As you can imagine, old cars have a lot of rust, which means any restoration is going to include the removal of a lot of rusty metal with numerous holes and gaps. Rusty metal can pose problems for most plasma systems because they require metal to attract the arc. When no metal exists (as is the case when cutting rusty material) the arc extinguishes. The user then has to move the torch over solid metal and re-fire the torch.
If you’re working to cut out a small part with a little bit of rust, this may not be a huge deal, but if you are cutting out an old floor board for instance, this could be a big problem. Not only would you have to keep re-firing your torch, but you’d go through a lot of consumables.
For this reason, the expanded metal feature found on most Powermax systems tends to be a hit with restoration specialists. They can set the Powermax system to the expanded metal mode and cut through numerous rusty panels and expanded metal plates without their arc going out. You can learn more about how Powermax plasma systems can help with automotive work at www.hypertherm.com/newgenplasma.