How can I get better MIG starts?

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I'm working on a machine that I've never used before, so I can't attest to how it was on it's maiden voyage or anything.  Almost every time you pull the trigger, you get a loud "pop pop pop pop pop" and then sizzle.  I wouldn't mind so much, except that it's blowing random pieces of wire onto the metal along with the typical spatter.  I don't feel the gun kicking at all.  Once it gets going, it settles right down and welds fine.  Still a little more spatter than I would prefer, but I wouldn't be surprised if that isn't just my inexperience setting a machine like this.  I'd love to get the spatter free welds that I see some of you post on here, but that won't be happening this week I'm sure.Background on me:I've welded for years, but I don't do a ton of MIG.  I do mostly TIG and stick with a Thermal Arc Fabricator 186 (previously a 185).  I own a Hobart Handler 140 that's full of 0.023 and C25 for small stuff.  The only other MIG machine I've used is my Millermatic 180 with auto set.  I've read hundreds of posts on this forum, but never registered until now.Machine I'm on now:Miller CP-200 Power SupplyS-52E Wire feeder75/25 gas with 1200 psi left in the tank, 20cfm with a real flow gauge (pulled from a previous machine w/o this problem)0.035 Lincoln L-56 (ER70S-6)Bernard 300 amp Q gun, centerfire consumables, all brand new.Expecting a bad ground, I've wire brushed every connection from the teeth on the ground clamp up to the two outputs on the stabilizer inside the machine.  Cut off the end of the wire that was in the ground clamp, brushed out the hole it went into, and reassembled with a clean wire end.  I always grind the metal clean, both where I weld and ground (TIG habits).  I also always clip the wire perpendicularly before starting with a pair of MIG pliers.  I've tried switching stabilizer connections for my ground, and neither fixes the problem.I did notice that the drive rollers are the wrong size (0.030).  That's being replaced, but it'll be a week or better before they get here.  In the mean time, the feeder has no problem pushing the wire into a piece of wood without stalling.  It'll just curl and keep on pushing.  It doesn't even take a whole lot of tension to get that positive of a push.  I tried doing a series of tack welds to see if it would sputter on all of them, and it didn't.  Only the first sputters, and all the rest are good clean starts.  Because it does this, I would think the rollers are not my issue, but who knows.  Could be shielding gas coverage, but I've forgotten to turn the tank on before, and don't remember ever having so much sputtering.If anybody has a similar setup, could you recommend a decent starting point for 3/16" or so steel?  I've been around 47 on the wire feed ("50" puts out ~363 ipm according to my 6 second measurement) and 19 volts (actual, not scale).So, I'm lost here.  What else can I do to get better starts?  Or, is this what I should expect from this machine?
Reply:I would turn voltage to about 20 and wire speed around 290- 300 IPM. Also might want to see if there is a burnback adjustment. It sounds like you may have too much wire stickout to get a good start. Try clipping the wire close and see if that helps your starts. If that helps you would want to gradually increase burnback.Miller xmt304,  Miller S22 p12, Miier Maxstar SD, Miller 252 w 30A, Miller super32p12, Lincoln Ranger 9, Thermal Arc 181I with spoolgun, Hypertherm 10000 ,Smith torches. Esab 161lts miniarc.
Reply:Thanks for the reply.  There is a burnback adjustment, which I've never had before.  I thought that only changed things at the end of the weld.  Would it help with the starts too?  Would you mind explaining how to set that?I keep the nozzle of the gun about 1/4" away from the surface when I start, and it's a 1/8" recessed nozzle, so that should give me 3/8" of total stickout.  I clip the wire as flush to the nozzle as my pliers allow, which is probably just a hair more than 1/8".
Reply:Drive roll could be the issue.  Is the groove in the lower drive roll(s) lined up with the inlet and outlet guides? The voltage could be a touch low for the wire speed or the wire speed could be a touch high for the voltage. Spool hub tension could be a little high. Is your contact tip recessed, flush, or extended past the end of the nozzle?ESAB Migmaster 250 Hobart Ironman 230Multimatic 215TWECO Fabricator 181i & 211iHH125EZ - nice little fluxcore only unitMaxstar 150 STH - very nice
Reply:It does stop the wire at the end of the weld. By setting the burnback adjustment you can control the length of wire that extends from the tip. I very seldom clip my wire so I like to set it so it gives me around 1-8 to 3-16 past the tip, I use a flush nozzle, its all in what you prefer. I think your main problem is the wire speed being somewhat high. I would try that before anything else. You may also need more voltage, depending on the type of joint you are welding.Miller xmt304,  Miller S22 p12, Miier Maxstar SD, Miller 252 w 30A, Miller super32p12, Lincoln Ranger 9, Thermal Arc 181I with spoolgun, Hypertherm 10000 ,Smith torches. Esab 161lts miniarc.
