I'm not sure just how hard the steel is on my mower blades, but I've been touching up the occasional small ding with the mig welder and reshaping the edge. But since the outer edge of the blade does most of the cutting, the outside blades get the brunt of the abuse when mowing along the windbreaks, shrubs. etc. That outer edge will become rounded off a bit. When it's excessive...I've had no problems building that edge back up again with the mig welder without any issues for as long as I've had the mowers.
So far, my blades have never taken a serious hit to where any hint of cracking of the steel has appeared. If the "hit" was that severe.....it would be obvious to check more carefully.
I also use the "ALL AMERICAN SHARPENER" to sharpen the blades and love it. Here's some pics of the blade balancer built from some parts on hand. One day I'll make a better stand for it to lock into. But for now, just clamping it into the vise works great.
The bearings are common roller blade/skate board bearings on a shaft that's attached to that stand by a set screw. The rotating hub is from a chunk of HDPE plastic. The front of the hub has 4 inletted neodymium magnets to hold the blade in place on the front bushing. A few interchangeable front bushing/stubs allows balancing of the different mower blades around here. You can see in the pics a few holes drilled on the perimiter of the black hub to perfectly balance the hub. There's nothing special about the shape of the hub.....it's just what I had available at the time and I made it fit the stub axle with the bearings.
If I want to be overly picky about balancing......the setup is sensitive enough where a couple of squares of toilet paper on the end of the blade will change the rotation. After sharpening, if one side is much heavier than the other.....rather than grinding off material.....I'll tack a bead with the mig on the top outer edge or back side of the lighter end and then adjust the bead with the grinder to re balance. No need to remove more good cutting edge than necessary.
The magnets work slick to hold the blade on and allow for quick changes for balance adjustments. The neighbors can't believe how smooth my 3 pt mower operates. No big secret....just use balanced blades.
Select the thumbnail pics for the full view. Disregard the clutter in the background!!! LOL
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