Anybody Ever Made a Lawnmower Blade?

[Todd Robbins]

Anybody ever made their own lawnmower blade? While abusing my old 20" Walmart pushmower by mowing small bushes,vines, and briars, I managed to mangle the blade. I need another blade, but this mower is evidently obsolete, and a "universal" blade is way more than I want to spend. Does anybody know if all those weird bends and humps and ridges are necessary? I made a replacement blade from 1/16" 15N20 that looks like it'll work great to me, but it's flat as can be. Seems to me like it'll work fine being flat, but I'm curious if anybody else has any experience with this? I just don't know why the original manufacturer would go through the trouble to contour their blade if flat is just as good.

 

[jkf96a]

Seems like I read about Kevin Cashen making some lawnmower blades once. If you do it, try and model the bends/bumps, heat treat it, and draw it back to mid 40's RC.

 

[Coyote Forge]

The blade is pitched like that to create a suction to push the cut grass out from under the mower deck and out the grass chute it also stands the grass up making it easer to cut. 1/16 is way to thin for a blade, needs to be at least 3/16 and soft in the center with just the ends hardened. they are made to bend not break if you hit something. I'd buy one, or at least make the dog and the kids go in the house when you crank that thing up. Also pick you up a new fly wheel key, it sheared when you bent the blade. I'm retired after many years in that buisness, didn't think my first post here would be about lawn mower blades. Take care, Dan

 

[Todd Robbins]

I just mowed for about 2 hours with my self made lawnmower blade. I cut about 1/2 acre of centipede grass and mowed down all sorts of gallberry bushes and assorted vines and such expanding the yard a good bit into the woods. The flat, thin blade worked fine. No bends, cracks, or chips, and it seems to throw the clippings out of the opening a lot better than the original. I ground it cool and left the heat treat the same as it was as a sawblade. I don't know the Rockwell, but it's very springy. I think I will soften the center section with a torch the next time I take it off, just in case, but it worked very well today. Also surprised me with how little the edges deformed from all the crap I ran over with it in the woods. Rather than a cheap replacement for the original, it is actually a noticeable improvement.

I cut a piece out of the original and tested it for hardenability, out of curiosity. It is 1/8" stock, dead soft, and I can't get it to harden at all. Acts like mild steel. Weird...

Thanks for the help, guys.