Reply:Sound like you're giving your wire a running start into the base metal. Try clipping your stick out length, so that the wire is in contact with the base metal when you start a weld. Since your mentioning short circuit transfer range setting, I'd like to see the contact tip extended past the nozzle an 1/8".ESAB Migmaster 250 Hobart Ironman 230Multimatic 215TWECO Fabricator 181i & 211iHH125EZ - nice little fluxcore only unitMaxstar 150 STH - very nice
Reply:@ ReactorTech - welcome. Also run a S52E like yours via an XMT304.  No burn back control on my S52E.   The "52"s are awesome feeders.  Try baselining 20V @ 300-320ipm.  Also, increase your C25 shielding flow rate to 25CFM and ensure the mill scale removed on the HRS.  Clean, bare metal is key with short-circuit GMAW.Keep us posted bro.Last edited by ManoKai; 04-14-2014 at 10:10 PM."Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:Thanks guys.  The S52 is definitely a beast of a feeder.  Weighs close to what my other mig machines way complete!I'll give the gas and wire feed a little nudge tomorrow and see what it gives me.  I never gave any thought to how much of a running start I'm giving the wire when I cut it back.  That makes sense, I'm losing any advantage to be had with the feeder having to spool up to speed.I can't change the recess of the contact tip without changing the nozzle (or grinding it down, I suppose).  It's the only downside I can think of with the Centerfire consumables.  I'd like to see it flush too, to be honest.  I don't foresee doing any great amount of spraying with this machine, so the recess isn't helping me any.Everything I weld gets cleaned to shiny for at least 1" either side of my weld.  The only thing I don't do is hit it with acetone before I get started.On a feeder like this, what kind of adjustments should I be making each time?  By my math, each mark should give me around 13ipm (it goes from 0 to 100, which translates to 70-750ipm, and the markings around the knob increase by 2 per line, meaning only 5 notches for every 10 settings).  So, should I be 'exploring' by around half a mark (~6ipm) up or down until I get it right, or is that too little/too much of a jump?  I wish the knob was a little bigger so I could see the settings a little better.  Or, you know, digital.
Reply:I would set it at about 40 to start with . I usually go by the sound of the arc to set my wire speed . Grab a piece of scrap angle the same thickness and hold a close arc then turn the wire speed dial to get the sizzling sound. As far as your prep goes I very seldom clean off millscale and the only time I would use acetone or other thinner was if there was oil or grease on the metal, not the light oil coating it comes with such that is on tubing.Miller xmt304,  Miller S22 p12, Miier Maxstar SD, Miller 252 w 30A, Miller super32p12, Lincoln Ranger 9, Thermal Arc 181I with spoolgun, Hypertherm 10000 ,Smith torches. Esab 161lts miniarc.
Reply:@ ReactorTech - for .035in solid wire, 1.6ipm per .001 metal thickness is a good planning/setup rule.  For .030in wire, 1ipm per thousand metal thickness is adequate.  Roughly 70 ipm per major line (1 to 10) on WFS knob.  However, always setup the WFS the same way you described.  The 6s x 10 rule.  And, as you are doing the trial runs to set your WFS just release the drive rollers and (re) wind up the wire back on to the spool.  Saves wire, $.  No need to clip and test and clip at test, etc."Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:Originally Posted by ManoKai@ ReactorTech - for .035in solid wire, 1.6ipm per .001 metal thickness is a good planning/setup rule.  For .030in wire, 1ipm per thousand metal thickness is adequate.  Roughly 70 ipm per major line (1 to 10) on WFS knob.  However, always setup the WFS the same way you described.  The 6s x 10 rule.  And, as you are doing the trial runs to set your WFS just release the drive rollers and (re) wind up the wire back on to the spool.  Saves wire, $.  No need to clip and test and clip at test, etc.
Reply:@ManoKai  It took me a few tries to realize that I didn't need to waste the wire every time I wanted to measure my WFS.   To be fair, it all made it's way to my tig cart for future use, but I don't need to keep a ton of 0.035 filler rods on hand!  Do you find your feeder speed to be a little "off" if you just set it to the number on the dial?  Say you were set up with it turned right to 45, then set up for something else, only to return to the exact settings you were on in the first place, would putting the dial right back to 45 get you exactly the same speed you had before, or just close and still needing a little fine tuning?  I haven't ran enough wire through this one to say for sure, but it does kinda seem that way (hence why everybody sets it by welding with it rather than a technical number).@M J D  do you get a lot of brown soot by leaving the scale and/or light oil on the surface?  Side note -  How do you like the MIG on that Fabricator 181i?
