MM 251 used with wire feeder?

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i have been contemplating this for some time now as i'm used to the invisions i use at work and the wire feeders for them...i want something comparable in single phase but the internal feeders for the MM's don't run fast enough for me...29.5-32 volts is average use for me and i run my feeder about 760-825 all day long and i want something that can do that and still be single phase and rollable...i could get the MM350 but then we're talk $3.5-4K and that's not feasible right now, but maybe in the future...so my question is this: can you use a feeder with the MM's 210 or 251?
Reply:What size wire???If it is .035 MS the 251 will not output enough volts at those amps.It would be possible to hook up a extra feeder though.
Reply:not sure of the amperage used but i use the invision 465 all day and it runs without any hesitation...the older millermatic 300 we have is set up for .035 and 28-29 volts and wide open on the speed and it is WAY TOO slow for my liking...i've gotten so used to the invisions that i don't mind goin with a lower heat and slowin down SOMEWHAT on the things i will be doin at home but that slow is just awful...feels like i'm waitin for it to weld and burn in...that's why i wanted to know if the 251 can be used with an external feeder and wire spool holder...or does anyone know of a way to convert the three phase machines to single...a guy on hobarts weld site says he has done ot but not to sure if i trust that info...he gives instructs on how to but seems like it would be unsafe or damaging to the machine for some reason!
Reply:What size wire are you using? And what thickness of metal? If you are using .035 wire on materials thicker than 1/4" I'd consider jumping up to .045 and drop your wire feed speed down. .045 will run the best at wire feed speeds less than 600 ipm, any more than that and you run the risk of lack of penetration, the arc or weld may be turbulent, causing porosity, undercut can happen due to the high current (amperage)
Reply:I have one of Millers catalogs right in front of me and it indicates that the Invision 345MP can be set up for single phase.   This is often the case for inverters.   Also rated output drops this  is also the genral case for single phase operation.    You could also look at what Lincoln has in the way of MIP welders, one could make the argument that their 250 and 350MP class machines are a better value than MillerMatics at this time.The question is do you want to invest in a Invision 354MP for the home and be happy with the limitations relative to the 456?   If not you will likely have to put up with the slower machine.    The problem that I see if that you already have a fast wire feed on the Millermatic.   Unless you have one of the higher speed feeders you won't be getting much more speed.    Further you don't have the current available to drive the wire at that speed.   This I believe is your real limitation, that is being able to produce the current to actually make use of a high speed drive.    The high speed drive might work for smaller wire but I would imagine you hitting the thermal limit on the machine along with the current limit easily.    You simply don't have the headroom to do what you want.like all of us you just need to decide how much you are willing to spend to make your home projects go smoothly.   I went cheaper than you did for a number of reasons and I'm sure that will cause frustrations at times.   I just convince my self that the money freed up will go for better things.    I'm wondering though what you are building at home that would require such high speeds anyways?ThanksDave