Originally Posted by
Euclid440
Jerry, when we do repair work on an edge, a lot of things can happen to the steel and it is not uncommon for it to not take an edge. As said, the damage can be much deeper than what shows visually.
For example, if it had a large chip, and you remove steel to the bottom of the chip, the steel below the chip may be damaged or work hardened and will continue to chip, after a new edge has been formed.
The other issue may be the tools you used to make the repair, low grit aggressive stones or diamond plates can leave deep stria and cause an edge to fail.
If you get a good TNT but it fails, it could be you drew out the fin too long, from too much honing, and it then it breaks off, at the higher grit stones. When I do a lot of edge repairs, I set the bevel, then kill the edge by jointing it on a corner of the 1k stone. Jointing on a stone cuts the fin off straight and not rolling it over as a finger nail or glass would, so you have a straight edge to work with.
Then reset the edge with light pressure on the 1K. Look straight down on the edge to make sure the bevels are fully meeting, with no chipping. If you go to the thread Sean mentioned, Second try at Honing, post 42, page 9, Photos 4 & 5 (upper right hand corner) show and edge that is close, (not fully set). Post 51, page 11, first photo, shows a fully set bevel.
Looking at the edge, straight down will give you a lot more info than a TNT will. You may have to joint and reset an edge a few times to get to good steel.
On that Second try at Honing, fully setting the bevel was a large part of his problem. Once he fully set it, the edge came together fine.