i've been welding for about four years now and have mostly welded aluminum with a snycrowave 200. i just bought a lincoln mp350p welder and a python push pull gun to start a part time fab gig... so my ? is i was runnin .35 4043 wire threw the pythin and running some incredable weld beads no problems at all.. i then switched to .45 5356 wire and counld not for the life of me figure out what went wrong...i was welding some 6061 t6 pipe to some flat 1/4 inch plate(not sure of the spec on that plate) and the wire would just splatter and puke and spit...looked like hell....so i switched back to the 4043 and nothing but perfect welds...so i was thinking the wire may have been comtaminated and have not tired since...any sugestions????