Sunday, 21 November 2010

I have the power

It seems like it was an age away now but back in the summer I bought the battery from an electric fork lift truck.
It was 48volt, made up from 24, 2 volt cells wired in series like this one

The steel box they were in was split and rusted and the first job I had was to cut the copper links joining them together and lift them out. Easier said than done as they weigh 28kg each and were packed in like sardines. When they were first installed in the box, they were dry, then the water was added. That weight of that water causes the casings to spread and makes it almost impossible to pull them out. Once out, they spread and the water level drops inside causing the lead plates to be exposed, so they cant be left in that state. I made a plywood box in the new sixe and shape needed to fit the space in the engine compartment where they will need to go.

So, I made up temporary handles from insulated wire, twisted round the two poles and lifted them very carefully using an electric hoist. They stand 28'' high and I couldnt lift them manually over the sides of the steel box. I cut off the remainder of the copper links, removed the auto top up tubes and drilled down into the top of each post to accept a threaded insert which has a 6mm thread inside.

For almost 4 months they have been patiently waiting for a new home, not quite dormant, occasionally belching and bubbling hydrogen gas as they slowly discharge. Getting them installed in the new configuration and back on charge has been the priority goal but ive had to delay untill the engine room was weatherproof.

By last monday, things were finally ready and I took them out of the ply box, took the box apart so I could fit it through the wheelhouse floor framework and put it back together. Then I started the painful task of carrying them out of the shed, into the wheelhouse and lowering them into the box.
Its bad enough having to do it once as they weigh almost three quarters of a ton, but once they were all in, I noticed the base of the box was sagging and there was nothing for it but to take them all out, strengthen it and replace them again.
It was an all day job and when it was done, so was I.

It agrevated an old back injury and I needed two days off to recover.
I bought a length of copper bar, 5mm x 19mm, measured the distances between the poles, drilled holes and cut to length to make the links which go between the cells so I can make up 4 strings of 12v batteries comprising of 6 cells each.

Today ive bolted all the links up and sealed round the tops of all the cells to prevent overspill of water from the cell tops. This is what caused all the corrosion and mess in the old steel box, and I certainly dont want acid swilling around the engine room bilges.
Nest step is to get them on charge.


  1. You are impressive Amy!!! I was down working on my already completed boat and didn't get nearly as much done. I'm just replacing the counter tops, varnishing the sole, and rebedding a port light.

  2. I think obsessive, compulsive and sad is a better description Charlie.
    To some its a hobby, to most its a project but to me its all ive got in my boring life.
    Ive swapped a social life for a pile of scrap steel and an empty bank account.

  3. Amy OCD seems like the only way to get anything done is this life. You can either work 40 hours a week and spend your two weeks of vacation pissed (English definition) or you can be OC and make your dreams come true. I have a hard time making small talk about things that just don't matter.

  4. Your right. Ive seen some peoples projects drag on for years, sometimes beyond careers, marriages, families, house moves etc, and still not in a position to set sail. By the time the boat sees anything more than rain water, its obselete, its systems only fit for a museum.
    People accept this as normal. I cannot.
    I throw myself in and make it my obsession.
    What bugs me is the way people tell me im wrong and doing too much too fast too soon.

  5. Amy this is a signature that I have on another forum. It really rings true, "Money is not the only thing one has to spend; the other thing is life. The difference is that you never know how much is in the bank, or what your balance is. Your life is your inheritance. As soon as you realize this, you start trying to spend your life wisely." - From "Advice to the Sealorn" by Herb Payson. You can't know how much longer you will have to live so make sure that you are working towards what you want to do. That is how I read it and that is what you seem to be doing. Carry on my friend. Carry on!

  6. Have you charged it yet? Now you can keep a mini fridge on the work site!

  7. Amy, I remember reading on your blog somewhere you were putting in some cat5 cable.

    What are you going to use that for. If I remember right it was going out side.

    BTW put a search app on your blog please.


  8. Fred, with minus 10c temps inside and out, a mini fridge isnt realy needed at the moment.

    Kevin, I used a 10mt cat5e from Maplins. Unlike a USB, cat5 doesnt need boosting when running over 5 mts as its a low loss cable.
    Its going to run up inside the mast and plug into the USB connector of the wifi dongle, all wrapped in a plastic bag, and the dongle will be mounted on a sat dish

  9. Hi Amy,

    I came across this boat building blog... close to home?


  10. Hi Conall
    That blog is none other than Kevins, see three posts above this one.
    We are at similar stages at the moment.

  11. A little, its been a misserable month weatherwise. I did write a massive update and the useless 3 wifi dropped the signal and Ive not had the enthusiasm to have another go. Grrr

  12. I know how that goes. Thanks for the update and Merry Christmas!!!