1.
We had a customer drop off 3 bracelets, one each in diamond, sapphire, and emerald. She wanted them made ¾ of an inch larger. We had to order 4x4 shank material to size them up. It was basically like a ring upsizing but we decided to weld them to prevent a seam. I cut the bottom of the bracelet in the middle like a shank for a ring upsizing.
2.
After the shank is cut I file a bevel on all the sides all the way to the inside as pictured. The angle is about 30 degrees. The filler pieces will be flat butt joints.
3.
I aligned the ends and tacked the two inside corners and then turned the bracelets over to make sure they are straight.
4.
I adjusted the laser to a 1mm beam. Then I ramped up the milliseconds to about 3 and shot in the middle of the joint. I raised the volts until I could see a shiny melt through (when turned over). This pulls metal from both sides of the seam and shows full penetration. Then I used 26 gauge wire at the same settings to fill the joint in two passes.
5.
Both sides are welded all the way through now and it is time to use a rotary burnisher to make sure all the joints are pit free.
6.
Clean the inside first like a ring sizing. Then round it up, check for cracks, and remove any marks made rounding it up.
7.
Now clean up the outside. Lay the bracelet on its sides and file it flat as you would with a ring. Then repeat this on the bottom. Check for any pits and burnish or laser them out.
8.
I preferred to polish the inside at my bench using a 1 in. hard felt wheel on a flex shaft mandrel. There is little chance the bracelet will get away from you as it might with the regular buffer. Use a hard felt wheel to make the sides flat, or a split lap if you have one, and then use a 6 in. wheel for the final polish.
9.
This is the finished sapphire bracelet. I experienced stress cracks in one of the six joints that didn’t show up until after polishing and had to re-laser it. Re-lasering the open crack and one course of filling with 30 gauge wire took care of the joint. After making slight realignments of the clasps the pieces were finished. She loved them when she picked them up.
