Q's about MIG spray transfer

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Hello all......I have some questions about MIG spray transfer method.1.  Does the weld bead look different with spray transfer (compared to short circuit)?2.  Is spray tranfer kinda the same effect as a 7024 stick electrode, with the good wash-in charteristics?3.  Can I achieve spray transfer with a MM 175?4.  What gas is recomended for spray transfer?5.  What motion is recomended fro spray transfer?If the bead looks different, it would be great to see a picture....Playing around with my MM 175, using C-20 gas, volts max, wire speed max, I get basically the same bead charactertics (just alot bigger, fatter bead).  the sound seamed the same.Thanks.  Take care.MetalBob
Reply:Technically, I believe that you need 98Ar/2Oxy to achieve what is referred to as a "true spray".  You need at least 90% argon anyways.  With a spray transfer, you should only hear a hissing noise.  Not nearly as noisy as short-circuit.  You really shouldn't use a motion with spray and your bead will look hotter (wider, flatter, more washed in) than a short-circuit bead.  Also, spray is only suitable for the flat position.
Reply:Ok, here you go.  The left is short circuit and the right bead is spray.  It was way too hot for 3/16, notice the uppercut on the top toe of the right weld.  I kept the wire speed the same (375) and went from 20.5 volts on the left to 27 on the right.  .035 wire.  A little note, this may have been globular, not sure.. it hissed and was very fluid.  Also, note how the dirty metal makes the weld look shiney . Attached ImagesLast edited by Doolittle; 03-17-2007 at 07:54 PM.Various GrindersVictor Journeyman torch200cf Acet. 250cf oxygenLincoln 175 plus/alpha2 gunLincoln v205t tigLincoln 350mpEsab 650 plasmaWhen you can get up in the morning, Its a good day.Live each day like its your last.
Reply:Your MM175 won't achieve a spray transfer, as you just can't get the voltage out of it. As far as Argon to Co2 content, you can achieve spray with an 80% Argon 20% Co2 mix, actually if you have a 3 phase welder, such as a Miller Deltaweld 452, Lincoln CV400 etc; you can achieve a spray with C-25, but you need to be around 31-32 volts to do it, the problem with that is in a manual application the operator can't take the heat.  (95 Arg/5 Oxy)will give you a spray transfer at the lowest voltage, which is around 26 volts, the trouble with M5, is it won't give you a deep penetration profile, and produces a really fluid puddle, which makes it tough for out of position work. The 98 Arg 2 Oxy Mentioned in the above post is predominantly used for spray transfer on Stainless steel. Stick with your C20, and if you have a chance post some pics.
Reply:Thx for Pic Doolittle.  Nice to see.SS - so your saying to try it?  Maxed out on WS & Voltage, correct?  Will this be spray transfer then?Thanks for your input guys.MetalBob
Reply:SS - I checked my user guide and it claims the "maximum open circuit voltage DC is 30"...So is this enough Voltage?MetalBob
Reply:You can probably do it with .023 wire.  Give it a shot.Various GrindersVictor Journeyman torch200cf Acet. 250cf oxygenLincoln 175 plus/alpha2 gunLincoln v205t tigLincoln 350mpEsab 650 plasmaWhen you can get up in the morning, Its a good day.Live each day like its your last.
Reply:aaaahhhhh, .023 wire....never thought of that...Good idea.....it will have to wait until Monday as I do not have any.  Used one roll of it, the roll that came with my machine, and switched to .030.MetalBob
Reply:Open circuit voltage is not the same as weld voltage, the actual max weld voltage of your machine is probably more like 21-23 volts, open circuit voltage is the voltage available at the power source output terminals, or negative and positive terminals, this OCV will drop once the arc is struck, several factors attribute to the voltage drop. 1.) Electrode Size & Shielding Gas Used2.) Length, Size and condition of welding cables3.) arc length and wire stickout4.) Type and size of power source. As Doolittle stated, it's possible you could get to a spray with .023 wire, an Argon Oxygen mixture will help as well since the voltage needed for a spray transfer is less with 95% argon 5% oxy. This 95/5 Arg/Oxy mix is a great mix for thin materials in the flat and horizontal position, if you've ever experiencd the difficulty of a mig welder in trying to weld very thin materials, try the Argon Oxy mix as it will run better at lower voltages, 14-16 volts for example.
Reply:Make sure you have an extra contact tip (or three or four).  When you get your wire installed, crank the voltage all the way up and the wire speed.  If you get a bacon frying sound, start backing the wire speed down till it just starts hissing.  thats spray.  The puddle will be real wet.Note:  the reason to have the tip, is just in case you burn back (Its happened to me with aluminum).  Takes the contact tip right out.Various GrindersVictor Journeyman torch200cf Acet. 250cf oxygenLincoln 175 plus/alpha2 gunLincoln v205t tigLincoln 350mpEsab 650 plasmaWhen you can get up in the morning, Its a good day.Live each day like its your last.
Reply:try .035 wire and 95/5 argon/oxy and you should be good to goChuckASME Pressure Vessel welder