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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?

I have been clamping mower blades in a vise to sharpen them with files for over 35 years, really, the only "Balancer" you need is a finish nail driven into a wood block. Just hang the blade on the horizontal nail and if the blade is unbalanced the heavy end will be lower. I have NEVER had an unbalanced blade, because by filing you remove so little material from each end the blade usually remains well balanced.

I have been filing my blades for years, not taking to much off . and then more recently (3 years ago) i have been using a angle grinder because it is quicker for me,but i never used a balancer or even a nail set up like jd green uses(and jd does like most people and lawn service co's. do) which i think is a good thing. the thing is that if you don't balance the blade(s) "supposedly" you may experience vibration on the mower , which i never have felt. there is a mower blade sharpener/cleaner from ...magna-matic.. that is suppose to be the cats.....for sharpening and cleaning the grass and rust off the blade, but the price is (imo) so high that i dont see how a person can justify owning one.but many people on a different forum swear by them.

LandN said:

I have been filing my blades for years, not taking to much off . and then more recently (3 years ago) i have been using a angle grinder because it is quicker for me,but i never used a balancer or even a nail set up like jd green uses(and jd does like most people and lawn service co's. do) which i think is a good thing. the thing is that if you don't balance the blade(s) "supposedly" you may experience vibration on the mower , which i never have felt. there is a mower blade sharpener/cleaner from ...magna-matic.. that is suppose to be the cats.....for sharpening and cleaning the grass and rust off the blade, but the price is (imo) so high that i dont see how a person can justify owning one.but many people on a different forum swear by them.

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I have thought about using my angle grinder but would hate to take too much metal off a cutting edge so I don't do it that way. Do you use a metal grinding wheel of any certain grit? Coarse or fine?

JDgreen said:

I have thought about using my angle grinder but would hate to take too much metal off a cutting edge so I don't do it that way. Do you use a metal grinding wheel of any certain grit? Coarse or fine?

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its just a cheapie black and decker 4 1/2 " grinder with a black and decker wheel but no indication of coarseness(unless "type27" means anything) but by feeling it i'm saying med/fine....i'm sure you wont have a problem with your blades just practice on a old scrap piece of like steel and "finesse" it you'll be fine with it,:thumbsup:

LandN said:

its just a cheapie black and decker 4 1/2 " grinder with a black and decker wheel but no indication of coarseness(unless "type27" means anything) but by feeling it i'm saying med/fine....i'm sure you wont have a problem with your blades just practice on a old scrap piece of like steel and "finesse" it you'll be fine with it,:thumbsup:

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Thanks...a B&D grinder cannot be any worse than my "Crapman" grinder....:laughing::laughing:

4 1/2 inch grinder is quick & easy... Just a light touch, will keep it sharp and in shape, don't get too carried away and burn a hot spot into the metal...
I have also used a file.
Balancing a blade is not going to be a big issue. If you have a blade that is in such bad shape that its out of balance ... YOU probably need a NEW BLADE...

There is going to be someone that will sell you anything they can convince you that you need...
If you really feel that a co$tly balancer is needed ... then you should get an even MORE co$tly Dynamic balancer...that will really spin it up and computer balance it.:biggrin:
If your blades are not clean and rust free enough, you might look at having them powder coated while you have them off to resharpen :laughing:...

Reasonable care when sharpening a wire brushing and a nail will work fine... :smile:KennyV

$ 1/2" angle grinder, balance check, back on the machine.
easy, peasy, lemon squezey:smile:

JDgreen said:

I have been clamping mower blades in a vise to sharpen them with files for over 35 years, really, the only "Balancer" you need is a finish nail driven into a wood block. Just hang the blade on the horizontal nail and if the blade is unbalanced the heavy end will be lower. I have NEVER had an unbalanced blade, because by filing you remove so little material from each end the blade usually remains well balanced.

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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.

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

173abn said:

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

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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.

mois25 said:

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?

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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.

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

Ric said:

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.

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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.

jross said:

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.

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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.

Ric said:

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.

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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

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

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

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

End of story! ~~ grnspot110

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.

KennyV said:

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

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Here's a dynamic blade balancer for ya - Magnetic Blade Balancer, 7-05987, 9788, 42-016-0, 95-2002, 42-016

Unnecessary? Hardly! Works way better than the cheap stepped-cone level static balancers and holds the blade perfectly centered on a smooth tapered cone instead of a stepped cone. The cheap level balancers won't work with all blades since some blades have a star pattern and the tips of the stars don't sit in the center of the steps. This balancer also has a moveable arm to check for a bent blade. Laying a blade on a flat surface doesn't always work but with this balancer you can slowly rotate the blade and the arm can be set to just touch the tip of the blade as it passes and then you can compare it to the other end of the blade.

Just for grins, I balanced a blade on a cheap stepped-cone balancer and got it balanced to the point that it couldn't get any better and then I checked it on the dynamic balancer. Guess what? Yep, out of balance enough to set up a vibration so I'm sold on dynamic balancing and nothing anyone says could change my mind.

I fully realize the price is out of reach for most homeowners but I own one of these balancers and sharpen/balance blades for others as well. It pays for itself.

Lawnranger said:

Here's a dynamic blade balancer for ya
...
Unnecessary? Hardly! ...
...
... I'm sold on dynamic balancing and nothing anyone says could change my mind.

I fully realize the price is out of reach for most homeowners but I own one of these balancers and sharpen/balance blades for others as well. It pays for itself.

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It would have to pay for itself... Because That is Not a Dynamic Balancer... That's still a static balancer, tho with magnets and spring loaded cone....
But like I said any static balance will do an adequate job. There really is no need for Dynamic Balancing Mower blades.
There are a few gimmicky balancing systems available, Some handier to use than others, some very pricey, But they are all static balancers... I have Never seen a Dynamic (mower Blade) balancer.

But we are in a system where marketing will provide the Need for a product... so I'm fairly sure that eventually someone will market it, (needed or not), and like most everyone, I will have to check it out. Till then Pick the system that works Best for you & be happy that no one is trying to sway you into thinking you Need to Dynamically Balance a Lawn Mower Blade... Yet.... :smile:KennyV

KennyV said:

It would have to pay for itself... Because That is Not a Dynamic Balancer... That's still a static balancer, tho with magnets and spring loaded cone....
But like I said any static balance will do an adequate job. There really is no need for Dynamic Balancing Mower blades.
There are a few gimmicky balancing systems available, Some handier to use than others, some very pricey, But they are all static balancers... I have Never seen a Dynamic (mower Blade) balancer.

