You should hone the whole beveled surface of the chisel and hone the flat side too. It is important to keep the proper angle of the bevel (25 degree). Keep the flat or bottom side flat on your sharpening stone. I use japanese water sharpening stones 220 grit, 600 grit, 1200 grit, 2000 grit, polish it up like chrome, use a leather strop to take the burr off the tip of the chisel after honing on each stone. I use the back side of my leather belt as a strop. You should be able to shave with it or you can slide you chisel over your finger nails with no drag/snagging feel, that is the test of a sharp chisel. I also make a sheath out of scrap manila folders or thin card board to protect the edge of my chisels when transporting them in my tool box. After every job, I do a re-touch-up hone on the chisels that I used.
Jabe, that's what I thought, so I'm not crazy, but apparently my one set of Marples chisels is nowhere near 25 degrees, it's more like 20 degrees, which I find odd.
Keith it is really not all that odd. Realistically you can sharpen the bevel of a chisel anywhere from 20 to 30 degrees depending on what you do with it mostly. For example my Mortising chisels I have ground for a 30 degree bevel as I want more steel behind the bevel to support the edge when using a mallet with them. My everyday set of bench chisels are at 25 degrees but my delicate work only by hand Swiss chisels are at 20 degrees. Now if your bench chisels are at 20 degrees as you say then the edge would be short lived using a mallet with them. So decide what you will do most with them and then grind and hone the bevel accordingly.
In addition to what Jabe and Ken said, you can, if you want, put a micro bevel on the edge. I have, but I'm not yet certain that it is worth the extra effort.
I do put micro bevels on my edges, I'm convinced it's worth the extra effort, as it's easy to get stupid sharp that way. I guess I just never sharpened any of my smaller chisels before and found that the disparity between angles odd. Obviously Ken's right, it doesn't really matter, and the smaller the cutter blade, the smaller the angle seems to make sense, as it can get into tighter places.
Thanks for all the info guys, it's much appreciated.
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