The vapor blaster produces a very clean, sealed surface on cast iron and steel leaving a burnished-like sheen. For most applications this is fine however with cast iron its a brighter finish than I prefer so IMO cast parts need to be treated to dial-in that brown-gray fresh casting color range. Following vapor blasting I use a semi-solid oil and, in the case of spindles and steering arms, bake them at 400 degrees for about 90 minutes to achieve the fresh cast look. As the oil bakes into the cast it heat seasons the metal and also serves as a natural rust inhibitor.
Freshly vapor blasted spindles and steering arms.
Baking in the "Easy-Bake" oven
Before and after heat seasoning (The seasoned spindle appears much darker in the photo than it does in person)
Heat seasoned steering arms