Something to do on a rainy afternoon

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A while back i posted a coupon of a T fillet, the opinion was that the bead is cold not having flowed out, however the back side shows deep penetration, meaning lots of heat, very contradictory. Enough heat to melt through should also have the bead flow and not be lumpy. Getting back to basics, i carefully measured the voltage from the contact tip to the work clamp and the current.The chart under the cover is where i started the evaluation, 1/8 in. stock with 0.030 wire is where i set the controls to.I increased the heat [voltage] a half step at a time keeping the wire speed constant and rated the fillet, recording the voltage, current, wire speed and heat control settings. The recommended settings produced a low end result with the bead somewhat crowned and some sign of penetration, correct leg length and rough inconsistent stack of dimes. Increasing the heat a half step improved the bead quality, more uniform stack of dimes, less crown. I continued the process until the arc became too hot and unstable. Next i did the same varying the wire speed with the voltage constant.Comparing the data to the recommended values set by the wire manufacture, Hobart, the voltage range 14-16 matches what i recorded. The optimum voltage, 15.3 @ 132 amps yields the best formed bead, slight crown, Tig like stack of dimes with deep penetration. I purposely stopped the arc without allowing the bead to fill the creator at the end to see what the last puddle looks like. The last puddle is shaped like a large grain of rice indicating that the base stock in the direction of travel is melting at the seam deeply into the stock.  I repeated the tests for 1/8, 3/16, 1/4, 5/16 and 3/8 inch stock with 0.030, 0.035 and 0.045 wire without any joint prep.Conclusion:The chart in the unit is a good starting point for heat and current, all the optimum settings were the recommended values + a half more; i.e., heat is 5, use 5.5. The 0.001 amp rule is also a good starting point.If you have access to the wire manufactures data for the volts, amps, wire speed so much the better to help tune-in.The data from this round of testing is only for a filet weld without any joint preparation and will need to be tuned for other welding conditions, but still a good starting point. I don’t know how i lost sight of the basics, focusing on current and penetration too much.Make and keep notes of the best settings.You also need extra eyes and hands to keep track of what’s going on at the arc and read meters. http://www.millerwelds.com/resources/calculators/