Grant, the heat build up with CBN is nearly non-existent, so speed is a factor only in the amount of metal removed. Be warned that these wheels will remove A LOT of metal quickly - even on a slow speed grinder. Once you get the feel, then they work great and the result is a keep edge with very little lost metal. A light touch and quick movement is the best method - I suspect with a 3450 grinder, you would need to be very quick.