We are looking for a navy blue finish for a 304 stainless steel cylinder that is used as a knob on one of our products. This cylinder has a counter-bore at each of its faces and is knurled on its diameter. Ideally, we would like the color to mach our 2024-T4 aluminum part that is anodized. If the finish adds any thickness, then we must mask the part in the critical areas to avoid tolerance problems. The coating we need is purely for aesthetic purposes, but we would like a coating that can withstand some pulling. Any insight would help. D.H.
I would suggest that you use a tinted clear, blue powder coating on this part. These tinted clear powder coatings provide a look similar to anodizing. They will add some thickness to your part (approximately 1.5-2.0 mil or 0.0015-0.0020 inch), so you may have to mask the part’s surface where you have tolerance problems. The knurled surface may not be fully coated because of Faraday problems (at the bottom of the grooves for example). But, this shouldn’t be a problem since the part is stainless steel and won’t corrode.