Dimensional restoration is a big part of aerospace maintenance.
A whole lot of aerospace tig welding is restoring worn metal.
And that often involves being able to weld a very small bead on an edge.
The thinner the metal, the more difficult it is so its good to start thick and work your way dow...
For 11ga cold rolled steel lap joints its all about torch angle and arc length.
Torch angle is pretty forgiving provided your arc length is tight.
So what is tight enough? The electrode diameter or less works for me