Set up question

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I have not posted yet but have been reading post for a few months. I have been doing some mig welding for nearly a year, and I am confused on one thing, right now. The "books" says to give ( for my setup- 250 amp lincoln mig, C25, .035 wire) 19 volts and 320- 360 ipm for a good weld. All the welders I work with may do 19-21 volts and around 250 ipm, that is using a cicular pattern. I thought the wire speed is like the current and you need a certain amount to get a good weld. I just want to be able to do a sound weld without going by ear on the setup, and having a good looking weld that may not hold. Thanks
Reply:I just looked through the Lincoln GMAW Guide, http://content.lincolnelectric.com/p...ture/c4200.pdfFor short arc transfer with .035" steel wire and 75/25 Ar/CO2, it shows a max wire feed speed of 250 ipm, 175 amps, 22 volts.It also shows that the transition current to go into spray transfer with .035" steel wire and 90/10 Ar/CO2 is 175 - 185 amps.Seems like somewhere above 250 ipm wfs with .035 steel and 75/25, you would be into a globular transfer mode.Just curious, have you actually measured your wire feed speed, maybe the dial setting or readout is not accurate?By the way, going by ear is not a bad thing, the sound of the MIG arc is a very good indicator of good or bad machine settings and weld quality.
Reply:Thanks for the linkI will measure the wire speed.It seems that once the wfs is over 250, it becomes difficult to get a nice looking weld, I guess the globular transfer would explain that.  Thanks Brett
Reply:Too high a wire feed speed will cause a crappy looking weld. Those charts are only a basic guide to a starting point. You adjust the settings for each individual machine as well as th thickness of the base metal. If those welders at work are guys who make their living laying beads then they probably have it right. The sound a mig machine makes when welding is a real good indicator as to whether everything is right or if something is wrong. Among all of the pros I know, including myself, the sound of the arc is the best indicator we have. Machines with voltmeters and ammeters are a relatively new thing. I used to use an incredibly expensive Miller setup, dual feed with a 1000 amp power supply. Voltage and wirespeed were both marked 1 - 10. The sound, arc and puddle were all you had to go on. With my Lincoln setup I am running .045 flux core at about 300 ipm at 19 -20 volts and about 200 amps. There is nothing to tell me the actual volts  and amps.The difference between art and craft is the quality of the workmanship. I am an artist.