How do I measure lawn mower blades?
A. Measure the blade diagonally from cutting tip to cutting tip. (measure mulching blades on back to ensure straight line)
B. Measure the width at the widest part of the blade.
C. Measure the center hole.
D. Measure the center to center distance between the outer holes.
Why should I use a mulching blade?
Mulching blades are designed to cut and re-cut grass clippings into fine particles that fall back into the turf seemingly invisible. These reduce particles provide moisture and nutrients that help keep lawns looking great without thatching. Consisting of 85% water, grass clippings provide valuable nutrients as they break down. A season's worth of mulching can actually provide 25% of a yard's fertilizer requirements.
Sharpening a blade is necessary which will allow your mower to continue cutting efficiently.
First, remove the blade from the mower. The leading edge of the blade should be sharpened at a 45 degree angle. The tips of the blade do most of the cutting and will need the most attention. (It is not necessary that the blade be sharp as a knife.)
Before re-installing the sharpened blade, check it's balance. A blade out of balance can cause vibration that may weaken or loosen components on the mower.
Re-install the blade in the right position. Blades are stamped with the part number and word "bottom" on the side that should face the ground. Most blades have fins on their trailing edges. These fins should point up towards the mower deck.
Use a torque wrench to tighten the bolt or nut to the manufacturer's position. Always hand turn blades after installation to ensure proper fit.