It is hard for some folks to use very machine like straight strokes with a file. You wouldn't want to lug a 12" file in the woods, but for the original Grizzlies, 12" file were the best thing for getting that bevel angle set. For years, with them I followed the directions on the pack with the addition of starting out by flattening the flat side, file the bevel to set angle and build the bur, then with the file flat on the back give it a gentle push flat and forward. The family killed many deer doing that. This thread reminded me of an incident that happened years ago. Tom Mussato used a few more steps with his Hill broadheads than the brochure that Craig put out. At a shooting lanes/archery shop I demonstrated the difference by sharpening a 140 Hill TM style. One recurve shooter that believed those mush tipped Savoras was the only way to go, went on a tirade over it. He held the arrow in his hand and with one continuous motion described how the angle was wrong and how hair and fat would plug it. He said, "See it won't even cut my thumb." Doing that one sweep, to the bone and clear across his thumb. Any archer would have been proud of the blood trail he left as the guys helped him to the back of a pickup to rush him to the hospital.