Chunky Tip Permanant Marker Pen

This chunky tipped permanant marker pen is just the job for colouring an edge before you start a sharpening job. 

This can then show you if the angle of approach you are using with your sharpening stone/paddle is correct. 

Too steep and you will just see the ink coming off the edge of the tool, too shallow and you will see the ink coming off around the bevel, and if you have it just right - all the ink will be removed - then keep doing that to sharpen your tool!