But we are in a system where marketing will provide the Need for a product... so I'm fairly sure that eventually someone will market it, (needed or not), and like most everyone, I will have to check it out. Till then Pick the system that works Best for you & be happy that no one is trying to sway you into thinking you Need to Dynamically Balance a Lawn Mower Blade... Yet.... :smile:KennyV

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Actually, the magnetic holder, tapered cone and blade spin on a bearing so in fact it Is a dynamic balancer. If you haven't had a chance to try them yet, I highly recommend them as they are far superior to any other method of blade balancing.

The large flat base mounts on the wall and the cone points out toward you, this balancer does not sit flat on a table such as the stepped cone static balancers. By mounting the balancer on the wall you will be able to watch the blade rotate and the heavy end will rotate down as the lighter end of the blade will rotate up-the beauty of dynamic balancing.

Here is how Webster's Dictionary defines static: 1 exerting force by reason of weight alone without motion, 2 of or relating to bodies at rest or forces in equilibrium, 3 showing little change, 4 characterized by a lack of movement, animation, or progression, 5 standing or fixed in one place.
In layman's terms we could say "not moving"

Here is how Webster's dictionary defines dynamic: 1 of or relating to physical force or energy, 2 marked by usu. continuous and productive activity or change
In layman's terms we could say "moving" or in this case, rotating since the blade rotates in order to check for an out of balance condition.

So you can see that since the blade on the balancer I made reference to spins it is now defined as a dynamic blade balancer.

Back in the day we used to use a static bubble balancer for balancing automotive tires but the problem is that you could not dynamically balance them and as a result the tires could still be out of balance even though the bubble indicated they were in balance. Enter in the dynamic (spin) balancers and a whole new world of tire balancing was opened up and the service people were now able to better balance the tires on an automobile providing better service and this is what this dynamic blade balancer provides for lawnmower blades.

I've heard it said "you get what you pay for" but I don't agree with that statement as much as I agree with "you don't get what you don't pay for"....:smile:Lawnranger

I employ the same method for my ride on & push mower blades as I use for my farming mower blades (multi blades of 3ft+) used in tractor slasher (bush hog) combinations where the slasher can cost upwards of $8K & is subject much greater potential torsional/imbalance loading due to size/power transmission of 100hp+ :-

Check blade horizontal & vertical balance after sharpening by centering blade on bolts of a similar dimension to those used for securing on the implement (i.e. static balancing) - I've gone a little further creating simple jigs with the various specific mounting sizes derived from free spinning bearings mounted on bolts with balanced steel templates to handle my single/dual/tri/quad blade combinations (in all using scrap + a few purchased bits cost me less than a set of blades & far less than any single balancer marketed which would handle my blade range), to date after many years of 300 -1400hrs+/yr experiencing no adverse effects due to my lack of "dynamic balancing".

Being a "bush mechanic" having maintained/rebuilt/manufactured all manner of tractors/trucks/vehicles/equipment (also with a little engineering background working for Auto/Capital Equipment OEM's), I am a little sceptical of the need for dynamic balancing on mowers as ultimately all the effort is out the door once the blades are installed as the deck, spindles...etc are not operating consistently in a perfect world due to the variables such as machine &/or terrain conditions- the blades in use experience individual wear rates also influenced by the variables of grass density, moisture content, centrifugal force, hard object impact, travel speed..etc...each rotational cut......I'd suggest on a mower there's a far greater chance of false brinelling occuring under idle conditions than any consequential wear/damage from lack of dynamic balancing....

There are several ways to use a static balancer... and there are various types available... any of them will give satisfactory results, I have yet to see a Dynamic, Mower blade, balancer, rotating looking for a heavy end is still a static single dimension balance system. Like I said some methods of finding a heavy end 'seem' to be more sophisticated than others... but it is still the same single plane principal, just using a different pivot for the same static results...
If you are happy with it, that is the Most important part...
A dynamic balance is Not needed and is impractical to achieve, (for a mower blade)...
For various reasons including those As MBTRAC pointed out...
There Are times when "good enough", is exactly that... good enough. and that is not just a short cut from the possible.... It is achieving a good functional & operational limit.
We are all "usually" mowing with a rotational speed under 4k RPM, static balancing by any method, will be good enough. :smile:KennyV

KennyV said:

There are several ways to use a static balancer... and there are various types available... any of them will give satisfactory results, I have yet to see a Dynamic, Mower blade, balancer, rotating looking for a heavy end is still a static single dimension balance system. Like I said some methods of finding a heavy end 'seem' to be more sophisticated than others... but it is still the same single plane principal, just using a different pivot for the same static results...
If you are happy with it, that is the Most important part...
A dynamic balance is Not needed and is impractical to achieve, (for a mower blade)...
For various reasons including those As MBTRAC pointed out...
There Are times when "good enough", is exactly that... good enough. and that is not just a short cut from the possible.... It is achieving a good functional & operational limit.
We are all "usually" mowing with a rotational speed under 4k RPM, static balancing by any method, will be good enough. :smile:KennyV

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You're right.....:smile:Lawnranger

...and for a different perspective - Until today, I was completely unaware of blade balancing.

I've always just taken the blades off, hand filed til the edge is adequate, and tighten the blade back on the mower.

My little Honda self-propelled 5.5hp is over 15 years old (I can't recall precisely how much over) and never had a perfectly balanced blade except when I installed a new one. Over it's history it's had four blades in total. And, I've used the same method for my 46" lawn tractor with two blades.

Am I advocating using an unbalanced blade?

No, but not having perfectly balanced blades hasn't caused me any problems.

Though, now that I'm aware of balancing blades, I'll see what I can do or not...depends...

Abrahamm said:

...and for a different perspective - Until today, I was completely unaware of blade balancing.

I've always just taken the blades off, hand filed til the edge is adequate, and tighten the blade back on the mower.

My little Honda self-propelled 5.5hp is over 15 years old (I can't recall precisely how much over) and never had a perfectly balanced blade except when I installed a new one. Over it's history it's had four blades in total. And, I've used the same method for my 46" lawn tractor with two blades.

Am I advocating using an unbalanced blade?

No, but not having perfectly balanced blades hasn't caused me any problems.

Though, now that I'm aware of balancing blades, I'll see what I can do or not...depends...

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Crud accumulates at uneven rates on the blades throwing them off. I do note that the three bagger baskets fill better after sharpening and balancing. Guess I'll have to either sharpen or balance next time to see which is having the effect.

