Using a balancer on a mower blade

[JDgreen]

I bought one of those cheap balancers at the local hardware store and I guess it does ok.I had some rusty blades that I cleaned up with a wire wheel and then applied a coat of EZslide as a kinda experment. won't know how that goes till spring. russ

After about 40 hours of mowing my JD blades get a hard crust of grass built up on them and not even a power washer or wire wheel chucked in a drill will take the crust off, I end up using a paint spraper or razor blade holder knife to remove the stuff.

 

[Ric]

My good neighbor was giving me valuable advice and part of what he said was that it is important to always use a balancer. Is there any danger to the mower in general and if a balancer is not easily accessible can one make any modifications?

Your neighbor is right, it is important to always balance your blades after sharpening, an unbalanced blade can lead to heavy vibration, the loosening of internal structural bolts, and accelerated engine wear.
You can buy a table top cone for like $2.50 at the mower shop and buy the metal type the plastic type doesn't work well. The cone will keep the blade centered so balancing isn't a problem.

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[173abn]

yeah Ric,that's what I bought but it's plastic.I'll look for a metal one next time I go to town russ

 

[jross]

Pardon me for asking, but how can you use a Nail to balance a lawn mower blade when it doesn't achieve the center of rotation.

Good question. It is important to make sure the blade hole edge is centered on the nail to achieve a static balance. I do a double check and more than once the blade didn't balance the same twice because i hadn't centered the blade the first time. I am sure there is extra strength built in in engine lower bearings and spindles to compensate for some unbalance. You can balance a blade perfectly and one little stone can nick it, creating some the balance, and more nicks and sandblasting will uneven it more.

 

[Ric]

Good question. It is important to make sure the blade hole edge is centered on the nail to achieve a static balance. I do a double check and more than once the blade didn't balance the same twice because i hadn't centered the blade the first time. I am sure there is extra strength built in in engine lower bearings and spindles to compensate for some unbalance. You can balance a blade perfectly and one little stone can nick it, creating some the balance, and more nicks and sandblasting will uneven it more.

As you said you did a double check and more than once the blade didn't balance the same twice because you hadn't centered the blade the first time, nor can you put the blade back on the nail in the same place twice in a row.

I think it's a given fact that to balance anything you need to find center of what ever you're balancing and when you consider that the hole in a lawn mower blade can be 3/4 of an inch and you set it on a nail it would mean you're already 3/8 of an inch out of center to begin with so how can you balance the blade right.

Magna Matic, Oregon and other company's make blade balancing equipment and they are reasonably cheap and well worth the money if you're going to balance blades frequently and if you're a home owner replacement blades once a year are not that expensive. Not to be argumentative but I'll stay away from the nail myth thing.

 

[grnspot110]

As you said you did a double check and more than once the blade didn't balance the same twice because you hadn't centered the blade the first time, nor can you put the blade back on the nail in the same place twice in a row.

I think it's a given fact that to balance anything you need to find center of what ever you're balancing and when you consider that the hole in a lawn mower blade can be 3/4 of an inch and you set it on a nail it would mean you're already 3/8 of an inch out of center to begin with so how can you balance the blade right.

Magna Matic, Oregon and other company's make blade balancing equipment and they are reasonably cheap and well worth the money if you're going to balance blades frequently and if you're a home owner replacement blades once a year are not that expensive. Not to be argumentative but I'll stay away from the nail myth thing.

Wouldn't really call it a "myth"! I copied this from the operator's manual for my JD F525 mower, built in the early 90's.

By doing it this way, you will be in the center of the blade lengthwise. I use a small screwdriver pressed against a post for stability, check it, the turn the blade 1/2 turn & check again. ~~ grnspot110

 

[Ric]

A nail in the wall is not a balancer!

Using a nail-in-the-wall method to try and balance a lawn mower blade is always a waste of time because the balance reading is not consistent.
The nail-in-the-wall measure of balance is so inaccurate that it simply has no value in reducing blade vibration.
Consistent accurate balance measure can only be obtained at the center-of-rotation i.e. in the center of the lawn mower blade mounting hole.


A nail in the wall is not a balancer! | Magna-Matic Corporate Site

 

[KennyV]

The only place I have seen derogatory things said about the decades old method, nail or fixed pivot, is in manufactures marketing of their 'better idea'...

No matter how you do a 2 dimensional static balance it will be equally good...
If there were any benefit to a perfectly balanced blade you would find dynamic blade balancing ... As far as I know, no one has came up with that unnecessary service ... YET... :smile:KennyV

 

[grnspot110]

Sure seems strange that a major mower manufacturer doesn't know how to balance mower blades!

End of story! ~~ grnspot110

 

[nomow]

A nail is better than not balancing. I make a plastic "plug" to match the blade mounting hole (a star for mine) and layout the exact center and drill a 1/16" diameter hole through. A small finish nail through the hole clamped in a vise provides a more accurate center of gravity. By keeping the "plug" just the size of the blade, I'm able to just hand press the "plug" into the blade and it stays well enough to check balance.
Balance is important to those of us who meet unexpected sticks and stones on our mowing paths and are familiar with the blade condition of "chunks" missing.