For those who are more interested in the results than the process, we’ve summarized our test results for impact, wear and ease of sharpenability here.

What were the test criteria?

When we started the process of evaluating new blade materials, we looked at characteristics that woodworkers really care about.

These included:

• How well does the blade handle impact?
• How well does the blade wear?
• How easy is it to sharpen the blade?

With these criteria in mind, we developed a test suite to determine which material performed the best.

What types of blades were tested?

We tested 21 different metals, some with a variety of heat treatments. Included in our test suite were metals that are commonly used in blades: O1, A2, M2 and M4. Every metal was tested with bevel angles of 20°, 25°, 30° and 35°. Every blade was lapped to the Veritas Tools standard of 5μin.

How did we test the blades?

We developed specific test procedures to determine the different performance characteristics of the blades.

How did the PM-V11 alloy perform relative to the other metals?

This graph presents performance on the impact and wear tests. (Note: PM-V11, O1, A2 and M4 are the only named metals.)

Wear and Impact Test Results

The PM-V11 alloy was the clear winner on the impact test, surpassing all the other metals. Most significantly, PM-V11 blades were able to hold a bevel angle of 25° during impact testing. On the wear test, PM-V11 blades tied for the second position.

We tested the top-performing blades on the impact and wear tests (as well as O1 and A2) to assess their ease of sharpening.

Our sharpening tests showed that O1 is still the easiest metal to sharpen, but the PM-V11 alloy was a close second, even a bit easier to sharpen than A2.

Blade Selection and Preparation

As a part of our steel selection process, we developed a long list of candidate alloys for testing. From this list we selected 15 different metals: two cast tool steels (O1 and A2) and 13 powdered metals (PM). Six of the PM blades used two different heat treatments, so in total there were 21 different blade configurations tested. The materials were assigned code letters, so during testing, we did not know which metal was being tested.

All blades were prepared in the Veritas Tools machine shop to the standard Veritas Tools specifications used for blades:

• a lapped face finish of less than 5µin
• a micro-bevel surface finish of less than 16µin

The blades were checked for conformity to the specifications before initial testing began. The blades were tested to measure their hardness as a result of the heat treatment process. Hardness tests were done in four locations on each blade to ensure that the hardness was consistent throughout the material. For the materials used, hardnesses ranged from Rc54.1 to Rc64.4. As points of reference, the O1 blades averaged Rc60.5 and the A2 blades Rc60.6. Following hardness testing, the blades were reassessed for conformity to specifications.

The next step was to sharpen the blades. For consistency in sharpening, the Veritas Mk II Power Sharpening System was used. The blades were tested at bevel angles of 20°, 25°, 30° and 35°. The primary bevel was ground down to 17° using an 80-grit micro-abrasive. The micro-bevel was honed using a four-step process with 100µ, 40µ, 9µ and 5µ grit papers. The lap side was continually honed using 15µ and 5µ papers to remove the wire edge. After sharpening, the surface quality was measured on both the lapped and micro-bevel surfaces. All blades were sharpened to within the baseline of 3µin on the micro-bevel surface.