I am 74, been cutting grass just about for ever, started cutting with the old Reel type push mower, then after the war, my Dad built our first power mower, had a round metal disk wit 6 mowing machine blades riveted to it, i guess it cur about a 24 in. path, then as years went on i started to sharpen the blades on my different mowers, before the 4 1/2 in grinders came along i used a 7 1/2 grinder, have never to this day tryed to Balmce a Blade, now days i have 2 Mowers, a JD LT 166 & a JD LT 445, the LT 166 was bought in 1999 & the LT 445 was bought in 2000, we use both to take care of about 4 ac. of grass, I changes the Spinal Bearings on the LT 166 when it was 9 years old, and Changed the ones on the LT 445 last winter when i was checking then out while replacing the drive belt, so not messing with trying to Balance the blades dont seem to have effected the mowers very much, This is just this Old Mans View

LakeRat1

PS: i would give just about anything for a Pic. of the mower that my Dad built, the deck was built from wood 2x6s the motor came from our old David Bradly garden tractor, that had tires that looked like Jeep tires, Dad was a Machinist, he build the spinal in side of a pipe, best i can remember it came up above the deck about a ft. had a pulley about 6 in. best i remember, once you crnked the motor, you had to jump the belt on to get the plade turning, the belt had to run with a twist in it, he hung chains down on the back, to knock down anything flying back on the person pushing, I Dont think OSH would allow that today!! LOL

LakeRat1 said:

I...
Balance the blades dont seem to have effected the mowers very much, ...
...

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I have to agree with you, it will not make much of a difference...

I recall seeing more than a few mowers home built, that used wood...
and a twist in the belt was common for reversing engine rotation.... :smile:KennyV

I made a post on the "repair" section of this forum with excerps from a Toro service update school I attended many years ago along with some photos. The post is #5 to #9

http://www.lawnmowerforum.com/small...09-video-series-how-sharpen-mower-blades.html

You can buy a blade balancer off E-Bay 6.95 with shipping. Cheap insurance and very little work to balance a mower blade. I sure can't see why you would not want to clean and balance your blades when you sharpen them. For me its just a once a year job of getting the mower ready for the season.

Lawnranger said:

Actually, the magnetic holder, tapered cone and blade spin on a bearing so in fact it Is a dynamic balancer.

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No, it's still a static balancer (it's what I use.)

A dynamic balancer would detect off-balance conditions at full speed. Conditions such as air flow, inertia, etc. Simular to an automotive wheel balancer. You can static balance a tire, but it may may be out of balance at 38 mph, or 51 mph. (If you notice, they usually balance at 65 mph as any OB is usually not as noticeable at slower speeds.)

One other commenter wrote that it's better than a cheap cone balancer. I completely agree, no matter how careful you are with a cone balancer (which is MILES ahead of a nail or screwdriver balance) it will almost always be out, abet slight, on a magnetic balancer.

You'll get most of the out-of-balance on a code balancer, and it's foolhardy to go through all the trouble in taking the blades off, sharpening and then not take the extra time to balance.

Yes you should balance your mower blades when you sharpen them. But really how perfect can you balance a mower blade. Just look at what they are doing, cutting grass. Now when you cut grass your mower blades are going to build up with old dry grass and be out of balance to a small point anyways. So why would you want to spend big money to get them perfect?

reynoldston said:

Now when you cut grass your mower blades are going to build up with old dry grass and be out of balance to a small point anyways. So why would you want to spend big money to get them perfect?

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Usually the build up you speak of would be uniform from tip to tip on the blade. The whole idea is to balance the blade as best you possibly can.

reynoldston said:

Yes you should balance your mower blades when you sharpen them. But really how perfect can you balance a mower blade. Just look at what they are doing, cutting grass. Now when you cut grass your mower blades are going to build up with old dry grass and be out of balance to a small point anyways. So why would you want to spend big money to get them perfect?

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I agree with Chance123, the blade will accumulate dirt and dried grass, but will continue to stay in balance. Any imbalance would tend to throw the grass off. Sort of like getting snow or ice on the tires of your car. It will only stick if there are no forces trying to throw it off. (Usually).

As for the cost, I bought my balancer 'used' on Ebay, so I didn't pay anywhere near retail. I look at the purchase in the same manner as I would purchasing any infrequently-used tool. (Which is what it actually is).

So your saying if I stuck a wad of gum in each end of the blade the gum would stay there but if only put on one end it would sling off? I hope you are not saying this

Sent from my iPhone using LMF

The force of the blade spinning @ 3600 RPM would throw the gum off of both ends.

Ok so how would the grass stay on the blade the same amount on both ends. As you cut grass the blade does and will not wear even on both ends.
The angle you sharping your blade at is more important than a perfect balance

Sent from my iPhone using LMF

Carscw said:

Ok so how would the grass stay on the blade the same amount on both ends. As you cut grass the blade does and will not wear even on both ends.
The angle you sharping your blade at is more important than a perfect balance

Sent from my iPhone using LMF

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Grass residue is collected over time evenly. You will never see a clump of grass on one end only after it has been running. For the long life of the engine and bearings, balance has priority.
If a blade wore more on one end, it would be way out of balance. The only explaination for your reasoning would be if you hit a rock or sprinkler head and nicked the leading edge on one end of the blade.

Quote "does and will not" I don't understand this. It seems to contradict

Carscw said:

As you cut grass the blade does and will not wear even

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This is where I lost the meaning of your statement

A mower blade, By design will be UNbalanced during operation... The leading edge will be making contact with & cutting grass, that will load that end of the blade... The opposite end of the blade is in an area that has already been cut, or mostly cut. It will have less of a load than the edge that is cutting the bulk of the grass... So you could accurately say that the blade is dynamically Always Very out of balance...
But there will be those that will be Sure that their balancing systems are going to have an effect on this variable state of unbalance... especially if they are using a system that is sold for a lot of $$...
Fortunately balance is Not a very important element in making a lawn mower function & last... :smile:KennyV

KennyV said:

A mower blade, By design will be UNbalanced during operation... The leading edge will be making contact with & cutting grass, that will load that end of the blade... The opposite end of the blade is in an area that has already been cut, or mostly cut. It will have less of a load than the edge that is cutting the bulk of the grass... So you could accurately say that the blade is dynamically Always Very out of balance...
But there will be those that will be Sure that their balancing systems are going to have an effect on this variable state of unbalance... especially if they are using a system that is sold for a lot of $$...
Fortunately balance is Not a very important element in making a lawn mower function & last... :smile:KennyV

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I have to respectfully disagree. A "load" and "balance" are two different issues Just say for example "you are correct in what you say" That would mean if your blade is out of balance to begin with, Once you start cutting, will it be "even more" out of balance? If that's the case it seems best to have the blade as balanced as you can get it to begin with.

An uneven load will impact balance ... a mower blade during its normal operation will always have an uneven load.
The importance of balancing (mower blades) is Greatly overrated. But, as in most things, if it makes you feel better, or pay closer attention to your maintenance procedures ... by all means do it... :smile:KennyV

chance123 said:

This is where I lost the meaning of your statement

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Now your just being a wise ***
Even a child would know it was a type o
As you already know it should have been ( does not or will not )

Showed this to my 11 year old First thing she said was you forgot the not

I am happy for you that you have gone to school for all this How many blades on YOUR mower do you sharping or replace every year?

