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AielLandscaping
09-17-2002, 12:55 AM
for you guys that use angle grinders to sharpen your blades while they are still attached to the mower, how do you know they are balanced? do you take them off and check, or just assume that it's close enough?

Vibe Ray
09-17-2002, 01:54 AM
You use a balancer to tell if it is balanced or not. Now they have cheap ones and expensive ones....so whatever you can afford....you get. Click on the Magna-Matic link on this very page above all these posts (black and white). They have the best balancers of all. They also have sharpeners if you need one (I hear they are some of the best as well).

Phishook
09-17-2002, 02:45 AM
Never heard of sharpening blades while they are still on the mower.

But I take them off and use an angle grinder w/sanding disk. Have never owned a balancer, and never had any vibrations or spindles go bad.---Except the one time I hit a steel rod.

Vibe Ray
09-17-2002, 03:05 AM
Uhhh.....I'm sorry, but I didn't realize you were refering to sharpening the blades while they are still on the mower! As far as that goes, just use a little logic and you'll figure that obviously those who do this would just leave them on and assume that they are balanced because obliously they are trying to save time and because if they took them off after they sharpened them to balance them, why not just take them off first and then sharpen them and then balance them, it would be faster. But if you just sharpened them and assumed they were balanced that would be the quickest way of all.

65hoss
09-17-2002, 11:55 AM
These people probably have the worst set of blades possible. Apparently they need to buy a few more sets of blades. Not to mention the blades ARE NOT BALANCED, but they are destroying the spindles and putting more work on all the working parts of the mower. Everything has to work harder to compensate for the bad blades. If your part-time or full-time in this business your nuts not to have another set of blades with you at all times. You just never know when you might destroy one.

Blades are cheap looking at the entire picture. Blades are the main tool. It doesn't matter how great your mower is, the weakest or strongest link in your quality is the blades. You know a lot about a persons business and maintenance by looking at the blades. Its a Tell-Tell sign!

I've been to look at several "new, going out of business after 1 season" mowers. These people never do any maintenance. They just go mow a few yards and think they've done something. They never change oil and don't even own a grease gun. When I get there to look at this hardly been used gem, when you pull the dipstick it always has very fresh oil in it. Its been washed and cleaned. But guess what? They always forget about the main thing, and I always check it. THE BLADES! It never fails. There is not edge to the blades. They have been hitting the grass with the side of pencils. When I see this I go back to the truck and leave.

scott's turf
09-17-2002, 01:13 PM
Hoss, I am only speaking from my experience. I put on about 15hrs per week on my mowers and usually put on a sharp set of blades dailey and have never ounce sharpened them in over 8 years of mowing. I have yet to replace one spindle. Now maybe this is because I don't put on as many hours as some of you. As a mechanical engineer as well I totally understand the benefits to balanced rotating equipment and preventitive maintenence but I have still yet to see any reprocusions from not balancing. Maybe I am lucky in the spindle dept. too.

thfireman
09-17-2002, 02:59 PM
Quote:
I put on about 15hrs per week on my mowers and usually put on a sharp set of blades dailey and have never ounce sharpened them in over 8 years of mowing.

OK, Maybe I'm just dense and don't understand what you are saying. But are you saying that you put on a new set of blades almost daily and then toss them? If that is what you mean then please start shipping them to me. I will take them off your hands.

If I dont understand then just ignor me cause I must be an idiot!

:D :cool:

nu83
09-17-2002, 03:13 PM
i think he meant he sharpens his blades daily but never (BALANCES?) them.

Gravely_Man
09-17-2002, 04:43 PM
I agree that Scott's Turf meant that he never balances the blades but does in fact sharpen them often.

