The MMAW electrode gets ‘red hot’ during welding and we end up with a lot of stub losses. How do we reduce stub losses?
The ‘red hotness’ is a sure sign of using too high a current and most probably much above the recommended current range for that particular electrode. Many fabricators in a bid to increase production use higher than the recommended current. This does not in any way increase the production rate and in fact hampers smooth production. Use of higher currents cause the following problems: • will cause burn throughs in thin sheets. • will cause large craters and over dilution with the base metal. This is not desirable as higher carbon or alloy pickup from the base metal may cause weld cracks. • the ‘red hotness’ may lead to loss of valuable alloying ingredients from the weld metal due to vapourisation. This will in all probability reduce the strength properties of the weld metal. • Will cause the slag to be ingrained and stick to the weld metal and prevent easy removal causing loss of production. • Loss of weld metal due to large stub ends loss.
