Here is a ten step process to size down a platinum ring and the tools needed to do the job.

Tools needed:
Jewelers Saw
3/0 Sawblades
Dividers
Chain nose pliers
Shank pliers
Chasing hammer
Bench block
Three square needle file
Half round file
Torch with either Natural gas/Oxy or Propane/Oxy
Eye protection (#5 Lens)
Ring Mandrel
Mallet
Sanding stick
Flex Shaft with assorted abrasive and polishing wheels
Tungsten Burnisher
Polishing buff and felts
Platinum Polishing compounds


Step 1:
To size this platinum ring down, begin with determining how much metal needs to be removed. Size s represented by 2.55mm or 1/10th of an inch. Using a divider, mark the area and then cut the shank twice to remove this piece. It is recommended not to cut all the way through on the second cut. Instead, use pliers to break it off. This prevents the piece from flying off and eliminates the need to search for it on the floor.




Step 2:
Bend the two shank ends together with a pair of inside shank pliers. Using a three square needle file, create a chamfer (groove) along the seam. This will help create a strong weld as the metal will fill the groove when melted.



Step 3:
Using a hammer, flatten the piece cut from the ring and insert it into the seam. This will be the filler needed to weld the seam. Because this piece is from the same ring, there will be no color or alloy difference.




Step 4:
With a sharp, hot, oxidizing flame, the piece is melted from the top. This should take les then ten seconds. If it takes longer, the ring will get to hot because of the long exposure to heating.





Step 5:
Continue to weld the ring all the way around until the seam is completed.




Step 6:
Using the half round file, remove excess metal from the seam inside of the ring. The ring will now be ready to be rounded.

Step 7:
Round the ring using a mallet. After the ring is rounded, it should be the proper size. If the fit of a ring is a 1/4 size too small, then it can be adjusted by hammering it to size. This will help to harden the shank and will also make polishing easier.

Step 8:
Using a file, shave the top and the sides of the ring to match the contour. This will erase any evidence of sizing.

Step 9:
Using an abrasive wheel and then sand paper will remove all file marks from the inside and outside of the ring. The inside of the ring is now being polished.

Step 10:
The final touch is done by burnishing the seam, gently sanding the top and then polishing it to the final gloss. After a quality control inspection, the ring is ready to be delivered.




About the author: Jurgen J. Maerz is a recognized expert in all matters of platinum. He is a German trained master platinum smith. For 13 years, he served as the Director of Technical Education for Platinum Guild International. He is now providing his technical support to the entire industry as a consultant. You can reach him at jurgen.maerz.consulting@gmail.com or visit his site.