You can easily make a chisel sharpening jig. Take a block of 1" by 4" hardwood board and cut it to 6 inches in length. Cut a 1/4" deep groove in the face of the 4" side at a 25 degree angle, wide enough for the chisel to fit into snuggly. Make a second block in the mirror image of the first one. Join the two ends with 1/4" plywood that have two adjustment slots on one side for different chisel
. width adjustment and attach the ends with pan head screws. Place the block on your sharpening stone and insert the chisel in the 25 degree slot. Slide the jig across the stone to sharpen your chisel. More jigs and instructions can be found here http://www.woodworkingtips.com/etips/etip021004sn.html.