If someone is going to the trouble of sharpening the blades on the mower and yes it is much harder with them on the mower then off then it is safe to assume they are not going to take them off to balance them. I have heard of this practice. This is not a good idea if you care about your equipment.

scott's turf
09-17-2002, 04:58 PM
I don't throw blades away when they get dull. I meant that I sharpen them and just throw them back on without balancing them and to have yet had any problems. I shapen them with an angle grinder and it takes a couple of minutes/blade max to get a nice edge. There is not a significant amount of off balance weight to cause much vibration. If blades had most of their weight at towards the extents of rotation like car wheels for instance then a little chip off of a blade would cause more vibration. The current spindle designs have higher tolerance which help reduce unwanted movement in the bearings as well. I am not against balancing, I am sure that it prolongs spindle life but I just don't know if we can quantify that. I am on my second engine and second transmission on one of my wb and still the same spindles. The machine doesn't have an hour gage on it but the spidles must have well over 2000 hrs on them.

thfireman
09-17-2002, 06:37 PM
OK, I guess I should have figured that out since everyone else did. Now I understand..
:)

Sammy
09-18-2002, 06:42 AM
I always remove the blades from the deck to sharpen them.

I always use a nail in the wall or a screwdriver to balance the blades.
:)

geogunn
09-18-2002, 10:55 AM
if someone would remove a blade to sharpen it, why wouldn't you want to take a few seconds to balance it?

it's almost too easy to do with the little plastic cone balancer thing.

GEO

scott's turf
09-18-2002, 12:09 PM
Most of those balancing devices, some cones, nail in the wall, etc., don't work because there is too much friction at the pivot for the blade to pivot freely enough. Although I have never balanced a blade it would appear to take a little longer than a few seconds to do it that is unless it is perfectly balanced after the initial sharpening.

65hoss
09-19-2002, 12:23 AM
I use the magna balancer. I used the cone before that and it was not even close. After the initial time, it only takes a few seconds after that.

deason
09-19-2002, 01:51 AM
Origanlly posted by Scott's Turf
There is not a significant amount of off balance weight to cause much vibration.

Obviously sir you have never used a balancer and studied the results. You would not think this way long.

I used to think that putting it on a nail was good enough. I used the Magna Matic this past week on all my sets of blades and was shocked at the results. On some blades it took as long as 20 min to get them to where they would balance.

After balancing all blades and putting them on the mower, I instantly noticed the following -
1) After engagement of the deck at low speed, less load on motor when raised to full throttle.
2) Less vibration in heavy grass. Seems to cut easier

Now, if I can notice this right after I put them on, what else is running better that I cant physically see or hear? I has to be better on ALL moving parts of the machine. Not just spindles.

Magna-Matic
09-25-2002, 01:41 AM
deason hit the nail on the head. As many of you have experienced "Vibration is the root of all evil" in mechanical situations.

Here is a little example. At 70 mph your wheels on your car turn at approx 1000 RPM, your blades turn at approx 3000 RPM. And everyone always balances their wheels and tires. An "out of balance" condition on any rotational part will cause damage on a machine, and consume horsepower.

To address "scott's turf's" comments. You are correct to say that some manufacturers have made spindles heavier to combat unbalanced blades, but vibration will affect the rest of the mower negatively over time as well. The spindles are the most directly affected component. I have heard from some comercial mowers who have had to replace spindles a number of times, and i have also heard from commercial mowers who never replace them. But of course i have no idea how well one the other maintain their equipment.

Please also note that for single blade walk-behind mowers the BLADE is the FLYWHEEL of the motor, and that vibration is being directly applied to the crank shaft.

Scott's Turf please note that the MAG-1000 blade balancer has been in the Outdoor Power Equipment Industry since 1958, and is the standard of the industry. The frictional force of the balancer is only that of the bearings; i.e. almost no frictional force.

The plastic cone has frictional force issues, and the nail in the wall is not gauging from the concentric center point of the blade.

If any one is using the nail in the wall or a screwdriver you are generally causing more harm than good.

Most everyone will notice a significant difference in their mowers after balancing their blades with a MAG-1000. Re-gaining lost HP, extended life of spindles and mower in general. We offer a 30 day money back guarantee if you do not find the balancer satisfactory.

Aside from deason 's testimonial you may want to read a thread from a skeptical lawn care pro who tried our equipment out.

http://www.lawnsite.com/showthread.php?s=&threadid=29793

If anyone has anymore questions i would be glad to answer them.

Thank you,

65hoss
09-25-2002, 09:25 AM
Originally posted by geogunn
if someone would remove a blade to sharpen it, why wouldn't you want to take a few seconds to balance it?

it's almost too easy to do with the little plastic cone balancer thing.

