METHOD/TOOL

ADVANTAGES

DISADVANTAGES

RISKS to blade

Mill file, or a coarse (60-100 grit) handheld stone

- equipment cheap and readily available

- more people competent in its use

- less desirable edge profile

- wears blade faster

- takes more time than peening

- does not harden edge

- none

Electric grinders

- fast

- readily available (in developed countries)

- much faster steel removal

- best-suited versions are expensive

- many people cannot use one well enough for this task

- removing too much steel

- overheating the steel (depending on specific grinder and how it is used)

Peening jig

- requires less skill

- often faster than freehand

- work-hardens the edge

- requires a minor follow-up treatment with a file or stone

- more expensive than tools for freehand peening

- relative to freehand: none

- relative to filing: blade edge can still end up somewhat uneven.

Traditional (freehand) peening:

Two styles --

a) wide anvil and cross-peen hammer

b) narrow anvil and flat-faced hammer

- can produce potentially best results

- work-hardens edge better than the jig

- tools inexpensive; substitutes easily found

- b) requires no specialty hammer and possibly easier to learn than a)

- requires most skill

- during learning process, blade is likely to sustain some damage

- cracks, wavy-edge or loss of “tension” are nearly inevitable for most beginners, and still occur during intermediate stages of learning

-  waves and tension loss less likely with narrow faced anvil