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Hi, Lori A few more things that can produce porosity are: moisture contaminated low hydrogen rods (7018 is the most common, but 7016, 7028, 8018, 9018, etc. are also low hydrogen rods.) These rods must be kept in a rod oven once they have been removed from the sealed container in which they were purchased. The beginning of a bead on cold metal will sometimes show a bit of porosity which the remainder of the bead, on hot metal, does not.
Also, lifting the rod straight up at the end of a bead will often cause a single, crater like hole, though this is not what you are describing. Dr. Sportster assumed you were asking about SMAW since buzz boxes have been the standard equipment for entry level welders, but maybe you are using wire feed. Prices on low powered and/or no name units have certainly put them within most people's reach. The most common cause of porosity with GMAW is inadequate shielding gas. Either the gas pressure is adjusted too low, the gas is being blown away by air movement (like wind or a fan), or there is a more complicated problem in the gas delivery part of the system. You can aim the wire feed gun at your bare hand, pull the trigger to feel the gas, and still have time to get your hand out of the way before the wire hits it. That's the real world way to find out if gas is coming out of the nozzle. I don't know what the OSHA approved way is. All the best, Stan
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