I'm looking for a refrence that explains how to call out brushed finishes. For example Ive seen people call out brush numbers like "#3 Brush", but am unsure exactly what this means.
Well, you are learining. If apperance is important to your product you need to select a supplier and stick with them. finish will vary from mill to mill.
Next time you are in St.Louis look at the arch. You can pick out the three different finihses on the plate.
= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
+1 to Ed...I have some stainless steel PM parts that we have brushed for a customer. The spec is "make it look like our sample". This is something you develop with a supplier, and it will take the two of you time to do so. We spent about 6 months developing a set brushing/polishing procedure which yielded consistent results for our part line.
No two polishes look the same. Even on a single coil of steel the finish changes from one end to the other as the abrasive belts wear finer. If you call out a ASTM finish, which is about all there is, you'll need to impose stricter added specs of Ra if you want consistency. I would require an Ra of 5 to 15 microinch for ASTM #4 and 15 to 30 for a #3 finish. Otherwise you'll get anything from 2 to 40 Ra.