A fairly basic task, installing a head on a platinum shank is a routine process in many small shops. The following project offers some tips and tricks for making the process foolproof every time.
1. Begin by checking the fit of the diamond and the princess head. To make setting easier, choose a head that is about 0.5 mm larger than the stone.
2. You will need to pre-polish the manufactured head.
3. Using a nail file typically used for acrylic finger nails, polish the head.
4. The head is now ready to be attached to the shank.
5. Using a diamond wheel, make a groove in the bottom of the head to accompany the soldering bar on the shank. You should also pre-polish the shank prior to assembly.
6. Tack the head in position with hard platinum solder. This will allow you to make minor adjustments to ensure that the head is straight on the shank.
7. Once you are happy with the position of the head, use medium platinum solder to secure the head in its final position.
8. Inspect the ring from all angles to ensure that the head is secure and straight.
9. Polish the head and the shank interface with brushes and platinum polishing compound.
10. Use a small ball bur to create a seat for the stone. It is important to make room for the corners of the diamond and be sure that no metal is actually touching the tips of the diamond once it is set. This will prevent chipping.
11. Using a pair of setting pliers, carefully pull the first prong in toward the diamond. Rotate the ring and tighten the opposite prong. Repeat for the two remaining prongs. Keep in mind that it takes very little pressure to hold the diamond securely in place.
12. Using a flat needle file, remove the excess metal from the prong tips.
13. Remove the file marks from the tops and sides of the prongs with a silicone wheel, smoothing them out and polishing the prongs.
14. After a final polish and quality inspection, the ring is ready for delivery.
Jurgen Maerz is owner of The Platinum Expert (theplatinumexpert.com), a consulting service specializing in platinum castingand manufacturing.
This article from MJSA Journal, May 2010