Help on sharpening blade

Discussion in 'Lawn Mowing' started by adam5557, Apr 25, 2005.

  1. adam5557

    adam5557 LawnSite Member
    Messages: 96

    Hey guys just getting started in the business but have a question and yes i have loooked at a ton of old threads on the site. What would you reccomend for me. I have a exmark 36in metro and i have never sharpened a blade before.What should i buy and any tips on sharpening for a first timer and should i balance the blade and if so what kind of balancer should i buy.Looking for something relatively cheap.Thanks fo the help
  2. joeg2246

    joeg2246 LawnSite Member
    Messages: 169

    I use a 4.5 inch handheld grinder and have a basic cone style balancer. It works for me. I try to angle the grinder at somewhere around a 25 to a 30 degrees. I have priced some actual blade grinders, but, being a part timer I can't justify the expense. I also can't see paying $3.50 a blade to have them sharpened. If you are planning on being in the business full time and attain the number of accounts needed to earn a living. I would definitly invest in a true blade grinder. You will spend around $400 for a decent one, but, it will pay for itself over time.
  3. marko

    marko LawnSite Senior Member
    Messages: 963

    I use a 6" wheel which does a crappy job. I am getting a 4.5" Bosch grinder as stated above as I think this will do a much better job. Some on here use a plain metal file and a vise. Make sure and balance afterwards!
  4. tazz6584

    tazz6584 LawnSite Member
    Messages: 21

    We use a 7 inch disc grinder with a fast removal wheel. This makes it fast and doesnot heat the blade up. which helps with the temper of the blades.We also use a cheap cone type balancer which seems to work well for us.
  5. BigMike

    BigMike LawnSite Member
    Messages: 20

    Here's basically what you need to get a good job everytime...if you already have a table and space to work within, the cost should cost you around $185:

    A Magnamatic balancer---a sealed bearing, wall mounting, precise, blade balancing device that sells for about $100. When I first started I use to utilize the cone to balance my blades; however, I didn't that those little plastic cone balancers were so inaccurate. Once the Magnamatic balancer was purchased, and used, I never once regretted the decision. It will tell on a NEW blade. I gurantee you! I've found, many new blades aren't even balanced...the significance of the unbalance may be minimal, but when you're dealing with an object that spins at 18,000 fps, even the slightest unbalance can hurt performance.

    A basic bench grinder---can be found at Home Depot (~$50). I use a bench grinder everytime to sharpen blades. You have to be careful with basic bench grinders, though...they can destroy blades fast. Like everything, using a bench grinder to sharpen lawn mower blades requires skill, which is aqcuired by hands-on usage (or trial and error). What's required is a slow and steady hand; and, not applying too much pressure on the blade. Another trick is not to get the blade too hot. Put a little oil on the blade edge before grinding to prevent heat damage. Too much heat can damage metal structure...making the blade too soft, which increases the number of times you'd have to resharpen the blade to sustain a sharp edge. After you get the hang of using the bench grinder, you'll be okay.

    A hand file---when using the hand file, stroke the blade in one direction---not back and forth. You're only using the hand file to smooth out the blade edge, and deal with the details of sharpenening. It shouldn't take you much longer than 15-25 strokes per edge. After I'm finished with the hand file, I can run my finger accross the beveled part of the edge, and it always feels smooth--like stainless steel almost.

    My typical order of things:

    1. Clean the blade--scrap off all dirt and debris.
    2. Check balance--take note of heavy side; or, which side falls first on the balancer.
    3. Bench grind--start with the heavy end, and continue to the other side.
    4. Check/Correct balance--lightly use bench grinder to correct balance.
    5. Hand file when balance has been achieved--remember stroke both ends of blade the equally.

    This is how I do it! Hope it helps.
  6. walker-talker

    walker-talker LawnSite Platinum Member
    from Midwest
    Messages: 4,771

    I have used a Lesco (Neary) RBG for the last couple year. Here recently I have gone to the angle grinder for a couple reasons. 1) faster 2) easier to do blades that have bend or curves to them (yes, they come from the factory like this). Blades are cheap enough that I don't really care if I am taking off too much at one time. A good angle grinder might cost around $ least mine did. I bought a Ridgid and it came with a lifetime warranty. New wheels are only a couple buck each.

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