Sheet support for a plasma machine?

[m_c]

What Eddy said.
Usual setup for plasma, is strip on edge, that sits in slots in a bar going at 90degrees. That way once the strips get too cut up, it's just a case of lifting them out, and putting in new ones.
Some are set up so the slots are wavy, that way they're held under tension so they're less likely to move, plus it means you're far less likely to end up with a long cut following a support/strip.