I have a craftsmen 42 inch mower have cut over 2000 yards with it in the past 2 years have never had to replace a spindle housing or a bearing and we all know how cheap craftsman decks are. I balance my blades on a nail because the star does not sit right on a cone.
If balance was so important I think I would have had to replace something.

I balance my snapper push mower blades the same way as does the snapper dealer I get blades from

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I am seeing when a mower deck spindle bearing gos bad it is because it has no lubrication in it and dirt. I can't ever remember replacing a well lubricated and clean bearing that went bad because of poor balance. Not saying it can't happen but something I never seen. Also I sure can't see no big deal to balance and clean the blade when you sharped it with a cone balance. I just don't see spending big money doing so. I am going to also say that some people will over kill with sharping. As for myself being just a home owner I do it once a year. Also I am not a perfectionist when it comes to mowing or taking care of my lawn.

Very interesting discussion, since the start of this debate I have taken my 21" Honda mulching blade that I normally sharpen with a right-angle grinder to a sharpening service that uses the Magna-Matic equipment (sharpener and blancer) and had it professionally sharpened. The only thing I will say is there was without a doubt a definate difference at full RPM as far as vibration. With that said I admit that I never balanced this blade before with any means but wow what a difference. I was also told that new blades are not balanced and some times are some what out of balance right from the get go. Never the less the balancing sure made my old mower run smother than the day I bought it.

Wow, you guys really get stirred up over balancing, more even than sharpening. First time this forum I've seen a hint of profanity in the "***". :smile:

What we need is a cam corder with strobe video set up under the deck during operation to see what the blades are doing.

Next sharpening I will check the blade balance with dried grass-spinach on blade and them after scraped and wire brushed before sharpening to determine role of debris in static balance. I will use my $2.50 balancer (DIY) to detect imbalance down to 1/8 oz.

If we cannot resolve this issue peacefully here I suggest a BALANCE OFF" contest to be held in Kansas . No beer drinking allowed.:cool2:

motoman said:

Wow, you guys really get stirred up over balancing, more even than sharpening. First time this forum I've seen a hint of profanity in the "***". :smile:

What we need is a cam corder with strobe video set up under the deck during operation to see what the blades are doing.

Next sharpening I will check the blade balance with dried grass-spinach on blade and them after scraped and wire brushed before sharpening to determine role of debris in static balance. I will use my $2.50 balancer (DIY) to detect imbalance down to 1/8 oz.

If we cannot resolve this issue peacefully here I suggest a BALANCE OFF" contest to be held in Kansas . No beer drinking allowed.:cool2:

Click to expand...

I was all set to go to Kansas till you outlawed my beer!

Good afternoon. I have 2 sets of blades for my craftsman and they have the star-shaped center hole. I use a hand grinder to sharpen and use a nail or similar way to check the balance. It is harder with the star shaped hole, but there is ussually 1 spot that is straight up in the 12 0'clock position. I use that one and have had good luck with no vibration from out-of-balance blades. My opinion is that you cant beat the old 20 cents worth of pine board and a 10 or 12 penny nail. I just try to make sure the nail is pounded in far enough to be sturdy and at a 90 degree angle to the board. Why spend up to several $$$ on something when something free or less than 50 cents works just as effective?

marvc, spend another $1.50 and build the diy balancer shown in this forum. it will balance down to 1/8 oz on the star blades.

motoman said:

marvc, spend another $1.50 and build the diy balancer shown in this forum. it will balance down to 1/8 oz on the star blades.

Click to expand...

motoman,

WOW...just read this whole thread and all I can say is I vote for allowing beer at the BALANCE-OFF contest!! The first time I realized that balancing a lawn mower blade was important was right after watching the movie Sling Blade with Billy Bob Thornton:0)
I too began sharpening my lawn tractor blades with the cheap plastic cone balancer. I would use a wire brush, chisel and finally the wire brush on my bench grinder to clean the blade and then balance it as I sharpened it, rotating it on the cone several times to make sure it was good as was possible. I could easily see that this was not a "perfect balancing system"(but of course I didn't know about the less accurate nail method at the time...or the $200 Magna-Matic more accurate balancer). I was one of those that believed the myth that if I didn't do this annually my spindle bearings would be destroyed. But I'm not convinced there is any truth to that. I did, however, notice an improvement in the level of vibration I felt when riding the lawn tractor(or observed/heard in the deck) before/after sharpening & balancing just as mentioned by some other users. Sooooo...even the the cheap diy cone balancers must help "some". I'm still not convince(yet) that it is worth a $200 investment to improve the balancing with a Magna-matic. And I am certain that should I run over someone's head when mowing it's gonna result in a clean & straight cut that would make Billy Bob proud of me:0)

djdicetn said:

motoman,

WOW...just read this whole thread and all I can say is I vote for allowing beer at the BALANCE-OFF contest!! The first time I realized that balancing a lawn mower blade was important was right after watching the movie Sling Blade with Billy Bob Thornton:0)
I too began sharpening my lawn tractor blades with the cheap plastic cone balancer. I would use a wire brush, chisel and finally the wire brush on my bench grinder to clean the blade and then balance it as I sharpened it, rotating it on the cone several times to make sure it was good as was possible. I could easily see that this was not a "perfect balancing system"(but of course I didn't know about the less accurate nail method at the time...or the $200 Magna-Matic more accurate balancer). I was one of those that believed the myth that if I didn't do this annually my spindle bearings would be destroyed. But I'm not convinced there is any truth to that. I did, however, notice an improvement in the level of vibration I felt when riding the lawn tractor(or observed/heard in the deck) before/after sharpening & balancing just as mentioned by some other users. Sooooo...even the the cheap diy cone balancers must help "some". I'm still not convince(yet) that it is worth a $200 investment to improve the balancing with a Magna-matic. And I am certain that should I run over someone's head when mowing it's gonna result in a clean & straight cut that would make Billy Bob proud of me:0)

Click to expand...

dj, if you wanna be like billy bob fix a batch of 'taters and see if the world improves. :licking::licking: motoman

I have a mobile mower maintance business. I use a Dewalt 4 1/2 battery powered grinder to sharpen blades. I always remove blades to sharpen if possible. Generally I balance blades from a single blade mower and unless I see something strange I usually don't balance from a multi-blade mower. I use a plastic cone balancer, I've lost 3 metal ones. So the plastic one meets my needs.

djdicetn said:

motoman,

WOW...just read this whole thread and all I can say is I vote for allowing beer at the BALANCE-OFF contest!! The first time I realized that balancing a lawn mower blade was important was right after watching the movie Sling Blade with Billy Bob Thornton:0)
I too began sharpening my lawn tractor blades with the cheap plastic cone balancer. I would use a wire brush, chisel and finally the wire brush on my bench grinder to clean the blade and then balance it as I sharpened it, rotating it on the cone several times to make sure it was good as was possible. I could easily see that this was not a "perfect balancing system"(but of course I didn't know about the less accurate nail method at the time...or the $200 Magna-Matic more accurate balancer). I was one of those that believed the myth that if I didn't do this annually my spindle bearings would be destroyed. But I'm not convinced there is any truth to that. I did, however, notice an improvement in the level of vibration I felt when riding the lawn tractor(or observed/heard in the deck) before/after sharpening & balancing just as mentioned by some other users. Sooooo...even the the cheap diy cone balancers must help "some". I'm still not convince(yet) that it is worth a $200 investment to improve the balancing with a Magna-matic. And I am certain that should I run over someone's head when mowing it's gonna result in a clean & straight cut that would make Billy Bob proud of me:0)

Click to expand...

