Tag Archives: battery

Bouncy battery box

When I bought Tammy Norie in 2013 she had no battery. There was a wooden frame for a motorbike-sized battery in the cockpit locker.

IMGA0759 - Version 2

I really wanted a larger battery — at least 70Ah — and Dad and I first put it here, in the engine locker.


It didn’t take much sailing to reveal what a bad idea this was. The engine locker is wet, and in heavy weather I noticed how much salt water was splashing around.  I particularly remember accidentally pouring water that had accumulated in the locker lid on to the battery during my first time out in rough water (see Against the Weather). It wasn’t long after that I realized there was a very snug location for the battery inside the boat: under the cockpit.


It didn’t take long to fix this up, and Tammy’s battery has been snug and dry every since. However, if you study this photo you’ll see that things are definitely not ideal, especially if Tammy were knocked down or rolled over.


The battery box, although snug, was essentially just sitting in the locker, on a slight slope, held in place by a block resting on the cockpit drain seacocks. It became one of those things that you must sort out “later”. I’m ashamed to say I’ve only really fixed the problem this year!

What mostly held me back was the idea that I’d need to build some sort of enclosing frame for the battery. For example, here’s the battery mounting (again, in the cockpit locker) from Sinobee:


Chris Boxer’s Emmelène also has a fine battery frame below the companionway. I’m sure I’ve taken photographs of it too, and will link them here if I find them! The thought of wood- and glasswork in the small space beneath the cockpit definitely held me back.

Over time I’ve become more and more interested in solving problems with “soft” solutions: more lashings and ropes and less rigid stuff. I realized earlier this year that I could just lash the battery in place. So I went to the chandler and bought a couple of small dinghy cleats, and and a length of shock cord and made this:


And yes, the battery is standing on rubber doorstops. I happened to have a few of these because I hoped that they might work as mast wedges, but unfortunately they’re much too weedy and hollow. I was very pleased to find a use for them.

This isn’t the end of the story though.

Firstly, for the curious, here’s what else goes in the volume under the cockpit in Tammy Norie. Forward of the battery go parts and spares. These live in watertight containers that I’ve (mostly) labelled clearly using masking tape and a big marker pen. It helps me find them in tricky circumstances. With this “system” you can swiftly yank out one box and the others tend to fall down surprisingly tidily.


Forward of the parts and spares go the tools, in water-resistant bags. Tammy Norie is a floating workshop and I have a lot of tools. One day I’ll write a very long and boring post about them all.


And then finally, forward of the tools goes the removable door with the companionway step.


Now, as part of the unsinkability plan I’m lining the boat with closed-cell foam. Here’s a sample 1m×1m×30mm of foam that I ordered from Lux Distribution.


It was quite a simple matter to mount the battery in a foam compartment. Here’s the place before I started.


I have to say at this point that these pictures look bright because my camera has an efficient flash. In reality, the area under the cockpit has no light, and most of this work was done with a head torch. Also, this space is 30cm wide and 25cm tall!  I have to get to it by shuffling forwards on my belly like a worm, with my arms above my head like Superman. There isn’t enough space to bend your arms once you’re in!

Anyway, the job was remarkably easy. Having measured the areas, I laid them out on the paper backing of the foam and cut it with scissors.  I cut a bit out of the aft foam for the bilge pump pipe (like Superman, remember). I did not, at this stage, peel off the backing and stick the foam to the boat, and I may never do so for this job: the foam isn’t going anywhere and I want to get to the bulkhead for inspection and maintenance.

Here’s how it turned out.


It was then a simple matter to put the battery in the foam. I say simple, but in fact it involves wiggling into the area like a worm, arms forward like Superman, while lifting a 20kg block of lead and acid over the seacocks. And then you discover that the nice slippery plastic surface of the battery actually has very high friction with the foam, and you have to shoehorn it into place using an HDPE chopping board.


Once that was done I could withdraw the board and tidy things up. Here’s the battery finally in place and reconnected.


This is a very “soft” solution.  The battery wobbles like a stiff jelly if you poke it. It’s being hugged in a gentle but firm manner by the foam and the shock cord.  I’m very confident that it will stay put and working even if the sea picks up Tammy and gives her a good shake!

This was also a great opportunity to experiment with the foam. This foam is going to make up the bulk of the floatation I’m planning for unsinkability. I’m hoping to get most of that done this winter. Watch this space!


Filed under battery, Repairs and Modifications

Maximum power

I’ve been having some difficulty with my battery slowly running down over time, in spite of installing a second solar panel. I’d been advised to install a maximum power point tracking (MPPT) charge controller.

Solar panels don’t produce consistent power at all voltages. If you connect them directly to your battery their voltage is pulled down to around 12V, but many produce more power at around 20V. In fact, the ideal voltage varies with the light conditions.

An MPPT controller has a voltage converter to allow the panels to stay at a higher voltage, and it has a processor that adjusts that voltage to track the maximum power point.

