Endless welding. Not going well

[semtexsteve]

Hi all. I am at a stage that my chassis is about 90% cut and tacked together but I am struggling with my welding. I can weld offcuts on the bench with OK results. I have cut some to see the cross section and penatration and all seems fine. I am using a gassless mig which apart from the extra splatter does a nice weld. I have anti splatter spray for that. The issue is as soon as I try to actually weld the chassis it looks like I have never even seen a welder before let alone used one. Getting a bit fed up now. Any advice would be much appreciated thank you.