A lot of you guys might know this but for those who don't it's cheap and easy plus it works great. Bring white vinegar to a boil, drop in parts, remove from heat and wait around 20 min. I put the parts in hot soapy water and the bluing or paint rubs easily off. Works as well on aluminum alloy but comes out grey which shines up nicely with car wax. View attachment 100961 The frame was painted but the 2 cylinders and barrel were blued steel.