Bonjour fellow neanderthalians,
I am trying to restore a straight edge on my smoother so blade after they got heavily cambered (0.25-0.5mm) on a deeply hollow brand new trend diamond stone.
Since then, I have tried unsuccessfully to restore a straight edge on these smoothing blades. I am not ultimately shooting for dead straight but a very light camber, which is easy to add on the finest stone, given a straight edge to start from. It is really an infuriating feeling when you can only take a 2cm shaving from a beloved 4 1/2 smoother.
I have a small tormek and a set of good diamond plates (300,600,1200). I usually grind at 25° on the wheel or coarse stone then sharpen and hone at 30° on the other plates, stones and strop, depending on the tool.
I have tried to "start fresh" by placing the blade on my shooting board, and gently shooting it straight with by medium stone. It left me with a blunt edge, similar to a blunt chisel, slightly thicker in the middle. I then ground almost to the edge using the tormek, followed by the stones, with a LN guide, as balanced as possible.
The tormek is not excellent at producing dead square edges by itself, it is all technique from the operator. The stones should be okay, but I have found it hard to fight the "belly" left by the previous camber, in the center of the blade.
To this day, I have not managed to restore the edges to the straightness of my bevel up blades, being left with less than half the cambered I had before. Still kind of heavy.
What would you recommend to correct this? Hone and sharpen the center only until it gets straighter?
NB: I really can’t recommend trend diamond plates, the 300-1000 double sided ones. When I received the first one, I "primed" it using the back of my scrub and fore planes, to remove the eventual loose diamonds and get rid of the fresh aggressiveness. I did not notice at this time it was hollow on both sides as I used it for blades with heavy cambers (say 1 or 2mm). I ordered a new one but returned it as it was also hollow. I tested it at 0.2+mm, which translate to a 0.5mm camber when honing at 30deg.
DMT stones I ordered since are much better it that regard.
Regards from Cro-Magnon rock shelter o/