I've got a mini lined up that needs a lot of bodywork done, I've only used a MIG for 1" box section before so am now practicing with thin sheet. (I've also used Gas before). I've an old BOC Migmate 130 and am using BOC Argoshield. I've been practicing Malcom's pulse welding technique, but have noticed that the weld pool takes a second or two to go solid. During the cooling off period should I depress the trigger enough to keep the gas flowing? Trying this last night my welds seemed to look a bit better. One other thing I noticed when trying this was that on the bottom side some of the big 'penetration pools' (hard to describe) had small central pits that were devoid of metal. Does anyone know what would cause this? On another note, when trying to do a 'normal' weld run and not stopping I can see the weldpool is up to about an inch long behind the point I'm welding. This seems to produce a weld that isn't porous, but the surface is dull grey with a thin slag type covering. Is this because I'm moving so fast the gas isn't shielding the weld long enough? I've stack more questions, but my wife's working this weekend and one of our girls has just woken up, better go. Thanks for any pointers, Nial.