Roll it on it's side.

[Stroker McGurk]

Thing I see wrong with the inner tube or mattress idea......What happens when you start welding and the sparks are flying?

The wooden things I like

 

[Sam_Fear]

Couch cushions don't set fire that easy or there'd be a lot more drunk smokers burn themselves to death. But yeah, ya gotta be a little careful. Generally where I was working sparks woulda had to bounce a lot to get to a cushion.