Last night I filed, sanded and polished the outer edge of the back side mainly to remove the shear marks left from cutting the blank from the sheet stock. I then soldered the buckle/belt hinge and the pin onto the back. I didn't have a nickle pin so I made one out of sterling. You can probably notice the color difference.
The soldering process produced quite a bit of a copper oxide looking firescale. I quenched the piece in a heated Sparex pickle solution and let it soak overnight. By this morning, most of the worst stuff was gone but I still had to go over the back with a fine arbor mounted steel brush. The front side cleaned up well and I used the same brush on the engraved border lines. They cleaned nicely also. Once again, I went over the front lightly with 1500 grit sandpaper. The buckle is now ready for part of the design transfer. I won't be able to work in the shop tomorrow due to work, but hopefully at night I can get more done on this.
From this angle the hinge appears to be slightly off center (top to bottom), but I believe it is just the angle at which I took the photo, for the same reason the right side of the buckle appears wider than the left.