Recently I picked up two new Nortons, a 4K and an 8K. I figured that doing a pyramid would be easier if I didn't have to keep cleaning and flipping the combination stone that I have. With the two new stones I also purchased the Norton flattening stone. Out of curiosity, I decided to try the flattener on the two new stones before using them. After penciling in the cross-hatch pattern on both sides of each stone, I started lapping. Surprise!! Neither stone was even close to flat. After some work, all the pencil lines dissappeared. Now for the test. Did a pyramid with a Henckels Friodur (5/5, 3/3, 1/3, 1/5, 5/20), then finished on a pasted paddle. Stropped 60 round trips on the leather - and boom! Passed the HHT all along the blade! By the way, I also got a great shave.
Just because a stone is new, don't assume that it is flat. In this case, it could have lead to a lot of frustration. My combination stone was much closer to flat than the two separate ones, but still needed a little touch-up.
Just because a stone is new, don't assume that it is flat. In this case, it could have lead to a lot of frustration. My combination stone was much closer to flat than the two separate ones, but still needed a little touch-up.