GEO

Hey Geo!:)
Those cone balancers don't work. I was using the cone balancer before I bought the Magna. I thought I was close, but I wasn't. Not even close.
Deason came over to try mine out. I told him how awesome that thing was. He wanted to try it. He was balancing his with a nail before. His were not even close either.
You can feel the difference the moment you turn the blades on.

Darryl G
09-26-2002, 12:39 AM
I don't balance my blades because I don't see why blades would care how much metal is on them but not how much grass and debris is on them. I don't know about all your blades, but mine get all crusted with grass guts, and it's not distributed evenly on them. Do you also scrape the crud off your blades in between sharpenings?

Now, if they are grossly out of balance, I could see there being a difference, but considering that they're going to be out of balance as soon as you start cutting, I don't see the point. If you don't believe me, cut for an hour and pull the blade off and put it on the balancer. I guarantee it will be way off.

Magna-Matic
09-26-2002, 01:32 AM
Darryl it is not so much that the blade cares how much metal is on it, what matters is, the uneven distribution of material (metal) of a part (the blade) whch is in rotation will cause vibration.

Do you get your wheels and tires balanced when you get new tires?

Yes blades should be cleaned between service intervals. Just as you would clean any mechanical part before servicing it.

If you clean your blades between service intervals the amount of grass build up will be minimal. Please note the more steel on one side of the blade versus the other will have a much greater effect than grass. Since steel is heavier than grass.

Many new blades are not balanced, and as soon as a blade is sharpened you have altered the balance. This is why balancing is necessary.

We have tested the balance after cutting for an hour and other time intervals. Our test unit is a KUBOTA diesel F-3060 72" deck, and we mow approx 6 acres. We generally service our blades every 15-20 machine hours.

What greatly affects the balance of the blade is ROCK DAMAGE, SHARPENING, and general wear.

deason
09-26-2002, 01:44 AM
I don't balance my blades because I don't see why blades would care how much metal is on them but not how much grass and debris is on them.

Darryl,

Balancing is for the rest of the machine's benifit, not the blade.

Have you ever had to tighten a nut or replace a cotter pin on your mowers? I bet you have. Do you think the gremlins came by in the middle of the night and loosened the nut or cotter pin? Probably not, but there is only one reason it was loose. VIBRATION. And believe it or not, the small vibes that a blade gives off that is unbalanced is worse on your machine. Over time, this vibration can cause cracks in welds and cause things to "loosen up" that you cant see without looking for them.

An ounce of prevention is worth a pound of parts.
:D

Darryl G
09-26-2002, 01:48 AM
Magna-matic, Thanks for reply. I know that metal weighs more than grass, but I shapen my blades after every 8 or 10 hours of use (with a big file) and get a ton of crud off of them sometimes. Enough that it's got to affect the balance.

You didn't say what the results from your "after cutting" test where. Do you find blades are out of balance after an hour of use?

Darryl G
09-26-2002, 02:05 AM
Deason - O.K., I understand that it's for the machine's benefit, not the blades, but what I don't understand is how you can expect the blade to stay balanced when it gets an uneven layer of crud all over it, especially when cutting wet grass.

Also, the mounting hole in all of my blades is slightly bigger than the bolt, making it possible to install it slightly to one side or the other. Doesn't that throw offf the balance? Again, I just can't see how, given these other factor affecting balance, that it can matter whether your blade is perfectly balanced after shapening.

I sharpen mine with a file and am never taking too much metal off at a time. I used to balance with a nail like my father taught me when I was a wee child, but after hearing it wasn't accurate (here on Lawnsite), I just gave up balancing them entirely.

If I'm just being stupid and putting my equipment I risk, I'd certainly like to know that, but I'm not convinced in the need to spend that kind of money on a state of the art blade balancer.

65hoss
09-26-2002, 06:41 AM
Originally posted by darryl gesner
Now, if they are grossly out of balance, I could see there being a difference, but considering that they're going to be out of balance as soon as you start cutting, I don't see the point. If you don't believe me, cut for an hour and pull the blade off and put it on the balancer. I guarantee it will be way off.