You can buy the Tecomec Magnetic blade balancer from amazon for $82.50 and it probably works as well as the Magna Matic. If you want the Magna Matic you can get it on ebay for $179 you can also buy the Oregon BB for $97.00

JDgreen said:

I have been clamping mower blades in a vise to sharpen them with files for over 35 years, really, the only "Balancer" you need is a finish nail driven into a wood block. Just hang the blade on the horizontal nail and if the blade is unbalanced the heavy end will be lower. I have NEVER had an unbalanced blade, because by filing you remove so little material from each end the blade usually remains well balanced.

Click to expand...

While sharpening with a file does remove the least metal, and probably disturbs the balance of the blade the least, you are still changing the blade balance. Using a nail in the wall might get you close, if you have a round hole, and if it is clean, and if you are lucky.

Unfortunately, when we remove metal from the blade, we are changing the dynamic balance, ie left to right,, as well as across the blade. Maybe not much,, but have you priced the cost of replacing the bearing in your mower deck lately?

KennyV said:

An uneven load will impact balance ... a mower blade during its normal operation will always have an uneven load.
The importance of balancing (mower blades) is Greatly overrated. But, as in most things, if it makes you feel better, or pay closer attention to your maintenance procedures ... by all means do it... :smile:KennyV

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Balance of a blade is greatly over- rated.... Let me tell you a story, its not about lawn mower blades,, but it is about balance and the importance of having things balanced.

Several years ago, I was on a trip towing my RV up a pass, the going was slow, and to say the least, I was thinking about getting a smaller trailer.. Everything was fine, until one of the aluminum fan blades separated from the cooling fan. Now one would not think that the loss of a 3 ounce fan blade would have much effect on the balance of a 6.2 L diesel motor would you? When the blade separated, the engine felt for all the world like it would have preferred to be out in the field. I shut down immediately, because I could not imagine what had happened. Of course I was on a tight turn, on the roadway, because there was no shoulder. My wife got out, and walked back along the road and soon returned with the problem, One of the blades from the fan. It could not have weighed over a few ounces. About that time a State police car showed up and inquired about our problem. We told him, and he asked if we could try to reach the top of the grade to where there was a wide spot off the road where we could be safer. I agreed to try, Even at an idle, the engine felt like it was trying to break a motor mount, so as just above an idle, I moved up the grade and off the traveled portion of the road. Now I know that this is an extreme example of the importance of balance, but Balance in anything is important.

WhiteFox said:

...we are changing the dynamic balance, ie left to right,,...

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Sorry, but that would be "static balance. The rotational balance of a mower blade While it is cutting grass is constantly changing effective load, and state of balance. The act of cutting and pushing cut grass off the blade will never be exactly the same from one end of the blade to the other. It Might be close at times, but not the same weight load all the time.

As to the missing fan blade... I'm sure you realize how much you would need to grind off one end of a mower blade to remove 3 ounces of steel... and you will definitely notice that much metal messing from left to right. That amount of asymmetrical you can detect with your unaided eye. The whole point of the balance or no balance "advantage" shows that a nail pivot, as used for decades ... is in fact as useful today as it has been... all with hundreds & thousands of hours operation without failures.
I often just teeter one blade on the sharp edge of another, across the center mounting hole... very accurate, or should I say, Accurate Enough.

This in no way is meant to dissuade anyone from spending more $ on a balance system than they wouldspend on a lifetime of new replacement blades... But if spending More makes you feel it is better... Then that would make it better for you.
:smile:KennyV

For all the DYI people out there balancing a blade is your choice. If you sharpen blades as part of a business, I sure hope you are balancing them. Business owners have to protect themselves at all times. More than one business has had to pay for a new mower, deck, or complete unit, because someone believes that an unbalanced blade was the cause of the failure of their unit. They hire an attorney, and look for compensation. Many times the insurance company or the business owner finds it cheaper to replace the unit than fight the system. All business owners live by a different set of rules. It's called CYA.

kennyv , good discussion. I will shortly report on crud, wear, and balance. which may relate to your analysis.

KennyV said:

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

Click to expand...

Kenny's first sentence is very, VERY true.

I have no doubt whatsoever, that the fancy Magna Matic 1000 (sounds like it should be a Binford model number, huh?) will give a more accurate balance than will a nail. Does that mean that a nail does not give some level of balance? Is the nail balance adequate? In my mind, whether or not the nail balance is adequate is the key question.

I do NOT have the mentality of a salesman, although I sold HMI software for several years in the middle of my career. I was successful only because I knew how to use the product and took care of my customer, not from salesmanship skills. I'm not the salesman that would be selling refrigerators to Eskimo's. From that experience, however, I do understand how zealous one can get about their products and/or technology. I'm sure that Magna Matic is a good company with good people and good products. Where I have my doubts, however, is if the added balance accuracy is REALLY necessary.

If a blade is balanced to the thousandth of a gram, how long does it take to become unbalanced? How much imbalance occurs when in operation? Is that degraded level of imbalance, more imbalanced than a nail balance?

The problem with the analysis of the MagnaMatic balance vs. the nail balance is that we have no quantified data to do actual and meaningful comparisons.

More power to MagnaMatic. They came up with some good ideas and are marketing their products, making profit and jobs. The American way, and I love it, but I would like to see some quantifiable data.

Larry

Is the nail method tested to determine how much imbalance it misses? I looked hard at the "5/8" bolt shank method on the star type hole on my Intek and found it misses 1/2 oz of imbalance. I believe that is due to drag of the bolt shank on the star hole circular ID, and would also miss with non-star center holes. So what? Good question. The Intek V twin sump bolts come loose, but not known if the blade imbalance does it or if it works along with the inherent imbalance of the "harley" V design.
I do know the tractor is much smoother running after balance (down to 1/8 oz.).

Thanks for doing the testing and sharing your results motoman. It's great to see numbers rather than opinions and sales pitch.

