MIG Certification

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Guys I need some insight.  I'm taking my mig cert for all in one.  My test is vertical up, 3/8 plate ....my minimum amps is 176, min volts is 20.... everytime it puddles to the middle even with a weave bead, nned help please, i've been welding for 7+ years and this is embbarrasing.....
Reply:What gas, size wire, class wire, base metal? What code and procedure? And what is all in one??Weldtek
Reply:.035, ER70s, normal carbon steel, I say all in one because the vertical up qualifies me (in one test) for flat, horizontal, vertical etc.....oh its ASTM A36, Argon/CO2 75/25. Code and procedure....AWS D1.1/D1.M?
Reply:In adittion to Weldteks question,for the extra information,I would add a request for info on:Root gap opening dimension Root landing dimensionPrep angle  (- one side of your vee in degrees)I assume it is a full penetration weld.What are the reasons for the miniumums in the the volt and amps settings?. Normally students are free to choose  their settings ?.Are Americam conditions different from Australian ones?  Short arc or Dip transfer mode occurs between 17  to 22 volts. If the pool is too fluid ( this is what I understand from your description ) then either the wire speed must be increased ,thus increasing  amperage and  filling and cooling(truly it does) the pool /or the voltage, which controls the melt off into the molten arc pool, be reduced. An American I liked an admired once schooled me in the six P,s and I have never forgotten themPerfect planning prevents piddling poor performance.If you are  attempting a certificate you should have your weld procedure down "spot on " I have tested hundreds of students for certs here in Australia and the majority of failures have been because applicants forgot their basics.Torch cable straight - good clean earth etc,etc. Every input into the weld process has capacity to affect the outcome for good or bad. If you are to be helped by the blokes here all the info is needed. Do you have an instructor?  It does seem you are attempting this by yourself.  best regardsGrahamenot trying to sound like an arrogant bighead
Reply:Try running more passes, with less deposition in each pass.  Move faster, put down less metal.
Reply:Hey Grahame, "Arrogant Bighead is my job!"If you are testing D1.1, the joint with backing is the B-U2a-GF. But, there is no pre-qualified procedure for short circuiting transfer in that specification. As long as your essential variables are in the globular transfer mode, you should be o.k.Try:45 cfh gas flow23-26 volts200 - 275 ipm130 - 175 amps300 deg. F Interpass temp.B-U2a-GF =  22.5 deg. bevel or 45 deg. included angle, 1/4" root gap, backing strip 1/4" x 3" for x-ray    is it an unlimited thickness test?Weldtek
Reply:Also, there is a technique called a triangle weave. With it you will weave left 2 right straight across the puddle equator, then go up or in towards the root and down or out to the toes. This will take the belly out of the bead, should be perfectly flat when done right.Good lugk!Weldtek
Reply:Thank you all. I will try these suggestions. I work for a nuclear logistics company and there is someone there who will certify me in this. We did find out that there was a problem with our MIG torch or in the gas flow through the line.  It has been replaced but i have been too busy with other projects to try it again. Thanks again and I'll keep u guys updated as best I can.   Its 3/8 plate, 3/8 backing plate with 22 degree bevels and a 1/4 inch gap betweent the bevels.
Reply:Its not working for me. On average it should take about 3 passes. The weld still just drips down in the middle. Any suggestions?
Reply:well turn down your wire feed 10%of what you weld in the flat .and i use an chirstmass tree looking weave or a upside down V, and had to do mine with .045 and 80/20 argon.co2 you,ll get just keep trying ,oh and dont stat in the middel to long paus on the side and wip in to the middel and back to the other sideChuckASME Pressure Vessel welder
Reply:Originally Posted by ByrdWelderIts not working for me. On average it should take about 3 passes. The weld still just drips down in the middle. Any suggestions?
Reply:If it's 3/8" plate, you should be running more than that.  You will likely need at least 2 stringers for a cap, plus your root, and filler...that's at least 5 passes.[/QUOTE]i dont like doing two stringers for a cap on a vertical up on 3/8 plate that is crazy.that is what is sweet with vert,, you can put a wide sucker in there,, just grab those sides and stop worying about your center, move back and forth (this is hard as hell to explain)  but watch it as you go side to side,,you want that red hot metal to form flat lines as you go accross ( i hope you get what i am saying)  hold that side and as soon as it wets in get going accross,, dont #@@# around in the middle,, just make sure that line stays flat and then grab the other side..remember those first passes dictate how the other welds on top of them will be,, dont get carried away on the root or it will be humped and that will screw you up more and more as you go,,, the 2nd pass is deadly for that,, keep it flat or your top pass will be hell