OT Lawnmower experts. RE blades

[mcdawg22]

My wife bought a Dremel to file the dogs nails down. One night, while having a lot of beverages, I decided to sharpen my machete and hatchet with great results. Is it okay to use on a mulching blade without it messing with the aerodynamics? At which point do I stop and just buy new blades? I have a Honda HRX with dual blade mulching.

 

[RocketDawg]

My wife bought a Dremel to file the dogs nails down. One night, while having a lot of beverages, I decided to sharpen my machete and hatchet with great results. Is it okay to use on a mulching blade without it messing with the aerodynamics? At which point do I stop and just buy new blades? I have a Honda HRX with dual blade mulching.

I also have a Honda mulching mower (walk behind), and use a belt sander to sharpen my blades - clamp it down to a portable work bench and sand away. It works great, only takes a couple minutes, and doesn't change the aerodynamics. I touch it up with a file to remove the burr if needed.

I took my blades to a local shop once to get the blades sharpened, thinking they'd have a jig to put it in for grinding to a factory edge, and when I got them back they looked worse than when I'd used a circular grinder. Turns out they don't have a jig - just do it by hand on a grinder. They charge $25, and you can buy new Honda blades for the same price on Amazon.

To answer your question, the Dremel would probably work OK but would be slower than a best sander, and not as accurate. I sharpen mine two or three times a year.

No matter how you do it, check the balance after you're done so you don't get vibrations (hang it on a nail through the central hole and making sure it hangs level).

 

[MrKotter]

You aren't going to hurt the aerodynamics unless you bend it. Even though it's two blades it really just a mid-high lift blade. A dremel will take a while but I can't see how you'll do any harm. I normally replace blades after they've lost around 1/3 of their width. Angle grinder, belt sander or bench grinder will be much quicker and probably do a better job

 

[garddog]

Best way is with a bench grinder, 8 inch. If you do them often, the angle grinder is fine, but if you have a lot of deformations from rocks the bench grinder works best. You must get them balanced. 90 percent of vibration starts with unbalanced blades which can cause damage to your shaft or bearings.

 

[garddog]

Balancing, if they are round hole, drive a 16 penny nail in the wall next to your grinding area. Hang it and if it tilts it's not balanced. The funky star blades you need a bolt big enough to fit in the middle and almost touch the inner points.

 

[mcdawg22]

Awesome! Thanks all!

 

[Dawgpile]

Echo to reinforce what you've heard already... Balancing. You'll screw your mower in a hurry if the blade is out of balance.

 

[Crazy Cotton]

I went from a bench grinder to a 4" handheld with a flap sanding disk. Takes about 3 minutes per blade to sharpen, doesn't remove as much material as a bench grinder, easier and more maneuverable than a bench grinder, and 4" grinders are cheap as dirt, and quite useful around the house if you get a cutoff blade, concrete blade, etc. Been sharpening them this way for a few decades now and I can stretch a blade out for 4 or five seasons with biweekly sharpening as long as I don't nick the thing too bad.