Reply:I don't get much soot, seems like channel is the worst as far as millscale. I use 70s6 wire mostly with 75-25 gas, seems to work the best with minimal cleanup. I don't use TIG much for mild steel so I never got into the extra metal prep thing. Most of my metal prep is removing rust and scale . As far as the 181I I like the way it welds on MIG. I run either .035 or .025 for body panels. I have used 75-25 and co2 with it and am impressed by how nice it works with co2. I don't use it a lot, it was something that works good for portable work where I know I have access to 230 volt. It also does a good job on aluminum with the spoolgun.Miller xmt304,  Miller S22 p12, Miier Maxstar SD, Miller 252 w 30A, Miller super32p12, Lincoln Ranger 9, Thermal Arc 181I with spoolgun, Hypertherm 10000 ,Smith torches. Esab 161lts miniarc.
Reply:Originally Posted by ManoKai@ ReactorTech - for .035in solid wire, 1.6ipm per .001 metal thickness is a good planning/setup rule.  For .030in wire, 1ipm per thousand metal thickness is adequate.  Roughly 70 ipm per major line (1 to 10) on WFS knob.  However, always setup the WFS the same way you described.  The 6s x 10 rule.  And, as you are doing the trial runs to set your WFS just release the drive rollers and (re) wind up the wire back on to the spool.  Saves wire, $.  No need to clip and test and clip at test, etc.
Reply:@ MJD - checkout table at http://www.millerwelds.com/resources...elding-basics/.  The .035 guideline was correct, and my .030 was in error.  You are correct in the burnoff relationship among relative wire diameter.@ ReactorTech - IRT to setting the dial to the aforementioned GUIDELINE parameter and running her, you def have to adjust the WFS (and V) during burn-in for tuning.  Visual/aural feedback during burn, coupled to operator technique and experience, are paramount to optimization."Discovery is to see what everybody else has seen, and to think what nobody else has thought" - Albert Szent-Gyorgyi
Reply:Originally Posted by DanSound like you're giving your wire a running start into the base metal. Try clipping your stick out length, so that the wire is in contact with the base metal when you start a weld. Since your mentioning short circuit transfer range setting, I'd like to see the contact tip extended past the nozzle an 1/8".
Reply:I probably missed it, but did you try a new tip?
Reply:My contact tip was brand new when I started.  Actually, the entire gun and hose were new from end to end.
Reply:try turning the wire speed down a little?
Reply:Ah, you missed my last post.   The problem was the distance I held the wire from the metal before pulling the trigger.  I previously clipped the wire back to about 1/8" from the contact tip, and held the contact tip a little less than 1/2" from the metal.  That ~3/8" distance from wire to metal was the primary cause.  The wire feed was also a touch too high.  I adjusted both at the same time, but it was definitely the distance that was hurting me.I'm still a little curious why my little Hobart actually does better when I give it a little space before I pull the trigger.  I always chalked it up to better shielding gas coverage, but after this fiasco, I'm guessing there's more to it than that.
Reply:Originally Posted by ReactorTechI'm still a little curious why my little Hobart actually does better when I give it a little space before I pull the trigger.  I always chalked it up to better shielding gas coverage, but after this fiasco, I'm guessing there's more to it than that.
Reply:Originally Posted by RodJI learned a lot from reading this.Women are the same way.  And I suspect women would say the same thing about men... each one performs best when respected for how they operate and how much space they need.  LOL
Reply:Originally Posted by ReactorTechAh, you missed my last post.   The problem was the distance I held the wire from the metal before pulling the trigger.  I previously clipped the wire back to about 1/8" from the contact tip, and held the contact tip a little less than 1/2" from the metal.  That ~3/8" distance from wire to metal was the primary cause.  The wire feed was also a touch too high.  I adjusted both at the same time, but it was definitely the distance that was hurting me.I'm still a little curious why my little Hobart actually does better when I give it a little space before I pull the trigger.  I always chalked it up to better shielding gas coverage, but after this fiasco, I'm guessing there's more to it than that.
Reply:Dan, I think he was saying that the problem on the Miller was when he had the clipped end of the wire too far back, and that if he had it closer or in contact with the metal when he starts, the problem goes away. Didn't sound like the Hobart gave him that trouble regardless of being in contact with the metal or the wire having a running start.Maybe I misunderstand??  wouldn't be the first time.