Will a professional please help me with a hollow grind question?

[LARRYZ10]

I have noticed that many hollow ground knives made by professional makers show a nice radius at the top of the plunge line on a hollow grind. It is very noticable on the Loveless drop point hunter for example where the grind goes up the blade and and curves nicely to parallel the top edge of the spine. My hollow grind makes a sharp turn at the top of the grind. Is my grind caused by using a sharp edged contact wheel. I use both a 10 inch and an 8 inch wheel on my KMG. The wheels came from Beaumont metals. Could it be the belts I use are stiff and have no give like a "J-Flex" belt? Could it be that my contact wheels are very hard in Durometer (Sic) or could it be that the wheels have a sharp edge and I am not overlapping the belt on the edge far enough (1/16 inch)? Do some contact wheels have a soft or radiused edge? I noticed that Steve Johnson in his video shows a 3 inch wheel that is radiused somewhat and ground a subhilt fighter with beautiful hollows. Is it a combination of these things or am I doing something wrong with the grind? I am going to watch Johnny Stout's video again tonight and hope to figure this out. I would really like to improve he appearance of my knives and would be grateful for some answers from one of you pros. Thanks, Larry Lehman, Bakersfield, Ca

 

[stezann]

Hi, I'm really not a pro, but i think You've got the point! You made a list of the real reason behind the forming of a nice radius in the upper part of the plunge.
so I'd try firs the ones not compelling to modify your wheels, like flexer belts little more offset...if you have a spare wheel you can chamfer it's sides a bit with a file when rolling...it's up to you since you seem to analyze the subject pretty deep.
Good biting steel

 

[JBS TOOLMAKER]

Larry,
You will need to file a radius on both corners of the wheel. I split an old belt in half to drive it, that will give you plenty of room on each side to move the file around.(always use a handle on your file when doing this) The j-flex belts help to.

 

[David Sharp]

I radiused my wheels and platens. Works very well for me. I used an old Blaze belt to get a smooth radius.

Before you do that though, you may we see if you have success by running a J or J-Flex belt off the edge of the wheel to clean up your plunge and transition. Some swear by this method.