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If the welds were brittle and fractured easily, most likely you were running way too cold - not enough heat, you were melting the rod onto the surface, but not melting the base metal and getting good admixture between the base metal and the weld metal. As others say, the process actually produces a "puddle" of molten metal at the tip of the rod, and this "puddle" consists of both base metal and weld metal. A starting rule of thumb is "one amp of current for each thou of rod". So, for example, a 3/32 rod (which is 0.9375" or 93.75 thousandths of an inch) would be looking for a current around about 90-100 amps. That's a starting point - only experience will tell you when a rod needs more heat or less. But the manufacturer of the rod will also publish data for it which will give you an excellent starting point. Current is controlled by more than just the switch on the box, it's also controlled by the length of the arc. The longer you hold the arc, the higher the current - the more heat, but also the more violent the action of metal transfer from the rod to the work. This leads to lots of splatter and a stringy and poorly-adhering weld bead. Practice drawing the rod slowly and evenly, and "feeding" it down to the joint as it is consumed, to maintain an even arc length. Most beginners draw the rod way too quickly along the joint, and also "stab" at the joint rather than smoothly adjusting position to compensate as the rod is consumed. You can teach yourself to stick-weld but it's hard. Much easier to find a skilled welder and get an hour of instruction, and follow up with a good book - I recommend "New Lessons in Arc Welding" published by Lincoln Electric at www.lincolnelectric.com. HTH GLWI llater, llamas
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