Back in '86, I was cutting out 4mm plate for woodstoves. First on a bench shear (try it.. very character building!) Then rigged up an angle grinder on a track. Less effort, but noisy and used many discs. My suppliers invited me to a demo, which included a plasma. So got that and never looked back.
It was a bit crude by modern standards. Not adjustable for amps and three phase. But aced the cuts and the holes that previously I had to cut with hole saws. The slightly rough edges were not a prob, as a quick pass with the grinder and they were ready to weld. Made a huge difference to getting the stoves out.
Today, I cut several thin strips with my Cut50 in 3mm and a couple of 200mm discs in 5mm. All very quick quite clean edges.
The PO's photo shows nothing that needs a plasma. Thin discs work fine. The cross cut can be half done with a disc, then waggled to break the bits that are left. The smaller the disc, as in worn, the less metal left to break out.
KF
If you have any questions on IGBT Plasma Cutte. We will give the professional answers to your questions.