Help understanding setting amperage on Hobart Machines?

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Ok so I'm trying to learn more about how to set a machine up myself rather than just following the door chart.First off I'm working with a Hobart 210mvp. After watching Jody Collier's new series I see that a good rule of thumb was 1amp per .001 of material thickness. So that would imply 125amps for 1/8" material yet 1/4" material needs 250amps? My units manual states it tops out at 220amps on a good power source but claims it can weld up to 3/8" material. At what point does the 1 Amp per thousands stop applying and then what does apply?Wire speed I'm pretty ok with on getting right. My issue is guaranteeing my welds are hot enough the first time around.My other question is I don't quite understand how the taps work on hobart machines. As per the chart below from the manual, on 115v I can achieve 170amps at the max setting. At the same time the door chart suggests using the max setting for 1/8" when running 115v. So by the above 1/8" should be ballpark 125 amps, but I'm using potentially 170 which would imply too much?Attachment 806371Attachment 806381
Reply:The door charts are a refrerance point not an exact thing, every machine welds a little different.The 1 amp per .001 kinda quits working after the 1/4" mark. I'm not real familiar with the 210 MVP but usually 220 amps is just enough to break into 5/16 for full penetration. I typically add about 25 -30 amps for every 1/16" over quarter then fine tune from there (1/4" usually runs about 200 amps depending on what you want the puddle to do)I'm pretty sure miller has a chart on their site that gives you amps, wire speed etc...Ps all welders designed to run on 110/220 always work more efficiently when hooked to 220vReal welders know how to penetrate!(Equipment)Whatever can be used to beat my opponent into submission!
Reply:Originally Posted by BrooklynBravestMy other question is I don't quite understand how the taps work on hobart machines. As per the chart below from the manual, on 115v I can achieve 170amps at the max setting. At the same time the door chart suggests using the max setting for 1/8" when running 115v. So by the above 1/8" should be ballpark 125 amps, but I'm using potentially 170 which would imply too much?
Reply:Originally Posted by MeltedmetalOperative word is "potentially". The taps are adjusting the voltage, the wire speed is adjusting the amperage.---Meltedmetal
Reply:In the included link they are recommending about 500ipm to start for 1/4 material with .030 wire. You can always cut some coupons and bend test them to see what works best. ---Meltedmetal http://www.weldingtipsandtricks.com/...g-started.htmlOkay excuse me I am out to lunch to-nite. I misunderstood what you were saying. If I now comprehend you are plugged into 115v. The door chart is suggesting the max voltage setting for 1/8 steel and I would say that your wire speed should be around 250 ipm and by your chart you will also be at about 10% duty cycle(1 minute on + 9 minutes off). Increase your wire speed and you decrease your duty cycle on that size of machine. If you can hook up to 220v you will like your machine better. Sorry if I am being thick to-nite its been a long week.---MeltedmetalLast edited by Meltedmetal; 08-15-2014 at 08:09 PM.
Reply:Yea I'm using the same chart already. I get that what I am trying to figure out is how much amperage value each tap on the machine is worth it doesn't make sense to me.
Reply:Check this out, beginning at about minute 25.  Miller Multimatic 255
Reply:Given that the hobart machines are tapped voltage settings, I usually start with the door chart and do this:  Miller Multimatic 255
Reply:If we are speaking about 115v, you use the 2 chart you put in your first post. Pick a duty cycle you can live with say 10%. To stay within that you will be at about 130 amps or with .030 wire around 260 ipm. Voltage setting 4 won't cut , 5 probably not either. 6 maybe and 7 possibly. your limiting factor is going to be your duty cycle. Heat in your weld is not a function solely of amperage(wire speed) It is a function of v*a, 100 amps on 7 will be hotter than 100 amps on 5. If you try to crank it higher you will run into the duty cycle and shortly after the inability of the machine to maintain the required output. Even though it is call a CV machine you will notice that the voltage is dropping as you push the current higher. When it gets low enough you won't hold the arc. You likely want to think of 15v as the very bottom of where you want to be.---Meltedmetal
Reply:Brooklyn           See if this helps, you have two parts of a welding 'equation' Amperage-think of that as similar to gallons per minute, and voltage think of voltage as pressure in a water system ie psi.       In electrical terms voltage multiplied by amperage gives you VA or volt amps- more commonly thought of as 'watts' when it is doing work such as welding.      The more watts you have the more 'heat' you have to do work with in this case melt metal. So when you do the wire speed calculation vs thickness you are calculating along the line of how many 'gallons' per minute do I need- in this case though it is amps which is a measurement of how many electrons are moving in a unit of time (trying to keep this simple).  The pressure or voltage is what the taps set on the machine. So the higher number you set the more voltage or pressure behind those electrons flowing. Too little as Jody shows in his video you popping and poor performance- too much and you get spatter and possibly burn thru the material.   So when you do the wire speed or 'amperage' setup you are determining how many 'gallons' you need- the unknown part is at what pressure (voltage is electrical 'pressure') Generally the door chart gives you the correct pressure (voltage) it is just the wire speed that might need a bit of tweaking.  The others have addressed the 1 amp per .001 above .250. Hope this might help