But beware, many Chinese suppliers are sticking the letters MPPT on everything to get sales. Some controllers have even changed from being MPPT to not because manufacturers have economized on components. This is all fraudulent, of course, but hard to police.

YouTubers to the rescue. Amateur enthusiasts on YouTube like to review gadgets, and these helpful videos by Adam Welch reviewed a low cost controller.

I now have one of these installed on Tammy Norie and it appears to be doing the job nicely. I’ve been able to connect my two panels in series rather than parallel so that they’re producing over 12V even in quite low light. The controller seems to hold the combined voltage at about 48V in sunlight, suggesting that my NASA panels have a maximum power point around 24V.


I haven’t been able to get an accurate current measurement. My meter seems to upset the controller, which may indicate that it’s doing something quite delicate. Time will tell if this scheme works well and I will report back.

In the meantime, this is the eBay listing I used. Worth a try for £25 I thought.

Update 2017-09-19: So far this is not working very well and I don’t suggest buying this until until I’ve had a chance to do more experiments.

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Filed under battery, electrics

Little jobs roundup, 2017-08

I usually make posts about big things I’ve done, and not many about the hundreds of little jobs I do on Tammy Norie. I thought I’d start a series of occasional posts noting these, and if anyone wants more details they can ask in the comments.

The 30-year-old mushroom vent over the heads compartment cracked. The plastic looked like old ceramic. Replaced, although I don’t much like the quality of the new one. I’ll keep a look out for a stronger replacement.



I bought a CTek battery charger before going to the Netherlands in 2015. When I got there, it didn’t work! What’s more, when I tried to return it to the shop, they’d closed down, and their parent company had gone bankrupt. CTek eventually agreed to send me a new one directly, but it has been in its box for two years, untested. In a rare stay at a marina, I decided to test and install it.


Here it is installed below the main electrical panel in what would be the engine compartment on a bigger boat. Below it you can see the gas alarm (below head level when sleeping) and a big circuit breaker. The solar panel regulator promises to prevent overloads, and the every switch on the panel has a circuit breaker too, so I’m pretty well protected from shorts. I have a better main breaker for the panel when I re-make it.


At the back of the compartment you can see water-tight plastic boxes with spares and parts inside. I label them using tape and a big marker pen, so that I can pull out the right box from deep in the compartment.

I shortened the plastic tube I put around my yard parrel to prevent chafe. I can now peak up a few more degrees.


I finally stuck down my second solar panel. It’s been attached with duct tape for the past year. In spite of that, it’s never tried to escape overboard. I only really need a second panel because I installed a fancy main radio with GPS and AIS alarms, so I that I could sleep more soundly on offshore passages. I don’t use this radio much inshore.


I fixed yet another leak. This one was through the bolts fixing the pushpit rail foot. This was a good test for butyl tape, which I’m favouring over Sikaflex these days. It’s as easy to handle as Blu-tack and seems very effective.


Tammy Norie’s bilge is too small to fit a proper electric bilge pump. I bought a very cheap submersible Chinese pump from eBay, connected it to some narrow hose, and ran that alongside the main hose, then through an existing hole and into the engine well.



This pump is not going to save any lives. It takes a few minutes to empty even Tammy’s tiny bilge, but it’s nice to be able to press a button. And the installation interferes with nothing else.

My old tiller pilot got wet inside, corroded, and stopped working. I sold the remains at a boat jumble. My uncle then gave me an old one he had in the attic. The same model. Great, except that it didn’t come with the mounting bar. Dad suggested the thread on the mounting socket might be a pipe thread. He was right! It’s a 20mm thread as used on 15mm copper pipe fittings. A quick visit to a hardware shop and I have a new mount.


The mast hinge sleeve has a habit of walking around the mast until it jams up. At one stage, I had to use a mallet to free it up so that I could lower the mast. So I’ve drilled and tapped a screw hole to keep it in place.


This revealed a probem further up the sleeve. There were some quite deep gouges in the aluminium near the boom.


The culprit? Countersunk screw heads sticking up from the strip of material on the boom designed to prevent chafing the mast! Fail.


I’ve tightened up these screws on all the strips, and increased the depth of the recess in some cases. It might be better to use some other kind of fixing. If you look carefully at this picture you can see that the screws at the end have been pulled inwards, as if the mast strip has shrunk, or the boom has grown.


The rivets holding the handle to my Captain Currey rigging knife came apart, and the handle fell off. So I replaced them with nice machine screws in new recesses, oiled the handle, and sharpened the blade on my stone too.


Lastly, I’ve been gradually working my way around the woodwork, rubbing off the old brown paint and some of the UV damage, then treating the wood with oil. You can see the contrast here. Imagine when it’s all done!


I’ve done the same to the tiller, but unfortunately I discovered that under the paint the tiller is not a very beautiful piece of wood. So that will be getting some new paint, and perhaps I’ll get hold of a bit of hardwood and whittle a new tiller on passage.

That’s all for now. I hope you enjoyed seeing the small ways in which Tammy is improving.

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Filed under Repairs and Modifications