well guys i’ve been faceting for 53 yrs and now at 78 i teach it to, even to other oldtimers my ways, actualy any speed for the cutting is fine on my ultra tec i dial half way up, most time about 1000rpm, low speed takes to long and high speed yes you start hydro’ing but i set my drip to just enough to flush cutting not a flood. but right here we change to polish, i dont do what everyone else does. i use a very slowww speed and i use a NONE scored TIN lap with 50,000 grit diamond powder. i use a VERY SLOWWW drip of water enough to make a mud/slur of the diamond. we polish better than 90%+ stones this way with different hardness’s, we need no other lap and works fast if you have a machine with an ac motor using belts/pulleys get rid of the system and get an universal ac/dc perm magnet motor and a speed control. i get speed controls from china about $15-$25 that work great. also one said sweeping back and forth but i’m hoping he finishes aimed straight at the center. just in case there could be a little worpe to the lap. if you have questions email me. gemmakermz@cs.com