Reply:Understand,that the voltage and amperage required to weld any material thickness is going to vary depending on the joint design or the position that the weld is being performed at. The voltage and amperage required can also vary between wire brands. And if this isn't confusing enough, voltage and amperage will be different depending on whether your running solid wire  or self shielded wire. It's also going vary with solid wire based on the shielding gas you are using. The V/A curves you are referencing for your machine are based on a 115V input. You more than likely have a 120V plus input, so the actually slopes that your machine outputs are going to be higher then what is on the supplied graphs. To run a solid wire at 170 amps with C25 is going to require around 19 volts. A self shielded wire requires less voltage, but you still don't have enough available output voltage to get 170 amps out of a 120 v input from tap 7. Based on my experience from running tap 7 off a strong 120V  dedicated  30 amp circuit, with solid wire the top end is around 140 - 150 amps.Truthfully, I feel Jody created more confusion then help in his last video. Stop worrying about the numbers. Instead get some scrap play with machine settings until you find out what works best for the joint design and position of the weld.ESAB Migmaster 250 Hobart Ironman 230Multimatic 215TWECO Fabricator 181i & 211iHH125EZ - nice little fluxcore only unitMaxstar 150 STH - very nice
Reply:Originally Posted by DanUnderstand,that the voltage and amperage required to weld any material thickness is going to vary depending on the joint design or the position that the weld is being performed at. The voltage and amperage required can also vary between wire brands. And if this isn't confusing enough, voltage and amperage will be different depending on whether your running solid wire  or self shielded wire. It's also going vary with solid wire based on the shielding gas you are using. The V/A curves you are referencing for your machine are based on a 115V input. You more than likely have a 120V plus input, so the actually slopes that your machine outputs are going to be higher then what is on the supplied graphs. To run a solid wire at 170 amps with C25 is going to require around 19 volts. A self shielded wire requires less voltage, but you still don't have enough available output voltage to get 170 amps out of a 120 v input from tap 7. Based on my experience from running tap 7 off a strong 120V  dedicated  30 amp circuit, with solid wire the top end is around 140 - 150 amps.Truthfully, I feel Jody created more confusion then help in his last video. Stop worrying about the numbers. Instead get some scrap play with machine settings until you find out what works best for the joint design and position of the weld.
Reply:Louie1961> "Check this out, beginning at about minute 25." Nice video for beginners.... all 45 minutes of it.MM 211Smith Tru Lite O/A set, Thanks Bob!Lincoln AC-225--But you must not change one thing, one pebble, one grain of sand, until you know what good and evil will follow on that act. The world is in balance, in Equilibrium- Ursula K. Le Guin
Reply:Yeah his videos are great. I feel bad that they are all over the web as they guy is losing out on money he deserves to make.Miller Multimatic 255
Reply:On a tapped machine I'd worry less about volts/amps than actual bead appearance.  One follows the other, so to speak.Set your wire speed down near the bottom.  Let's say 10-20.  Set your voltage to the middle somewhere, around 2-3.Lay a short bead on the stuff you're gonna actually weld (scrap preferably), and observe the appearance of the bead.  It it's high, and ropy/peaked.....you're running too cold.  Juice it up a notch, and repeat.  Keep turning up the voltage till you start to have burn through problems, then dial it back a notch.  Always to to the edge of burnthorough, then dial back if necessary. When volts are set right....the bead should be fairly flat, low, and spread out, to some degree.  Now you're in the zone.Next it's wire speed.Turn it up till it starts to stub in the workpiece, then dial it back to where it makes a nice bead.  Again, it's all about appearance.  Forget the numbers, and LOOK at the bead.  The numbers are handy when you have it dialed in, for a reference point at some future date.For thin stuff....low volts, low wire speedFor average stuff.....mid>high volts, and wire speed from low to mid range.You can increase voltage when you want to run fast, and lay down more material.  After the voltage increase, bump up your wire speed, and increase travel speed.I really feel that when someone learns to wire weld, or even stick weld, that the numbers should be covered up, and the student forced to figure out how the machine runs with a particular consumable, and how it runs on different thickness metal, without relying on numbers that really only reflect a ballpark setting."Any day above ground is a good day"http://www.farmersamm.com/
Reply:AND ROFL, your settings will likely change as the machine gets hot from extended use, or the material starts to get hot from repeated welds in one area.  It's all about looking at the puddle, and the bead"Any day above ground is a good day"http://www.farmersamm.com/