Larry

I have had and use a balancer just like a magnamatic since 1992, and have found some blades horribly out of balance. When
I went to work at one of the largest dealers in Louisville, they had one of those little useless cones. I brought mine and mounted
it above my tool box, al of the mechanics would come and check their blades, The M Shop refused to buy one.

They also borrowed my Neway Valve tools, which got old, as those are tools that should be provided by the dealership.

They charged 8$ to reface a valve.

All they did was clamp it in a drill press and hold a piece of sandpaper on it!!!!!!!!!

Fish said:

I have had and use a balancer just like a magnamatic since 1992, and have found some blades horribly out of balance. When
I went to work at one of the largest dealers in Louisville, they had one of those little useless cones. I brought mine and mounted
it above my tool box, al of the mechanics would come and check their blades, The M Shop refused to buy one.

They also borrowed my Neway Valve tools, which got old, as those are tools that should be provided by the dealership.

They charged 8$ to reface a valve.

All they did was clamp it in a drill press and hold a piece of sandpaper on it!!!!!!!!!

Click to expand...

This has been a great discussion, I have been thinking about all you guys have said and had an idea. When I owned a motorcycle I had a motorcycle wheel balancer that consisted of a stand with a steel shaft that sat on roller bearings. There were different sized aluminum cones that fit over the shaft and you would install a cone, slide the shaft through the wheel, install anther cone on the other side and sit the shaft on the roller bearings. I am going to dig that thing out of the shed, clean it up and see if the cones will work on my star hole blades. I'll let you know how it works.

With my MTD blades I can not use the nail way because of how the star sits. And with using the nail you only see what end is heavier you don't know if it is out of balance front to back.

I use a cone that sits on a nail so I can see end to end and front to back I get them as close as I can.

Do a test balance your blades then cut a acre of grass and check the balance do not clean any grass off the blade before you recheck the balance

The only way to get a perfect balance is to have something that tells you where to take some weight off not just take some off anywhere on one end.

(( cowboy up and get over it ))

Well, this whole blade balancing issue has ignited my curiosity. I feel that I have a reasonably good understanding of balance. I have had my own Coats 1001 Computer wheel balancer for over 10 years. I bought it because many of the tire store guys insisted on using weights on the back of my wheels only, not providing a dynamic balance. It came to be one of those "if you want it done right, do it yourself" type things. I understand the difference in a static and dynamic balance on a vehicle wheel.

I can't imagine the economics ever making sense to a point where someone will develop, build and sell a dynamic mower blade balancer, but stranger things have happened.

I have used a nail for probably 40 years or so with acceptable results. Once I saw all the magnamatic discussion, I became quite curious. To begin with, if I were to open a mower service shop, I would have a magnamatic on the wall before I opened the door for business. If I were sharpening blades for hire, I would want to do it efficiently and be able to give my customer the best job I could for their money. I believe that the magnamatic will do that. What I do NOT know is how much more accurate it will balance a blade.

With my curiosity aflame, I took one of the spindles I removed from an old grasshopper deck and disassembled and cleaned everything. With the stiff grease gone, I used two very smooth bearings and oiled them with light, synthetic oil. Synthetic, so that it will not gum up over time. I then mounted the spindle with the shaft horizontal on a support post in my shop. Higher on the same post is a thin finish nail, carefully driven in level.

I put a 21" grasshopper blade on the nail and the left end went down about an inch. I rotated the blade 180 degrees and the right end went down about an inch. I then put the blade on the spindle and one end went down an inch, rotated it 180 degrees and the other end went down an inch.

This was a preliminary test, but it follows the same principles as the magnamatic, a smooth turning, CENTERED mount on the blade.

I will do more testing and will report more results as I learn them. I want to use some wheel weights to try and determine how much weight it takes to balance a blade statically. On a car wheel, you always know just how much weight is required. I will try to make the same determination for the blade balancing.

If I had the coin I would buy a magnamatic so that I could satisfy my curiosity and try to quantify the difference between the balancing methods. It is doubtful that magnamatic would be willing to loan me one for the test.

Will report results as I get it.
Larry

phcaan said:

This has been a great discussion, I have been thinking about all you guys have said and had an idea. When I owned a motorcycle I had a motorcycle wheel balancer that consisted of a stand with a steel shaft that sat on roller bearings. There were different sized aluminum cones that fit over the shaft and you would install a cone, slide the shaft through the wheel, install anther cone on the other side and sit the shaft on the roller bearings. I am going to dig that thing out of the shed, clean it up and see if the cones will work on my star hole blades. I'll let you know how it works.

Click to expand...

Look in this forum for thread "that trick blade balancer cost how much..." It is a wooden version of your motorcycle wheel balancer.

motoman said:

Look in this forum for thread "that trick blade balancer cost how much..." It is a wooden version of your motorcycle wheel balancer.

Click to expand...

Yes I saw that but since I already have the motorcycle balancer I am going to mess with it as soon as I get the time.

I got a few minutes to experiment further with my spindle balancer. I started by using a torpedo level to adjust the face of my spindle to be perfectly plumb. I grabbed a different blade and put it on the nail and it went down on one side about three inches. I put it on the spindle and it went down about the same distance.

I then started grinding off the heavy end and got it level on the nail, even holding up a torpedo level to get it as level as possible. I then put it on the spindle balancer and it was dead level there as well.

I will be hustling tomorrow to catch up so I can take my wife to the doctor on Wednesday, so if I don't get a chance for more testing, I should be able to get back to it on Thursday.

If I were unable to do any further testing, my conclusion or at least what my testing tends to point toward, is that the nail method is worthwhile, and I see why it was actually published in some old John Deere manuals. It is CLEARLY better than no balance at all.

Larry

MBDiagMan said:

I got a few minutes to experiment further with my spindle balancer. I started by using a torpedo level to adjust the face of my spindle to be perfectly plumb. I grabbed a different blade and put it on the nail and it went down on one side about three inches. I put it on the spindle and it went down about the same distance.

I then started grinding off the heavy end and got it level on the nail, even holding up a torpedo level to get it as level as possible. I then put it on the spindle balancer and it was dead level there as well.

I will be hustling tomorrow to catch up so I can take my wife to the doctor on Wednesday, so if I don't get a chance for more testing, I should be able to get back to it on Thursday.

If I were unable to do any further testing, my conclusion or at least what my testing tends to point toward, is that the nail method is worthwhile, and I see why it was actually published in some old John Deere manuals. It is CLEARLY better than no balance at all.

Larry

Click to expand...

Thanks Larry, Keep us posted. When I get a chance to test my motorcycle rig I will post results.

Phil

I got some more time last night and to make a long story short, I balanced a few VERY out of balance blades rather than the not very out of balance blade that I reported on in my last post.

