I'm ok with welding generally, been using gas for years, and MIG for the last 3 or 4, I'm replacing the back wings and boot floor on the Jag, and came to need to do a bit of welding upside down, and couldn't get a neat weld at any price, to the point of suspecting my kit was faulty.

So, tried on some scrap hand held I sarted a weld the right way up, then gradually turned it upside down as it gets upside down the weld wire just melts into a ball about 2mm of the joint. I've tried increasing wire speen, power etc. etc. but cannot get a neat weld, any advice greatfully recieved.

Increase the speed only, about 15% faster should do it, this has worked with every mig I have ever owned, don't touch the power. Test the wire tension using thumb and forefinger, it should not be easy to make the tensioner slip. If it welds well normally the right way up then it shouldn't be the mig that's at fault unless maybe a faulty connection in the gun perhaps

Cheers
David

As above + make sure the earth is good and clean if its not its the quickest way to kill a welding machine

hard to get a neat weld? is it splattering? if so this is probably due to mig gas falling back if welding upside down try increasing gas flow and ensure really clean and good earth.this is what my mate told me and he is a coded welder