Originally Posted by MacMitch
Ridin, your blade does not look like mine. Maybe yours is for a smaller mower? I think I recall that blades below 21" (for 60 or 61" decks) look more like yours? I checked and I believe this is the Oregon part number we discussed in another post. I checked it several ways on Oregon's site too. I believe my blade and the edge on it are significantly different than yours.
I took a few pictures and put them on Flicker so you can see. I actually angled a bastard file on single edges to abrade as much surface as shows here. I think you can see that the file is not hitting the center of the bevel, indicating that the surface is concave.
The only difference is that mine are for my JD and yours are for a Scag. JD's have the center offset like that to help protect the spindle bolt and spindle from impacts. Mine are 21" long exactly for my 60" deck under my Z950A.
I saw your picture. That is weird because when I run my file across mine (how I sharpen almost all my blades these days), I usually take off metal all the way across the bevel once the coating is worn off. This is with Oregon branded blades, I have others that are slightly hollow ground from the factory, including most of my OEM blades.