From my experience last night, I now believe that the nail balance is better than nothing, but centering the blade on a ball bearing pivot is MUCH better. My spindle mounted with shaft horizontally makes a good balancer, with MUCH more sensitivity than the nail, but is not nearly as quick and easy to use as the magna matic. The mounted spindle will serve me for now, but when I get the coin, I will be buying a magna matic.

My "balancer." I used two hanger bolts which are hardware items with lag screw threads on one end and machine threads on the other. You probably can't tell from the picture, but the hanger bolts are threaded into a creosote post that is a support in the middle of my hay barn turned into shop. I used two nuts and washers on each stud so that I can adjust them so that the face of the blade mount portion is plumb. I bought a short bolt for mounting the blade so that it wouldn't take as long to mount the blade for test.

Not pretty, but it works great for blades with a center hole that fit. When I do a set of Bad Boy blades, they have a slightly larger hole, so I will try to find something as a bushing to fit them.

Great tool.

Hi folks,

I'm not NEAR the experts that you guys are but I use a scale and a piece of angle iron (in this case a small vise). It's always worked for me.

Sorry but I didn't want to pull my blades off. ;-)

we all have are thing i guess i use a grinder and i don't balance them never broke anything on mine hell i have clients bring me stuff that the blade is worn so bad but u would not know it because it dose not shake ...When u cut grass they go out of balance u chip it its out of balance etc ...The only time it really matters is if u bend the dam thing or take a big nick out of it ...I have been grinding them for 15 years never had a prob yet ..Oh and it depends on what blade u use also if there cheap blades (of shore junk u get what u pay for ):confused2:

I use the gray colored blade balancer that looks like christmas tree to balance mower blades.

davbell22602 said:

I use the gray colored blade balancer that looks like christmas tree to balance mower blades.

Click to expand...

Let's face it, we're all a bit "unbalanced" anyway.

Terry CleanFuel said:

Let's face it, we're all a bit "unbalanced" anyway.

Click to expand...

LMFAO I was going to say that took the words right out of my mouth ...Yes I am a little off balance maybe I should buy one and see if I can balance myself :laughing:

I sharpen with a 4" angle grinder and used to check for balance with one of the cone type balancers.
They were always well balanced so I gave it up. The secret is just don't get carried away with your grinding.

But that was in the old days. Since I started using Gator blades I've found I can go the whole season mowing four acres once a week without sharpening the blades.
They are inexpensive enough that I just replace them at the beginning of the season.

Hi Everybody!

I know, that this bone has been chewed on by so many and so many times that there is no way, that anyone can say anything new about this subject, but I'm reviving this thread because I decided that I'm gonna get an Oregon cone balancer IF it has the right sized diameter rim on it, right for my lawn mover.

So, I was wondering if someone who happen to have an Oregon cone balancer, would you please, measure the diameter of the rims in the approximate range of 19.6 mm (0.77") to see if one of them might be close enough for this diameter? Because if none of the rims of the cone is close enough to 19.6mm, then I wouldn't be able to use it successfully since for e.g. 1mm difference in diameters could throw off the balance.

Geza

Bought a Tecomec blade balancer on ebay (similar to a Magna-matic Mag 1000) after wearing out a spindle bearing and have not regretted it. Have previously tried most methods of blade sharpening; have ended up using a bench belt sander (Ryobi) with a 40 grit paper. At first it was difficult to get a sharp edge with a constant angle, but with a bit of practice it is easy. I have a mulching mower so the blades wear the most about 1 inch from the end of the blade, leaving a curve at this point. As the curve is where the most work is done by the blade, it is this section of the blade that needs the most attention. If I sharpened the blades with a strait cut, the blade would be mainly ground away. I now replace the blades when the wing tips are worn.

Hi Steve,
the balancer you mentioned costs a lot of money from where I stand and since I'm no pro, wouldn't worth it for me. $100 in Hungary means a lot more money than in the US. The Oregon cone balancer is not available in Hungary so I'd order it using E-bay but I don't want to buy it if I couldn't use it and I would have to throw it in the trash. That's why I posted my question of whether if you have one would you measure it for me?

But you said something about not sharpening the blade in a straight line but in a curve of some sort. Could you post a picture of it and also could you post a picture of a blade, that you already trashed (if you still have it somewhere) so we could see what you're talking about?

Géza

Hi Géza,
In my view, people who only maintain their residential yard with a small mower probably do not need to worry too much about blade balancing. If you do buy a balancer, choose the type which best suites you. The cone balancer looks like a cheap and easy method for smaller machines, although I have not tried one. They have steps on the cone so most blades with a central circular hole should fit, and must be a much better option than a nail. Because the blades on my mower are heavy and rotate quickly, balance is far more important than on a smaller machine with a thinner/lighter blade which doesn’t spin as fast. I only bought the Tecomec after much deliberation as it cost me US$130 with postage ($90 + $40); whilst a spindle bearing in Australia cost nearly US$400. Yes, our mower parts and other goods in Australia are much more expensive than in the USA. I will post some photos tomorrow.

Hi Steve,
I totally agree with you on your points. Our Al-Ko classic 38e is 2007 year German made electric (corded) lawn mower with a 38cm (15") long blade and a 1300W (220V), 2800RPM asynchronous motor (no brushes to wear out) used in direct drive (no belt).

Here you can see a few pictures of it: http://pumi.org/geza/temp/browseable/al-ko_classic_3.8e/

We use it around our apartment building on a 1600m2 (1900 yd2) lawn once a month from March through November. I just recently changed the bearings of the motor and the blade holding fan-disk, so so far it looks like it is the right size lawn mower for the task if I had to replace the bearings first time on this 9 year old mower just now.

If you want to buy a new one of the same model today it'd cost you about 150 Euros, I'm not sure about the quality of it though, a lawn mover tech told me recently that the older models are a lot better than the new ones because of the asynchronous motor and direct drive, while the new ones have belt driven blades, cheapo bearing housing, etc.

So, I think you'd consider this lawn mover a smaller unit, it is true, but if or when the blade is out of balance the handle bar can vibrate so badly that it can really bother you plus it can really shorten the life of the motor bearings too. So, this is why I started to care about balancing. The blades are cheap here, around 10 Euros, but I hate to waste and throw them out when it would be time to sharpen them, and since my original trade is auto mechanic, it's no problem for me to mess with this even though it is not mine but belongs to 27 apartment owners. And the owners would kill me if I'd purchase a US$100 worth of balancer for a 150 Euros worth lawn mower.

Photo 1 - Belt sander used for sharpening.
Photo 2 - Worn blade on left showing curve on cutting edge; near new blade on right. If you look closely you can see the differences in the thickness of the wing tips on both blades.

I was surprised when using the Tecomec just how out of balance my old blades were, being previously told by other contractors to use a nail. My local mower shop doesn't even have a blade balancer.

