Learn how to make a ring like this.
Don't forget to check this out: http://divisiblemetalworks.blogspot.com/
Step 1: Materials
First thing you will need.
A Metal lathe.
A Milling machine.
A Oxy torch set.
A Buffing wheel.
And some files.
Then you will need the metal I used a random length of mild steel.
Step 2: Making the Ring
Get your glasses and maybe some earplugs. Then place the metal in the lathe and set it to the right RPMs for your metal I have also done this with aluminum. Start the lathe and cut the outer layer till the whole thing where you are going to make the ring is round then switch to making a whole in the metal. Then remove material till it is almost the right size to fit your finger then cut the ring off the rest of the metal then to the mill.
Step 3: Milling the Cylinder Indentations
Once the ring is cut off the lathe move to your mill and center the ring in the dividing head. Calculate the rotations of the dividing head for the indentations on the ring then get a ball nose bit that is the right size for your ring so it is proportionate. Start the mill set it to the rite RPM and slowly mill out the indentations. (Mill the indentations about 3/4 of the way down the ring so it matches a revolver cylinder) Then run the dividing head till all the indentations are milled.
Step 4: Cleaning Up and Polishing
Finish the ring by cleaning up the sharp edges then round the inside ends so it is slightly beveled and slides on and off smoothly. Then get a glove and put some polishing compound in between the ring and your finger then put the ring on your finger and start polishing it and the inside will be polished some with it as the ring rotates on your finger while polishing the outside. Wash it off when you are satisfied with the polishing and if there is still some lumps of compound and glove on the ring use your nail and some alcohol to remove it then. (optional) To finish the ring completely take it to your oxy torch and heat it non-evenly just till you see the colour change then let it air cool and do this multiple times till it is how you want it to look or just leave it bare steel and polish it really good. IF YOU DO COLOUR THE RING DO NOT POLISH IT AGAIN if its not what you wanted it to look like when you are done with the colour then polish it more and the color will be gone polish it really well then repeat the heating.