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Welding

 

 

A welding professional once told me he could tell all he knew about welding in five minutes, but it would take a life-time to become proficient at the task. 

    However, with a few months of practice and a little professional guidance, you should be able to perfect your skill and be up to the task at hand.  The concept of welding is easily understand.   We melt the edges of two pieces of metal and fill the gap with a third the material from the welding rod.  What takes place within the melted puddle of metal is the key.  Only the metal which is mixed together within the puddle has been welded.   Also a molecular change is taking place within the puddle. The flux and added metal of the welding rod control this process. 

    In mig welding with hard wire, the shielding gas mixture and wire type control the molecular change.   Thus the importance of choosing the right welding rod/wire and gas combination for the job at hand.   Choose the wrong welding rod or gas and wire combination, and the weld either becomes too hard, too soft, or too brittle, and can be torn apart by the twisting and flexing of the hull in heavy weather.

    As for perfecting your skill: learning to set the right heat range on the welder is half the battle. Information regarding beginning heat settings is supplied with the rod/wire literature.   You fine tune this setting by what is taking place within the puddle.   In this area, a little professional help will go a long way in perfecting your skills.   Welding equipment suppliers usually can provide some of the guidance you'll need.

    Stick welding is traditionally  the excepted method of home boat building.   However, with advances in mig welding equipment for home use, mig welding with hard wire and/or duel shield will speed up the project.   Gas selection is especially important. A three-gas mixture ( argon 90%, co2 8%, oxygen 2%) works well.  The argon provides a controlled puddle environment.  The co2 adds carbon to the puddle, replacing the carbon which has burned off.  The oxygen aids in heat transfer to the puddle.

    In stick welding, E6010 is a general-purpose all position dc welding rod for 3/16 - 5/8 steel with light slag and good arc control.

    With hard wire (mig), spray transfer produces a slag-free weld. This allows the adding of multiple passes without the need of cleanup between each pass.   

    Dual shield is a flux-cored wire used in combination with a shielding gas. a thin layer of slag needs to be removed before adding an additional pass.

    Reference book: The Procedure Handbook of Arc Welding, by Lincoln Electric Company, Cleveland, Ohio.

This page was last updated on 05/10/14

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