Jerry,
In order to weld the sheet metal on these rigs, your MIG welder should be setup to run thin (.023) wire and shielding gas.
The standard floor model at places like Harbor Freight are great..EXCEPT, in an effort to keep the price down, they are outfitted to run flux cored wire and have no gas capabilities.
Flux cored wire is fine, but requires a higher amperage to work properly, and this equates to holes burned through your 19 gauge sheet metal.
Shop for a small 120 volt machine, but make sure it has the ability to run a shielding gas, which allows you to run solid wire at a lower amperage...it will give you a cleaner weld too!
Stuart
