For the love of safety don't use that Home Depot special welder on frames or anything that has any support to anything! The smallest I would use on frames would be something like my Millermatic 135 and even that I would only use for crossmembers. A good all around welder is a Hobart 150 with a bottle of 75/25.
FYI Hobart and Miller now share the same gun. They are swapping over to the Miller style and phasing out the Hobart guns. This way they only have to supply parts for one type of gun now. It runs around 200 bucks for the new gun kit.