" If you look closely you can see the differences in the thickness of the wing tips on both blades."

I'm not sure what you mean. Maybe you could add some arrow to the photo and post it again?

I just watched a Youtube video on this very same model of sander, it's a nice piece of machinery especially if you consider the price of it too.

Enlargement as requested.

Here I'm quoting your sentence from your very first reply:
" I now replace the blades when the wing tips are worn."

Why do you care about that tip since it is not on the cutting side of the blade but the rear side? If I'm assuming correctly that the cutting side is the right one, it seems to me that way. I don't even see, why that part of the blade gets worn out at all since that is not the cutting side. I must be missing some info here to see this matter clearly.

Because the wins control the air flow under the deck.
The wing ( flute to some ) errodes at the bend then cracks then breaks off and goes flying out at 14,000 ft/ sec.
Good enough reason ?

Electric mowers blades need to have a closer balance tolerance than gas powered, as the shafts and bearing surfaces are smaller and will cause problems with very little vibration.

I know this seems hard to believe, but the wing tips wear out faster than the cutting edge. When the wing tips wear out and break off (dangerous), there is no lift left on the blade so although the mower will cut the grass, it will not mulch leaving obvious grass clippings on the lawn. The first picture shows a line where the grass cuts a groove in the blade (by friction) which then eventually turns into a hole; the tip will then break off, noting the blade is about 6mm thick (1/4 inch). A mulching deck works by lifting the grass back into the deck and re-cutting the grass numerous times. The down side is that the blades wear out a lot quicker than a side discharge mower. The plus side is that there is no grass to dispose of; the mulch is like dust on a dedicated machine/deck so you cannot tell that the lawn has been mulched; and you are not taking anything away from the lawn (nutrients and water). Back to the original thread, from my experience, the higher wear rate on mulching blades means that they need to be sharpened and thus balanced more often than side discharge mowers. The second picture shows the end result.

bertsmobile1 said:

Because the wins control the air flow under the deck.
The wing ( flute to some ) errodes at the bend then cracks then breaks off and goes flying out at 14,000 ft/ sec.
Good enough reason ?

Click to expand...

Thank you for this explanation! I knew, what the rear side and the tip is doing during mowing, I just didn't know how much wear it can cause on that part of the blade.

Rivets said:

Electric mowers blades need to have a closer balance tolerance than gas powered, as the shafts and bearing surfaces are smaller and will cause problems with very little vibration.

Click to expand...

I can imagine, that this is true, for me the vibration of the handle bar that was really annoying and irritating because the frequency of it was similar to what you get from a handheld massage wand, but while you use that only for a few seconds on any part of your body, I had to grab and hold the handle bar of the mower for an hour and that was really uncomfortable, almost painful.

stevestd said:

I know this seems hard to believe, but the wing tips wear out faster than the cutting edge. When the wing tips wear out and break off (dangerous), there is no lift left on the blade so although the mower will cut the grass, it will not mulch leaving obvious grass clippings on the lawn. The first picture shows a line where the grass cuts a groove in the blade (by friction) which then eventually turns into a hole; the tip will then break off, noting the blade is about 6mm thick (1/4 inch). A mulching deck works by lifting the grass back into the deck and re-cutting the grass numerous times. The down side is that the blades wear out a lot quicker than a side discharge mower. The plus side is that there is no grass to dispose of; the mulch is like dust on a dedicated machine/deck so you cannot tell that the lawn has been mulched; and you are not taking anything away from the lawn (nutrients and water). Back to the original thread, from my experience, the higher wear rate on mulching blades means that they need to be sharpened and thus balanced more often than side discharge mowers. The second picture shows the end result.

Click to expand...

Thank you for the tutorial in fine details, now I can see your point. For one, I didn't get it first because the blade on my mower looks completely different and when I was trying to comprehend your previous explanations, it just didn't make sense. You can see a picture of its profile here, It is only a 3 mm thick blade, since I no longer have the old blade, I cannot check any wear that happened to any part of it besides the cutting edge.

Very nice end result!

You mower appears to have a heavy blade with small bearings, so balance is probably more important than many other mowers. I also note that your blade has a lot of metal near the ends, again making balance more critical. It is curious why the cutting edge of the blade appears to be upside down, directing the cut grass downwards not upwards. I am sure there is a good reason for this, but I don’t know what it is. With a slower spin speed and the grass being directed downwards, it is easy to understand why you wouldn’t notice any wear on the wing tips.

Back to your original request, if the slots on the cone balancer don’t exactly fit your blade, why don't you try putting a bit of “Blu Tack” or similar on the cone to help centre the blade.
Better than nothing or a nail in the wall. See the video on this page http://www.lawnmowerforum.com/showthread.php/22507-Where-to-sharpen-blade/page9 . I have also found that new blades can be way out of balance.

Good eye on the blade bevel If you look at the second picture it has the correct bevel. I wonder if it is a china knock off.

The blade weights 390g (14 oz) and the motor has two "6203 2RS" (17x40x12mm) bearings. The blade is an original German design, but the Al-Ko made blades cost a lot more than the ones from the aftermarket.

In Hungary we use blades made by a Hungarian company according to Al-Ko specifications and I've heard that they've turned out to be so good quality that even Al-ko itself put their seal of approval on it and sells it also through its channels.

The only difference between the original Al-ko and the Hungarian blades is that the Hungarian one is made of a tiny bit softer metal than the Al-Ko one, so if you hit a piece of rock with it and it bends, you can easily bend it back in a wise, plus the chances of small pieces flying off of it is less than at the Al-ko blades, plus it is a lot cheaper for the consumers.

About the cutting edge being upside down - it's my "fault", i.e. I happened to take that picture in order to analyze the angle of the cutting edge from close up (25 degrees) and didn't care about how the blade is positioned when it's installed.

I decided to have a custom made ballancer made at a local machine shop, custom meaing, that it will work only with the current blade type with a 19.6mm diameter center hole. It will work exactly as the cone type, except it will be just an inch tall cylinder with a rim on the bottom and the top center of the cylinder inside will have a cone shaped "negative bump" similar to the cone ballancer.

BlazNT: What do you mean on the blade "bevel"?

Bevel/cutting edge. Same thing. Sorry I confused anyone.

Hi Géza,
Just to clarify as it is hard to determine from your previous photo. Is the horizontal plane, or the level/flat part of the blade similar to either line A or B in your previous photo attached (cut and rotated)? I had assumed it was line B which didn’t make any sense. If it is line A, then I can understand why the bevel or cutting edge is on the bottom and the blade would work.

Hi Steve,
Line "A" is in flush with the center (and horizontal) part of the blade.

Later I will post a picture of my new custom designed "cylinder" balancer here.