What went wrong here?

[sharpeknives]

These are the things I would look at just from the pic of the knife. From the top does the knife have a distal taper? If so you are angleing the blade vertically. On a warny you have to keep the edge level. When you set the jig did you do it with the belt on the grinder? I have one of Fred's Jigs it takes alot of practice. Also if you are hogging alot of metal really watch the jig, I set the edge of the bubble on one of the lines. Trying to grind and estimate the bubble on center is a bear. The play in the bubble between the lines can vary 3 or more deg. I'd say try it again. Grind slowly,

 

[Fred.Rowe]

These are the things I would look at just from the pic of the knife. From the top does the knife have a distal taper? If so you are angleing the blade vertically. On a warny you have to keep the edge level. When you set the jig did you do it with the belt on the grinder? I have one of Fred's Jigs it takes alot of practice. Also if you are hogging alot of metal really watch the jig, I set the edge of the bubble on one of the lines. Trying to grind and estimate the bubble on center is a bear. The play in the bubble between the lines can vary 3 or more deg. I'd say try it again. Grind slowly,

I agree with you up until the 3 degree variance in the bubble. There is not that much variance. To prove this to yourself; set the bubble jig on a flat surface and using the 3 degree wedge set the bubble between the lines on the vile; Now go from the 3 degree wedge setting and set the bubble on the 5 degree wedge and see where the bubble goes. It will be at the end of the vile and not between the lines at all. It will squish itself at the end of the vile. If you go from 3 degrees to 3.5 degrees, a 1/2 degree difference in angle of approach the end of the bubble will just touch the line at one end of the vile. A change of a degree and a half will move the bubble to a position where the line at one end of the vile intersects the center of the bubble.
The reason the flats turn out so even using this jig is the ability to place the flat of the blade in the same position each time it is applied to the belt.
If you start the grind using a 5 degree wedge to develop the edge and end up with a 3 degree grind on the bevel; there is a total of 2 degrees in difference of angle of approach in the whole grind so it is unlikely there is a 3 degree variance in the bubble what ever angle of approach you are using.

The ability to hold the bubble steady between the lines does take a bit of practice. But then again learning to master the flat grind no matter what your technique, takes a bit of practice.

Regards, Fred

 

[Phil Dwyer]

I still haven't finished this one.... It's sitting in a drawer right no for no good reason other than some minor flaws. I think I need to go ahead and give it away as I had planned a long time ago.

I'm always looking to help out in any way I can. Let me know if you need my address... :thumbup: