Square Shovels - Sharpening Handbook

Square Shovels

Square Shovel

Edge Angle

Sharpening the top edge enables the shovel's back to lie flat on the surface, getting all the material into it (e.g., mulch sitting on a concrete drive, or gravel in the bed of your truck).

A 6" smooth cut machinist’s hand file is useful to carry in your gardening tools box. Use it to resharpen the shovel as needed throughout the tool's usage for the day.

There is no gardening without humility. Nature is constantly sending even its oldest scholars to the bottom of the class for some egregious blunder. Alfred Austin

General Guidelines
α	Sharp ness	Notes
45°	3

Notes & Comments

Shaping the edge

New shovels I have purchased have an angle (α) of 90°. Therefore, initial shaping of the edge is to be expected.

A machinist’s hand file such as a 12-14" bastard file is often sufficient for this task.

If you use an angle grinder, consider using a 120 grit flap disc. A metal grinding wheel may be needed for large-scale shaping. In either case, be sure to not overheat the metal too much: it weakens the metal.

Sharpening the edge

Use a machinist’s hand file.

1. Start with a 8-10" medium (or second) cut file.
2. Finish with a 6" smooth cut file, then use this file to remove the burr.

Example icon

Sharpness Scale

Sharpness scales (as shown in the grey icon to the left) are used to indicate the recommended sharpness for the blades noted above. You can click on any of the icons showing the sharpness scale and be redirected to the page describing this more. Lower numbers are duller; higher numbers sharper.

These are general recommendations; you will need to use your own judgment, based on the knive’s intended purpose.

More Information

Books & Papers

• U.S. War Department's TM 9-867 Maintenance and Care of Hand Tools.

Web Sites

• Matt Stern at The Tool Merchants
  • Garden Tool Care Master List, outlines the tools which help care for garden tools.
  • How to Care for Wooden Tool Handles, gives some good tips.
  • How to Sharpen Garden Tools, provides a good overview.
  • What are the Best Oils for Garden Tools?, reviews the oils he found best for garden tools.