Since dross is the resolidified metal that clings to the bottom of the plate from plasma/oxyfuel/laser cutting applications I suspect that you mean (in your post) that you want no dross or minimal dross.
Dross formation from plasma cutting is a function of:
1. Torch and plasma system design. Not all models and makes are equivalent. There are also different processes such as air plasma, oxygen plasma, nitrogen and argon/hydrogen plasma's as well as high definition plasma systems that produce different results dpending on the use and application.
2. Choice of consumables and power level will determine cut quality as well for a particular material and thickeness. The major plasma brands offer systems with multiple consumable choices (such as FineCut for thin materials, 45 amp, 65 amp, 85 amp and 100 amp consumables for thicker or faster cutting) while some of the lower cost plasma systems rely on 1 set of consumables for all thicknesses....resulting in poorer cut quality.
3. Motion control, cut speed and torch to work distance are all critical to control cut quality and dross formation. Major plasma manufacturers provide detailed cut parameter charts that outline the best practices and settings for best cut quality on a given material and thickness.
If you provide a little more detail about what you need to cut, is it a hand held or mechanized application.....and is there a price limit...and we'd be happy to offer better advice!
Jim Colt Hypertherm