AArgh! Cosmo 170 mig nightmare

admin

Ok, excuse my faltering mig-gish but Im new to the forum and my patience has finally failed with this darn welder.I am rebuilding a Land Rover 110 from the very rusty chassis on up.I have managed to get my Cosmo gas/gasless mig to let me weld up 2 new outriggers but it has now started to jam and cause bird-nesting at the wire feed on the torch side. I replaced the original torch liner with a metal one but this had a minimal effect.I have now bought a MB25 Euro torch and an adapter kit to swap to a more reliable feed system, but the kit came with no instructions so I am at a loss to know what else to do with the wiring of the kit.Actual fitting of the adaptor kit was straight forward, making a slight adaption to the inlet hole at the front of the machine because of an offset in the euro torch configuration, drilled holes for mounting the plug in the front panel and feeding the gas pipe, wires, guides and main wire feed through into the inside of the chassis.Now, the original torch wiring was a single thin black lead connected to a blue wire from the pcb which was the 12v supply to the torch switch, with the thick high voltage negative supply from the transformer attached to the wire feed body and secured to the chassis. The adaptor kit has a thick black lead with a large ring crimped on which bolts on to the feeder body, and two thin black leads one of which will be the switch supply to the torch but without instructions I cant tell what the second wire would attach to. Maybe a gas solenoid switch? I have set up for gassless operation for now because I am welding the Landy chassis outside and its pretty windy as a rule.The mig wire feeds through on depressing the switch and seems to be ok, but as soon as I apply the wire to the work piece the arc starts but the wire immediately lights up and burns back to the guide tip, the wire jams at the torch, and a bird nest starts at the feeder end.I don't know what else to do.HELP!
Reply:bird nests are generally caused by excessive drive roll tension, if anything goes wrong you want the tension loose enough that you don't get a bird nest.wire burning back - sounds like you need to up the  wire speed
Reply:Clean the liner and tension the roller properly(you tube vids-minimum tension possible).Make sure you have the right roller-wire-tip combo.Fhux core genrally uses a knurled roller.You also have to reverse the polarity to run flux core crap.You should pull the aluminum body off that Brit heap and stick it on a Toyota ! Bubble gumTooth pixDuct tapeBlack glueGBMF hammerScrew gun --bad battery (see above)
Reply:All the aluminium bodywork is gonna be replaced with new bits off Ebay. All the bits I've bought are sitting waiting on a sankey trailer in my front garden.The rusty bits can be replaced easily enough, as long as I can get the welder sorted.