How to polish your gravers can depend on several things. Most important would be the metal that the blank is made from. Then the purpose of the graver, the material being cut, and finally the geometry results you are looking for may be affected by your method of pre-polishing and polishing.
The most common metals and methods I see used for gravers blanks are:
Carbon steel - 4/0 pre-polish, Simichrome or stainless rouge final polish - OR 1,200 pre-polish to 50,000 diamond polish
M2 - 4/0 pre-polish, Simichrome or stainless rouge final polish - OR 1,200 pre-polish to 50,000 diamond polish
Water hardening drill rod - 4/0 pre-polish, Simichrome or stainless rouge final polish - OR 1,200 pre-polish to 50,000 diamond polish
High speed steel - 4/0 pre-polish, Simichrome or stainless rouge final polish - OR 1,200 pre-polish to 50,000 diamond polish
Cobalt high speed steel – gets harder to polish but can still be done with above – diamond begins to be a better/quicker solution…
"Carbalt" - diamond only, some heel angles on the “Carbalt” gravers are put on entirely with 50,000 grit diamond, and for these there is no pre-polishing step.
Tungsten Carbide – diamond only, some heel angles on carbide gravers are put on entirely with 50,000 grit diamond, for these there is no pre-polishing step.
Almost all final pre-polishes (example 4/0 paper) are applied ACROSS the graver heel, instead of lengthwise. The reason for this is that if you accidentally include a few tiny scratches, they will not affect the "bright" cut - since they run in the opposite direction.
Polishes are applied across the heel of the graver when using the 50,000 diamond charged ceramic rotating wheels, but that is more difficult to do when polishing on strops made of cardboard, leather or hardwood. Care must be taken to keep the corner edge of the graver from catching or digging in and tearing these materials. You must also watch out that the softer materials don't roll or blunt the cutting edges on the corners/sides of the gravers.
I favor both right and left handed "half point" gravers for bright cutting around bead set stones. These are shaped like an onglette sliced vertically. Pre-polished on worn 4/0 paper, and finished with Simichrome and/or 50,000 diamond paste.
For actually raising beads, I use mostly # 51, 52, and sometimes 53 round gravers. These round gravers generally do not require polishing, though they do often get a very short heel depending on the application. They are used as "wedges" to raise up the material to form a bead. Of all the gravers on the setting bench the round and onglettes probably get sharpened the most often because the tips are vulnerable.
Ornamental gravers, especially "Liners" are not polished in the same manner as setting gravers. Because the "teeth" are the very reason they are used, care must be taken not to damage them. Polishing them is done lengthwise - in the direction of the lines. First the oxides that form during manufacturing or your own "alterations/bending" must be removed from between the "teeth." This can be done on the coarser liners (example: from 32/12 to 16/12) with FINE valve grinding compound available at an auto supply. This grease based paste is applied to a wooden block and the gravers stropped lengthwise until all the firescale has been removed. Final polish is done on leather with Simichrome and/or 50,000 diamond paste. Liners from 14/12 on down to 6/6 for example are done on a separate wood block with 12,000 diamond paste, and finished on the leather strop. The reason for the wood block and leather strops is to force the abrasive up into the grooves between the teeth. NEVER try to polish the teeth of a lined graver on a polishing lathe - you will roll over and blunt the lines, making the graver useless.
My leather and cardboard strops are prepared with BOTH Simichrome or stainless rouge and 50,000 diamond because I strop carbon steel as well as the harder alloys like "Carbalt" on the same strop. Simichrome will do fine on alloys up to high speed steel, but it will do nothing to a carbide or "Carbalt" graver. I generally strop and lubricate while engraving - about every 7th or 8th cut to remove the "plating" or residue that builds up on the graver tip with certain metals. Copper and aluminum are notorious for this." >
These methods work for me. As with anything else there are other methods. Try ‘em all! Post your results and preferences! If you have further questions, post them too. I'll try to get them answered a wee bit quicker...
Brian P. Marshall
(Copyright Brian P. Marshall)