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Devotional for Dads & Kids

Sharpening a Lawn Mower Blade or Knife

Lawn_Mower.jpg

This devotional is designed to be used while you are sharpening a lawn mower blade or knife. This should take about 30 minutes for you to do the task and to discuss this lesson.

Read Proverbs 27:17 “Iron sharpens iron, so one man sharpens another”

Discuss with your kids the job you are about to do:

  • How your goal is to sharpen a dull blade.

  • How a dull blade is inefficient, ineffective, and actually does damage to the lawn (or whatever

you are cutting).

Steps to sharpen the blade of your lawn mower:

  • Safety

    • Prior to attempting

      • Teach about lawn mower safety

        • Blade can cut and is extremely dangerous

        • Motor can be hot and should be touched with caution

        • Danger of debris from the mower discharge

      • Wear gloves & safety glasses

      • Pull spark plug connector from tip and bend away from the mower

      • Drain the gas tank to avoid spills

  • Confirm your blade needs sharpening

    • Grass blades look torn and not cut

    • Grass tips are brown

    • Uneven lawn cutting

    • Dents or nicks in the blade

  • Removing and cleaning the blade

    • Carefully turn the mower on its side.

    • Be sure that the air filter and the carburetor are facing up

    • Find the nut that holds the mower blade to the deck

    • Use a board to hold the blade in place

    • Blade may try to move as you are attempting to remove the nut

    • Use a wrench to loosen the nut until the mower blade releases

    • Take a dry rag and clean the blade before sharpening it

    • If the blade is exceptionally dirty or caked, spray it with some penetrating oil and scrub with a stiff brush.

Tip: To avoid re-installing the lawn mower blade upside down, mark the bottom area of the blade with spray paint or a permanent marker.

  • Sharpening the blade

    Note: Mower blades have a 3- to 4-inch cutting edge on opposite sides of the blade.

    • Clamp the mower blade into a vise or onto a worktable with the first cutting edge facing up

    • Examine the blade and decide if it is better to sharpen it or replace it

    • If your blade has dents or cracks, replace it

    • Blades that are damaged won’t respond to lawn mower blade sharpening.

    • Lawnmower blade sharpening can be done either by hand with files or with a machine like a bench grinder.

    • Only sharpen to a “butter knife” level of the blade.

    • Trying to achieve a razor-sharp blade will make it dull more quickly.

  • Sharpen by Hand

    • Sharpen the edge of the mower blade using a 10-inch file or grindstone, keeping the file at roughly a 45-degree angle

    • Sharpen from the top side of the cutting edge

    • Push the file in one direction along the blade - Do not saw back and forth

      • You should be able to feel the file teeth on the blade as you stroke.

      • If you do not, apply a little more pressure on the file.

    • Follow the angle of the blade edge.

    • Even out any rough spots.

    • Most blades can be sharpened with less than 50 strokes of the file.

    • Finish one edge of the mower blade, then release it from the vice - turn it over to the other edge and repeat

  • Balancing the blade

    • Mowers run smoother when the blade is balanced

    • Sometime, sharpening will remove more metal from one end, causing the blade to not be balanced

    • Check the balance by supporting the blade under its center. You can suspend it from a rod or dowel clamped to the worktable. You could also hang it from a wall nail

      • For more precision, purchase a blade balancer and add it to your mower maintenance tool kit

    • Hold the blade horizontal, then let go - It should remain level

    • If the blade drops down in either direction, it means that the blade is unbalanced

    • Take a few strokes off the heavier end to remove some metal, then retest

  • Reinstalling the blade

    • Wipe the area under the mower clean before reinstalling the mower blade

    • Look for the mark you made earlier - this should make it easy to find the right blade position

    • Use your wrench to tighten the bolt

    • Make sure the mower blade is secure

    • Set mower upright on the ground

    • Reconnect your spark plug wire

Post job discussion:

Question for your kids - What did the file do to the blade?

Discuss how using the metal file allowed you to sharpen the dull metal mower blade

  • Remove dirt and grime

  • Smooth the rough edges

  • Bring the edge back to life

Discuss how the mower will do a more effective job since it can cut better

Discuss how it can now do the job it was intended to do – effectively

Discuss the scripture above and how we as Christians need to allow:

  • The importance of listening to Godly wisdom

  • Expose areas we need to “clean up”

  • The accountability of others sharpens us for God’s work

  • Accountability makes us more effective in our spiritual work