heat, bead size etc.

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OK guys I'm learning as best as I can with practice, reading my welding book and practicing some more. Today I was out practicing with my new Smith econo. OA set on 1/8 mild steel. (Tip size MW205) Stitching 2 pieces of 1x1  angle together to form a T. I was really able to learn alot more about heat, working the puddle etc. One thing I  learned is that I'm moving way too fast with my MIG. I'm going to try slowing down, relaxing and allow the welder to do its job. I have a question regarding voltage and wire speed. My beads are somewhat narrow and tall (if that makes sense). Assuming my settings are correct if I slow down MY travel speed will the bead  penetrate more into the base metal and leave a somewhat shorter wider bead? What does voltage equate to and what does wire speed equate to as far as the look of the bead. Simple terms. Thanks snoboy
Reply:The voltage sets your penetration.  The wire speed is adjusted to match the voltage and wire diameter once you achieve proper penetration.  A thinner wire at high voltage will require a faster wire speed than a thick wire at the same voltage.  You set the wire speed by ear once the voltage is set.   You want that nice, fast crackling sound.  Too fast and you push the wire into the puddle and it pushes your torch away.  Too slow and the wire vaporizes far from the puddle and makes a lot of spatter.
Reply:Roger-that GMC. The more "stick time" I get the better I understand these bits of advice. Thanks
Reply:The electrode stick out (ESO), which is effectively how far away from the workpiece you are holding the torch tip, also affects the bead.Narrow and tall bead could be too much ESO, you are holding the torch tip too far away from the work.Also changing the gun orientation and whether you are using a push or a drag/pull technique on the torch affects the bead shape and the penetration.  Using a push will make the bead wider and flatter, using a drag/pull will make the bead taller and narrower.See here for some tips, diagrams and real pictures:  http://www.millerwelds.com/education...tips/MIG_tips/With a wire-feed welder, the wire speed effectively controls the amperage of the machine.  The voltage sets what amperage range(s) will work with a certain wire size and set-up.  Too much voltage increases spatter.And for 'household' welding, the nice "sizzling bacon" sound is what you want.  But for big industrial machines that have the ooomph, boosting the power may let you move out of the "short circuit transfer mode" and all the way up into "spray transfer mode".  The sound of the spray transfer mode is no longer the sizzling sound, but is more of a loud hissing sound.  To do spray transfer with 0.030 solid wire on mild steel, you need at least 150 amps and pure argon, 98Ar-2O2, or up to C15.  If you have more than about 15% CO2 in the gas mix, you can't get into spray transfer mode, you'll get into globular transfer mode instead.
Reply:Really good post MOONRISE!Some very good points on the various factors that affect MIG weld bead shape.  To reiterate and maybe add to some of your points:With the common constant voltage, MIG power supply, wire feed speed (wfs) determines the amperage.  Since amperage (current) is the number of electrons flowing through a wire or across the arc, you can think of faster wire feed speed as more electrons moving along with the wire.  Current is the primary factor affecting weld heat and penetration.The electrode stickout (ESO), or distance between the contact tip and the workpiece, directly affects the arc current also.  A longer stickout results in more resistance heating of the wire (I squared x r) and a colder weld because more current is lost to heating the wire and less current goes to the arc.The wfs and current must be balanced with the voltage, which controls arc length, the distance between the end of the wire and workpiece.  If the wire is stubbing violently into the workpiece and/or spatter is excessive, the voltage and arc length are to low/small.  And the opposite holds as well.  If the voltage is too high, the arc length is too long, the wire tends to form large globules, the arc power is very diffuse, and the weld may tend to be irregular with poor fusion and wetting at the toes.And as stated, torch angle affects the bead surface profile.  Particularly with pulsed spray and conventional spray arc welding, a push angle will flatten out the bead.