OK. thanks KO88. Well I can tell immediately that this chisel has never been properly sharpened. I'll get into that later. Your bench grinder is probably a 2950 rpm grinder, and combined with the very coarse looking wheels, you'll probably have some issues. There are ways around that (to some degree).
First off,,, you'll need to regrind the cutting edge, but doing that on the hi-speed grinder will burn your edge. One little trick there. is to hold an ice-cube against the back of the chisel, near the tip as you grind, and be very gentle. Don't try to do it in one single pass,,,, Just "kiss" the wheel, and back off, and repeat until you have a new edge. Don't worry about forming the bevel at this stage. You should end up with a cutting edge that is blunt at this stage, because your only concern at this point, is to "square" the bevel to the side of the chisel. Sharpening the chisel comes later.
Next comes flattening the bottom of the chisel,,,, otherwise called the "back" of the chisel. You do NOT want to flatten the entire back,,,, only about an inch or so behind the bevel,,, but it has to be flattened right to the bevel. You can do this on progressive grades of silicon-carbide wet/dry sandpaper if you wish. Keep polishing until you have a shiny and almost mirror finish,,, or close to that. Just make sure you do this on a very flat surface.
Now, with the back of the chisel flattened, and a new squared edge created, you need to grind off the top of the bevel,,,, not the cutting edge. Grind (or sand) that metal away until you approach what will become the actual cutting edge,,,, but not grinding or sanding completely to that cutting edge. You'll want to leave about a millimeter or two,,,, maybe three mm, so you can create a tiny micro-bevel at the actual cutting edge. At this point, you'll have very little material to remove, and your chisel should be sharper/cleaner than it has ever been, and, you'll have a more durable cutting edge.
In the future, when your chisel starts to get dull again, it'll be very easy and quick to maintain, since you'll only have to re-sharpen the micro-bevel on a good stone, or fine sandpaper. When sharpening the micro-bevel, always repeat that step where you "flatten" the back of the chisel. It'll be very quick and easy to do next time around, because all you're really doing at this point, is knocking off a fine burr at the cutting edge.
Good luck, I hope that helps.
P.S. White abrasive wheels will run cooler than those dark gray Carborundum wheels.
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