As to measuring the clearance on setting the reel to bedknife, in my very little experence compared to others I do it by feel, find a point where it barely touches then back it off 1/8 of a turn until you have nil contact.
There is a guy on ebay showing photos with a releif grind, apart from taking a rediculous amount of metal off the reel I cannot see any other point of it, the showed a photo of each edge ground to a point.
