Painting Over Gold Plate

Question:

We are in the eyeglass business. My question involves both plating and painting. We have a clip-on, which is made of a brow bar and two sets of clips. A lens is cut out to a lens shape, and then the brow-bar is placed over the lens and crimped on with a pair of pliers. The same thing is done with the lower clips. My problem is that the brow bar is gold plated and the clips are black. We currently have these parts made overseas but wish to have a back-up process here in our shop, if things take off. The clips are small; the brow bar is only 0.040 inches in diameter and has to flex without the paint flaking. That's the easy part. Now, the ends need to be masked and painted black with no paint inside of the clip. The clips we plate and then paint over always seem to chip. I believe painting the clips first and then gold plating would be better. Our challenge is that we don't run millions of pieces, and buying masks for painting seems to be costly. I appreciate your thoughts on a solution to this problem. C. M.

Answer:

I agree with your approach. Mask and paint the clips first, and then remove the paint mask and gold plate the brow bar. The black paint will then act as a plating stop-off. Painting masks come in all flavors, sizes and shapes. As far as their cost, I am sure there is one you can afford. Suppliers of painting masks can be found at www.pfonline.com on the "Suppliers" page or in the 2001 Products Finishing Directory and Technology Guide.