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Southern Lawns
09-25-2002, 07:55 PM
We talk a lot about the importance of balancing blades after we sharpen. This is how I do it and was wondering if you all do it the same way or what? I sharpen to perfection then balance. Always shaving from the back of the cutting edge so as to never mess the good (sharp) edge up. Just curious on how ya'll do it.
Raymond

Magna-Matic
09-25-2002, 11:29 PM
We recommend that you first check if the blade is bent, to determine first if you should replace the blade.

Next sharpen the blade.

Next check the balance.

Once you have determined the heavy side/end, sharpen more material off of the cutting edge.

______

You do not want to remove material from the END of the blade, this would shorten one end of the blade causing the two tips to be at different dimensions from the center hole.

We have found this to be the most time efficient method to blade service.

It is much easier to balance after you have the sharpening done, because then you will only worry about correcting one side of the blade (the heavy side).

I hope this was of some help,

Thank you,

lawnworker
09-26-2002, 11:11 AM
I have never balenced my blades. They always seem to do fine. maybe I am lucky and am taking off the same on each side. My spindles on my 94 exmark are holding up good. after seven years that speaks alot on exmark quality.

TLS
09-26-2002, 11:32 AM
Originally posted by Southern Lawns
Always shaving from the back of the cutting edge so as to never mess the good (sharp) edge up.

Ray,

I don't know exactly what your saying there, but if its what I think it is....NO thats not a good idea!

Always remove weight when balancing by simply sharpening more on the heavy side. The balance will change quicker when you remove material from the end of the edge rather than in towards the hole.

But taking material off the BOTTOM or BACK of the cutting edge will severely hinder its cutting performance.

Until you get a Magna-Matic balancer, you'll never realize just how far off factory blades can be! I had a set of Exmark blades with the center hole punched 1/8" off center! It wasn't fun correcting these!

MPhillips
09-26-2002, 12:24 PM
I've always gotten an edge then taken material off of the end on the heavy side to balance. I think the loss of cut quality due to having a 'short' side and a 'long' side, is theoretical. I just use one of those little "teepee" balancers too...it appears to get my balance close enough for real world performance. Although I've wondered what level of accuracy is really needed.

Magna-Matic
09-26-2002, 12:40 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,

TLS
09-26-2002, 12:44 PM
Gerd,

I do not think you'll be getting any back! This along with a dedicated blade sharpener have been my best tool purchases in quite some time!

I AM quite the Doubting Thomas. I tried it, and I like. Nuff Said!

Magna-Matic
09-26-2002, 02:47 PM
Well TLS, that is exactly why are confident in our products enough to offer such a TRIAL. How many other companies will accept USED equipment back after 30 days of USE.

We do this with all our products because we know they almost never come back. As soon as you see and use a MAGNA-MATIC product you will experience its quality and performance.

We work very hard to bring lawn care pros the absolute best service tools.

Thank you for the kind words, we do appreciate them!

Westbrooklawn
09-26-2002, 03:11 PM
I am a relatively new owner of both a magna-matic blade balancer and a 9000 sharpener. I am really sold on the balancer...it is very easy to use, extremely accurate, and I can feel the difference in the performance of my mowers (Walker 48" GHS, Lazer Z HP 48, and Toro 44" wb), with properly balanced blades. I would not give up the balancer for anything......well worth the money.

I am still adjusting to the sharpener. I have not been able to get anywhere near the "one minute to sharpen any blade". It does not seem to remove material as quickly as I thought it would. I use to sharpen with a 4.5" angle grinder, and could sharpen a blade pretty quickly without burning.

I still find myself using the angle grinder to remove nicks so that I can get back to a straight plane on the bottom side of the blade, and then using the 9000 to put a finishing edge on. I'm not saying I would give the 9000 up, just that I must need more experience with it........or perhaps some tips on how to use it better. The quality of the machine and the power and adjustments is excellent.

blairbuc
09-26-2002, 03:19 PM
the last question on blade aharpening is the tip. I have heard that most of the cutting is done on the outside corner of the blade. Both tips get rounded with use. Making passes does not get this corner back to 90 deg. I hear a sharp 90 deg. (like when the blade is new) cuts the best. Any suggestions on keeping or getting an old blade tip back from that rounded corner to 90 deg.

TLS
09-26-2002, 03:33 PM
Originally posted by blairbuc
Any suggestions on keeping or getting an old blade tip back from that rounded corner to 90 deg.

Yep....

DONT HIT ANYTHING!!!

Most of the time its due to an impact with a rock or large branch. You try to sharpen this damage out, and in reality, your making your blade length shorter by curving it back. I don't believe there's any way to avoid this.

The ENTIRE blade length will cut, not just the tip. This has been discussed before, WELL discussed. Bottom line, this is why you see more and more mower manufacturers specifying full length sharpened blades.

Magna-Matic
09-26-2002, 06:39 PM
Westbrook, please do call us at 800.328.1110 for some tips on use of the MAG-9000. You shouldn't have any trouble getting the times we advertise. Give a call and we will be happy to explain some things in greater depth.

