treadmaster complete

Looks great the Treadmaster doesn't it? We taped it together over night as we had found that the joints tend to pull appart if left untaped.

Looking at the dinghy we thought about the need for a cover. The black bottom when inverted gets very hot in the sun.

I'm writing this post 6 days later and I cannot for the life of me remember what else we did all day. But I do remember working the whole day on the boat. Days seem to merge into days when refitting a boat that hasn't been sailed for 8 years. There is so much to do to bring her up to standard.