Tuesday, August 11, 2009

Frame built

Frame builtI've made a start on the frame on the port side.

At the bottom, you can see I've welded in a piece of angle iron to hold everything in place down there, without needing to worry about the wooden deck.

I did the welding of the angle iron using some of the low hydrogen welding rods left by the contractors. I had been told that using the rods was 'quite tough', as the flux tended to melt and flow over the electrode after stopping welding, making it hard to subsequently arc up again.

After some experimentation, I found that keeping a small flat file nearby, then cleaning the flux from the tip of the electrode before restarting welding was all it took to produce consistent, good welds using these rods.

Reading up on low hydrogen rods on the interwebs, I see that the whole idea of the rods is to keep moisture from getting into the welding process.

From what I can understand, relatively high levels of moisture in the welding rod yields a high hydrogen content in the weld, which in turn makes the weld weaker and susceptible to cracking.

As far as storage of my welding rods on Lady Jane, all the fancy low hydrogen rods count for nothing as I've just kept the rods in their open packets, lying in a crate in the stern compartment.

Apparently the first step in keeping the moisture content in welding rods low is to store them at high temperature after opening the packet. Obviously a problem for me here with no power on during the week, and very conscious of overall power consumption on board.

I've seen some disparaging remarks about the effectiveness of using a small box with a 100W light bulb in it. It seems that for the purist, only a special purpose oven kept permanently on will do.

I think there must be a better option - vacuum packaging the rods when not being used maybe, and only heating them just prior to use?

My personal view on all this is that none of welding I've done so far, or intend to do in the immediate future, is critical, so the storage of 'wet' rods is not really an issue. I may, though, think of a way of storing them better and heating my rods before/while using them in future. This seems like a reasonable compromise.

If I'm to do any welding that could be critical in future, I guess I'll have to consider buying smaller packs and simply opening a new packet of rods just for those jobs, then keep them heated while the job is on.

All interesting stuff to learn about though.

4 comments:

  1. Isn't that a hatch under your angle iron ?

    Bill Kelleher

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  2. Hi Tim, I asked David about your welding rods( he is a welder by trade) He says you can get away with using a 20 watt bulb in a small wooden box( the box should be about 1/2 inch bigger than the welding rod box)with a flap door on hinges to keep the heat in. The light should be on constantly as letting them get damp then reheating them later doesn't work, they are no good once they get damp. You don't need 100 watt, 20 will do, just need to keep some warmth so they stay dry. Hope that helps, good luck. Rhianna

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  3. Hi Bill

    It's not a hatch, but concrete from where some machinery used to be mounted on deck.

    Regards

    Tim

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  4. Hi Cyberangel

    Thanks for that, your contribution is very much appreciated.

    Tim

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