Buffet English Horn Day 16 - 2/28/14

Busy day in the shop today, so all I really had time to do on the english horn was plate that new post and the Eb lever that I cracked and repaired last week. For plating we use a small Caswell Plug N'Plate. It's a pretty simple rig. You hook the cathode up to your part, and the anode in this case is a little chunk of silver on the end of a wand. The plating solution is a liquid with metal salts dissolved in it to make it conductive sot that electricity can pass between the cathode and anode, completing the circuit. As electricity flows, the silver anode oxidizes very slowly, depositing positively charged silver ions into the solution, which are then attracted to the negatively charged cathode, where they bond to the surface.
Normally to use the Plug N'Plate you would wrap the anode in a cloth that you then soak in the plating solution, then brush the cloth on the part you want to plate, completing the circuit. But these parts were small enough that I could just immerse them in the plating solution along with the silver anode.

It took a few tries to get things right. The surface to plated has to be very smooth and perfectly clean for the process to work. Any grease or foreign matter on the surface will prevent the silver from adhering. I had to degrease several times before the silver actually took hold.

When the part comes out of the plating solution, it's completely black. If you've done things right, though, you can wipe off the black crud and reveal the silver plating underneath. Here's how the post turned out. 

Here's a before pic of the raw brass finish for reference.

And here's the Eb lever from last week.

And a before pic. The difference isn't as noticeable in these pictures, but in person the raw brass really stuck out like a sore thumb.