As far as the TIP and BLADE EDGE go, this as well as the curved cutting edge mulching blades has been a bit of a controversey, about what and what does not cut.

1 - I am sure all of you notice brand new blades have a very strong square TIP.

2 - I am also sure that you have all seen the wear pattern of a blade. The TIP over time becomes rounded, and the rest of the edge is dull/rounded less and less as you go towards the center hole of the blade.

I have heard many opinions on this, some people firmly believe that having an EDGE along the whole blade is great. The only logical reason i have heard for this is, to combat very long grass that would otherwise get wound around the spindle.

This whole debate also addresses whether curved cutting edge mulching blades and blades with longer edges are really effective, or are only a great marketing tactic to sell more mowers, or a new type of blade.

One fact is that the first 1-1/2" of the blade edge does approx 90% of the cutting WORK. Lawnmower blades work off the same principal as a LATHE. This type of cutting is called FREE or FLY CUTTING. If you have ever worked on a lathe, you notice the TIP does all the work.

Unlike a scissors or hedge clippers, that shears against another edge to cut, the mower blade cuts with the speed behind the TIP. This is why MOWER MFGs are concerned with TIP SPEEDS.

I have also heard opinions of MULCHING. Some people say it is all about the proper deck, some believe it is the blade, some think it is the combination, some think true mulching or re-cutting of the grass is not possible without higher TIP SPEEDS and FORWARD CUTTING SPEEDS.

Now, i will always recommend to test everything, and find what has worked best for you. We design our sharpeners so that you are never restricted. In other words, with either of our sharpeners you could put a mile long edge on if you so choose.

But i would invite some of you to perhaps take one of your mowers and make a TEST CASE. Take one mower, and only sharpen the first 2" of the edge and MAKE SURE you re-create that same square TIP. Then run that mower and compare it against your other machines. See if the cut/performance of the mower is any different with a short edge or long edge.

65hoss
09-26-2002, 06:53 PM
Originally posted by MPhillips
I just use one of those little "teepee" balancers too...it appears to get my balance close enough for real world performance. Although I've wondered what level of accuracy is really needed.

I used one of those until I bought the magna balancer at the expo. I was totally surprised at how "off" my blades were. After really balancing them, you can tell it immediately when you turn the blades on. Spin much better and less vibration. Gave back the HP's.

blairbuc
09-26-2002, 07:20 PM
I have the Magnamatic grinder and balancer. My mower is a Hustler Short-Cut 25hp Kohler. I feel the difference when starting the blades at almost idle. Less RPM loss now when balanced. I can't feel the differnce at full rev. but what are you going to feel through 1400 lbs of machine. You would be shocked how some new blades come. You don't know until you have the balancer. If time is an issue just balance the bad ones and leave the close ones alone. But I personally do them all.

Southern Lawns
09-26-2002, 08:01 PM
I don't know exactly what your saying there, but if its what I think it is....NO thats not a good idea!
TLS,
I just make a pass on the blunt side of the heavy end taking off the right amount to set proper balance. I never touch the end of the blade.
Not sure how this effects the performance of the blade. Your not reducing the foil or anything of the blade for that matter. Been doing it for years that way..........But I'm all for learning.
Raymond

Likestomow
09-26-2002, 08:17 PM
I know the Magna Matic balancer is the best. I’ve used one but not owned one. But I have to tell everyone that you can achieve the same perfect results for pennies.

I am referring to the home-made bearing balancer described on Eric Elm’s web page. Here is how I made mine:

1. get two 5/8” O.D. ball bearings --- 1/4” wide with a 1/8” I.D.
2. go to ACE Hardware and buy a 1” nylon spacer and 2 small washers
3. on a 2” - #8 wood screw, place a washer, the two bearings, another washer, and finally the spacer.
4. screw this setup to the edge of a shelve, a board, what ever (I mounted mine just under eye level).

To check the balance, simply mount the blade onto the two bearings (now a ½” wide surface) and hold the blade horizontal. It will either spin or hang there. That’s it – you’re done. If you try this setup you will find it difficult to spend more to achieve the same results.

The only thing this type of balancer won’t do is check for a bent blade, but most of us have a flat surface of some kind to use.

If someone makes one of these, please post your comments.

P.S. I made a second one with 1/2" bearings for my Toro blades.

TLS
09-26-2002, 10:16 PM
While I've never made one of Eric's balancers, I beleive they are far better than a nail in the wall or the cone type, but, I feel they dont come close to a Magna-Matic.

Reason:.... The Magna-Matic takes all size blade holes, pulls them tight against the cone, so you KNOW its centered. Plus it has VERY accurate bearings. If you "make" your own, the bearing quality has too much effect on the accuracy of the tool. Plus if the blade hole is just "slightly" larger than the OD of the bearing, the blade will tilt and give an inaccurate reading.

Granted, his homemade balancer is probably only one or two steps below a Magna-Matic, while a cone is 10 steps and a nail is 50 steps behind!!!!