Lawn Mower Balde - Sharpen & Balance

[MasterSolenoid]

Question: How do folks on here maintain their lawn-mower blades ? Recently I wanted to sharpen and rebalance mine (Toro, walk behind). Problem: The angle was way off from repeated sharpenings and I suspected the balance was off. I tried balancing using the round shank of a screw-driver / this seemed to work and did repeat.(The nail in the wall method) Then I came up with a better idea (after seeing the $100 Balancers on E-Bay). I bought a small Roller Bearing hoping it would reduce any resistance and turn more freely. I also bought a Acme Thread Gage which is 30 degrees. With the Bearing inserted into the blade and then slide onto screw-driver shank, the balance was now showing as being OFF. I checked for repeatability and the results were consistant. I'm more inclined to believe the bearing. If anyone is interested, this is what I bought:

 

[4WD]

Interesting … What are you doing to balance ? Grind some steel off the heavier side ?

 

[atikovi]

Why balance mower blades? It's just a pound or two of solid uniform steel. If it's so bent out of shape, you need a new one.

 

[MasterSolenoid]

Originally Posted by 4WD

Interesting … What are you doing to balance ? Grind some steel off the heavier side ?

Just resharpen and keep checking balance. It should not take much effort to get acceptable. Every thing has a tolerance. Mostly I want to confirm there not way off balance.

 

[EricG]

Don't over-think it. Less than $5! https://www.amazon.com/Oregon-Mower-Blade-Balancer-42-100/dp/B000VYFOJM

 

[Kira]

We lay a dowel down and set the blade atop as if making a see-saw. I like the Oregon cone EricG linked to. It's how the Sunoco station used to balance our tires.

 

[JHZR2]

Nice idea, but I've found that it's hard to find bearings in most box and hardware stores. Guess that's why you used McMaster?

 

[Eddie]

Nice idea. Presently I use a 16p nail. Ed

 

[MasterSolenoid]

Moderator - Can you move this to: Forum: Lawn Mower and Small Engine

 

[gman2304]

Originally Posted by Eddie

Nice idea. Presently I use a 16p nail. Ed

This!

 

[FA_WRX]

I bought a sharpening and balance kit from Lowes, works well. You just sit it on the bench and center the blade. Grind on the low side of the blade, re-center on the piviot , and repeat. until it sits level.

 

[4WD]

To be honest … my 42" shakes more since I sharpened the blades … so just went to Sears parts direct for a new pair. Figured with an extra set I'd spend more time to sharpen and balance the offline pair …

 

[andyd]

Nothing as fancy as all that. I alternate passes on the bench grinder What I take off one edge, i take off the other side too. Just like an algebraic equation. Lawn mower blades don't have to be razor sharp. A new blade isn't beveled to a sharp edge. There is a ~32" of blunt edge that starts the cut. I used to sharpen at the start of every season, Now I check the grass. If it is cut cleanly, not ragged or torn, the blade is doing its job and doesn't need sharpening.It is a less is better kind of thing. Any lawn care pros out there? What do you guys do? TIA

 

[4WD]

Originally Posted by EricG

Don't over-think it. Less than $5! https://www.amazon.com/Oregon-Mower-Blade-Balancer-42-100/dp/B000VYFOJM

Got one off eBay that also had a proper angle grinding stone …

 

[MrMoody]

Originally Posted by atikovi

Why balance mower blades?

A blade that's off balance creates more wear & stress on the engine crank & main bearings (or deck bearings), not to mention vibrates the mower apart, makes your hands tingle, etc.

 

[dwendt44]

[img]https://i.ebayimg.com/thumbs/images/g/lRMAAOSwESdcuwXj/s-l225.webp[/img] $7.10.

 

[LoneRanger]

Mower blades are throw away items now days, like everything else. China.

 

[spasm3]

Originally Posted by LoneRanger

Mower blades are throw away items now days, like everything else. China.

I use them for years. I have 3 sets for the zero turn. 2 sets of regular blades, that way a sharp set is always ready to swap on. I have a gator mulch set that I use for the last couple of mows of the fall and the first 2-3 mows of the spring. I use the smallest diameter nail I have to check mine. I check the balance closer on the pushmower since the blade is basically mounted right to the crank.

 

[MrMoody]

1. Even if they're cheap, it's a shame to waste them. 2. Even the new ones have doubtful balance.

 

[JerryBob]

Originally Posted by EricG

Don't over-think it. Less than $5! https://www.amazon.com/Oregon-Mower-Blade-Balancer-42-100/dp/B000VYFOJM

My last two lawnmowers did not have a round hole in the blade, it was an irregular shape. I have one of these, but it no longer works. I pop the blade off every month or so, and hit it with a file. I'm not sure balancing really matters unless it's really unbalanced. But I buy cheap Sears push mowers and just don't worry about it.