I realize there are only 7 of us in the world that use a push mower, but for the other 6 in our small club? THIS is a special day for you. I'm going to show you how to get those mower blades sharp enough to even cut those weird, hard, weedy stems that the mower always misses.
Say hello to my push mower. It's green and red and old. Not olden days old, but old. Floppy disk old.
I knew how to *tighten* the blades on this push mower so they ran across the metal bar properly, but I could never quite figure out how to actually sharpen it.
How to Adjust Your Reel Mower Blades
To move the cutters closer to the bar so your lawn mower makes that cool "click, click, click" sound reminiscent of an episode of Leave it to Beaver, you just have to tighten the blade tightening bolts on either side of the lawn mower.
- Your mower's blades should come as close to the metal bar as possible without actually touching it. Spin the blades (carefully). If you can hear metal scraping they need to be loosened on that end.
- Only turn the bolt a tiny bit to get some clearance.
- There are 4 bolts. 2 that are visible on either side of the reel and 2 on either side of the cutting bar.
- First adjust the bolts (or screws) on the reel. Then adjust the bolts (or screws) on the cutting bar, turning them in the opposite direction that you turned the bolts on the reel.
Easy. Your blades should now be evenly spaced across the whole cutting bar, almost touching it, but not quite.
But sharpening the actual blades is something else entirely. And without sharp blades on your lawnmower, you might as well try cutting your lawn with a sock puppet. You'll get the same results.
And then I found out how to sharpen my lawnmower blades. With a blade sharpening kit.
And angels sang and neighbours joined hands in song.
My lawn would no longer look like a 1980's haircut.
A blade sharpening kit is just some blade sharpening compound and a brush. But it also comes with something very important. A handle that you have to insert into the wheel assembly so you can turn the mower blades over and over again to sharpen them.
To sharpen your push mower you need to take one of the wheels off.
This part might be scary to you; taking your lawn mower apart. But you only partially take it apart. Just a little bit. Barely at all. Just a little off the top.
I know it scares you because it kind of frightened me too. And I don't frighten all that easily. I even got in bed with Jerry Springer once. I have photographic evidence. Which I didn't spend too much time searching for.
I accidentally found this blade sharpening kit at Lee Valley one day when I was wandering around but you can get the same one on Amazon for $14.
O.K. let's sharpen those lawn mower blades!
Before I get to the steps for sharpening, here's a look at the blades before. You can see they're dull.
- Brush the sharpening compound on the edges of all the mower blades.
2. Pop off the plastic cover on the left wheel (the left wheel when you're pushing the mower). It'll just pop off easily.
3. Remove the U Ring. This one's trickier. Don't try to bend it or force it. Just use a screwdriver or knife and stick it under the U ring and gently pry the U ring up. It'll seem like it'll never come off but all of a sudden it'll PING right off and you'll spend the next 10 minutes looking for it.
4. Once the U ring is off you can just lift the whole wheel right off.
5. Under the wheel you'll find the cogged jiggy/jaggy wheel assembly thing. Gently pull it straight up and it will come off.
6. Under the jiggy/jaggy thing is where you'll attach the hand crank that came with your kit. Which is the whole reason you had to remove the wheel.
7. Attach the hand crank and turn, turn, turn in a counter clockwise motion. You'll be going in the opposite direction than how the blades normally turn when you push the mower. For 10 minutes you'll turn.
Then check your blades.
If your blades are evenly shiny and clean looking you're doing a good job. If not, put a little more compound on and keep turning. I had to do it twice and frankly could have done it another time but I got sick of turning.
8. Wipe off any remaining sharpening compound.
After sharpening the blades, put everything back together in the opposite order of how you took it apart.
Then take your mower for a test run. It should be much smoother, with a cleaner cut. Also if you've noticed your grass looks brown on top where you cut it, sharpening and adjusting your lawn mower will stop that.
Maintaining things like your lawn mower, dryer, dishwasher will help them last a lot longer. If I keep this up with my push mower in years I'll be saying "It's old. Not olden days old, but old. The Cloud old."
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Thank you for this article/tips. I'm restoring one form my dad, something to do on quarantine. I now know how to sharppen it. Here in Argentina no such sharpening kit, I will use valve seat paste, I guess is the same. Cross fingers! Keep at home! Cheers
Hi Juan! It is the same thing, it should work well. It's hard to believe people from Argentina to Canada are all under quarantine. Good luck with the mower. :) ~ karen
Hi Juan! I’m trying to sharpen my mower here in Chile, what do you call the paste in Spanish? And where did you find a hand crank?
But how did you get the U-ring back on?? The first time I don’t know how I got it on but this time I’m flummoxed and not happy 😅
Will this work even if the blades are really rusty?
I have 2 Scott's push mowers, I think they are from the 1950's; and one with the wooden handles which is much older. I bought the kit like yours. I find it very satisfying to see the blades all nice and shiny after being sharpened.
If you leave the woodruff key in the shaft and use the proper size socket, you can use an electric drill instead of the crank, as suggested by Garth Wunsch. An ice pick or something equally pointed could help remove the snap ring.
