Any easy way to strip paint of p5’s?

My p5’s havevteh standard blue paint on them is there a easy way to get the paint off?

Are they sand cast aluminium? Regular spray on paint remover works but you’ll need to keep an eye on it.

These were painted black over white, and took a few attempts:


Found a Valor blaster that does a lot of work on old bikes (finned heads ect) will give him a crack.