Skip to content

Sharpness Testing of a Torjiro Petty Knife After Stropping- Video

Knife Sharpness Test After Stropping - Tojiro DP 150MM Petty

David, one of our sharpening specialists, retests a Tojiro DP 150MM Petty Knife on the Edge-On-Up Edge Tester (also called a BESS Tester) after co-worker Dan, stropped it. This knife was first tested brand new and it had an average force of 119 grams to cut the test media.

To test the knife again, we measured the sharpness at three locations on the knife, one closer to the heel, one closer to the center, and one towards the tip. The first test measured 97 grams of pressure. The second test measured 59 grams of pressure. And the last measurement towards the tip came in at 82 grams. The average of the three readings is 79 grams of pressure. With new knives, a number under 200 generally indicates a very well-sharpened factory edge, so while the out-of-the-box sharpness of 119 was very good, the improvement to 79 in quite remarkable for so little effort.

Learn more about the Double-Sided Paddle Strop and the Sharpness Tester we used in this video.