But I think sharpening could be achieved without buying a kit...….just get some valve lapping compound or rubbing compound and a brush. Apply the compound to the blades. Put something heavy to hold the handle to the ground, and grab one of the wheels which now should be in the air. Give the wheel a quick twist to rotate the blade. It would take a little time, but would save the expense of buying a kit.
That would rotate the blade in the wrong direction. The whole idea of removing and fitting a handle, is to turn the blade in the opposite direction to the normal operation. That is why the operation is called back grinding/lapping.
I guess you have never seen electric drills which are REVERSABLE, and can give you the proper rotation when used correctly.
We just just upgraded ours! I had a crappy tire one for years and two years ago attended a "how to sharpen your reel mower" workshop at Lee Valley. During said workshop, I discovered that all reel mowers are not equal and it wasn't all my fault that the mower wasn't working so well! Saved my $ and got one from Lee Valley this year. Wow! What a difference! Who knew we could get so excited over a mower!
Push mowers !!!
My wife and I both have Kawasaki brushcutters and we spend LOTS of time brushcutting!
We don't get the lovely stripes that you used to get with a cylindrical mower though 😕
Just a thought on ring removal, thread a piece of dental floss through one of The holes on ring, then tie ends together an loop on to wrist . When ring pops , ring will not fly away.
Good tip! ~ karen
I’m not understanding how this works...I envision blades spinning without touching anything, and can’t see how the sharpening compound would do anything without some friction or contact of some sort. (Hopefully that makes sense, but clearly I’m not getting something if not.) Karen, can you explain what is happening that actually makes the blades sharper? (I just bought a home with a tiny lot and hope to just use a push mower...so I’m super excited!) Thanks Karen!
I was wondering the same - what do the blades with compound hit to become sharp?
No response, huh? I'm having a problem picturing it, too. I guess it will become clear once I actually try it.
Hi Shannon. The blades do indeed hit the bar on the bottom. That's how the grass is actually cut, when the reel makes contact with the bottom bar. If you don't hear a "click, click, click" sound when you push your mower you might need to adjust the height of that bottom bar to more it closer to the reel blades. All push mowers need this adjustment made the odd time. When it's adjusted properly and the reel is barely hitting the bar on the bottom, when you put the compound on, that friction is what sharpens the blades. ~ karen!
Thank you, Karen!
Karen! Thanks so much for those instructions! Seems like there are more than six of us. I use a riding mower most of the time, but I also have a little push mower I wanted to use to cut up leaves for my compost pile. I didn't know how to sharpen the blades - it's been sitting in my tool shed for 15 years. Yea!
From a Golf Course Superintendent:
This process is called backlapping. It isn't so much sharping the reel as it is honing is against the bedknife (Karen called it a cutting bar). You should still face your bedknife if at all able to. Grinding the top face also is ideal, but you can grind the front face easily without having to remove the bedknife.
At my first good course job when I was a kid, my super was hand filing his greens mower reels. It was tedious work and he couldn't be interupted, as he was counting file strokes per blade. That is how you should sharpen the reel if you can't just take it into your local good course some winter. (FYI: if I had a guy bring one of these into my shop in January, I would bend over backwards to figure out how to get that thing on my grinder and get it dialed in.)
In May 2021 there are no sharpening kits available anyplace! Not on amazon, not even from the companies, and there is no date for possible availability. Very disheartening.
That's understandable. There's a shortage of everything everywhere. I'm assuming things will get back to normal ... when things get back to normal. :) ~ karen!
Lee Valley sells sharpening kit (lapping compound, crank, brush), Canadian tire has valve gringing compound.
Looks like a good tutorial. Reel type is excellent for small areas, or seeding projects where the monster mower will vacuum the seed and mulch. A few things to note:
1. Your local auto parts store will have the paste - it is called Valve Grinding Compound. A hardware store will have the brushes.
2. Day before, soak all the screws, bolts, etc. with either PB Blaster or Deep Creep spray, also available at the auto parts store. Rust loses its will to fight after a few shots.
3. It will vary, but, you may be able to rig a power drill to drive the reel in reverse. You would need an adapter, and extension and socket. Alternatively, if children can be bribed, young muscles work a lot better than old ones to run it long enough to get a good lap on the blades. Ditto for pushing the mower when complete, that task paid for a lot of bubble gum and plastic model paint.
Backlapping produces a bevel angle near 90 degrees. For cutting soft prairie grasses, the bevel angle should be small, say 30 degree or less. Flat and hollow grinding are suitable. The blades should be made of alloy steel (with chromium, vandium, carbon) and hardened to RC60. If lawn grass is quite thick, the gap with bed knife can be opened up to 1-2mm. The reel will rotate at high speed, a naked eye cannot see individual blade.
Thank You for that tutorial. I have a reel mower and I appreciate your information....Mary Harris-Kasuba
I know it can be done! I should say, I knew it 'could' be done, I just didn't know how...Thank you...
You're very welcome Mary! ~ karen!