I put my blades on the balancer before I sharpen them to know if they are still balanced. Only 1 out of maybe 7or8 will be a little off. A majority of the blades will still be balanced even with a little grass on them.

Magna-Matic
09-26-2002, 03:33 PM
My recommendation for anyone skeptical about our balancers' cost, accuracy, quality, or practical use is to simply purchase one at our online store for $158.

Try it for 30 days. If you are unhappy with it, or do not feel that it has any benefit to you. Feel free to call us, and ask to return it. We will refund your $158 minus the shipping costs.

This way you can find out for yourself, and your only cost will be the shipping cost if you decide not to keep it.

Thank you,

geogunn
12-11-2002, 04:57 PM
since we are doing the "balancing act" again on another thread that references this thread, I might as well respond to HOSS.



Originally posted by geogunn

if someone would remove a blade to sharpen it, why wouldn't you want to take a few seconds to balance it?

it's almost too easy to do with the little plastic cone balancer thing.

GEO


Originally posted by 65hoss
Hey Geo!:)
Those cone balancers don't work. I was using the cone balancer before I bought the Magna. I thought I was close, but I wasn't. Not even close.
Deason came over to try mine out. I told him how awesome that thing was. He wanted to try it. He was balancing his with a nail before. His were not even close either.
You can feel the difference the moment you turn the blades on.

hoss--you may be right but I don't see it concerning the cone balancer. I know that there are better ways to balance out there but the cone thingey just seems to me would get it close enough to do the job.

now the nail thing doesn't make much sense to me but some people swear by it.

if I wanted to drive eight hours you could show me!:dizzy:

GEO

Magna-Matic
12-11-2002, 05:13 PM
Hello Geo,

Well instead of driving 8 hours, you could just take advantage of our 30 day money back guarrentee.
http://magna-matic.com/Merchant2/merchant.mv?Screen=CTGY&Store_Code=MOS&Category_Code=PBI

The difference between the little plastic cone and a MAGNA-MATIC balancer is night and day.

Its like saying that a craftsman mower is just as good as a commercial mower. Education is the most expensive thing in the world - think about how many things you have purchased in your life that you have now learned do not work.

This is precisely why we offer a 30 day money back guarrentee - any MAGNA-MATIC product can be returned within 30 days for a full refund - less the shipping costs.

How many equipment manufacturers/retailers will offer that - 30 days to USE the equipment - and then be willing to take it back in a USED condition.

Thank you,

geogunn
12-11-2002, 05:55 PM
Originally posted by Magna-Matic
Hello Geo,

Well instead of driving 8 hours, you could just take advantage of our 30 day money back guarrentee.

thanks for the offer.... it sounds like your customers have little to loose when they deal with you and that is the way I like to do buisness!

I am concerned about the cost vs. actual return for the money.

some people don't balance at all and report good results.

people like me try to balance and at least FEEL like we are doing a good job.

and there are the folks that go all out and use a top notch machine like yours.

I'll consider your offer and thanks!:)

GEO

65hoss
12-11-2002, 06:05 PM
Geo, I have the cone balance sitting on the bench, that was what I was using until the magna. Its still there. As stated before, I thought it would be pretty close using the cone, but I found out that is was WAY WAY off. They don't compare. I've got no reason to BS you about it.

Magna-Matic
12-11-2002, 06:06 PM
Hello Geo,

I know that because of the large mix of people online you get many people that do not balance - and do not report problems. Many times these people do not understand the negatives of vibration on mechanical equipment, or they are so used to doing things one way, that they never look for new information or technology.

This post by a very skeptical lawnsite member may be of interest to you. He originally was asking about GRINDER info - but also eventually bought a BALANCER and was very suprised at the results of balanced blades.

http://www.lawnsite.com/showthread.php?s=&threadid=29793

His final test results of our equipment are in the second to last post.

Thank you,

lawnworker
12-11-2002, 07:54 PM
I to am guilty; I never balence my blades. In eight years my Exmark spindles are still doing well. However, I really should get a balencer. I understand the idea behind smooth rotation equals more power. I guess this is a plug for Exmarks' quality older greasable spindles. Why they went to the new type, I will never understand.