woodbloke":37kr2rfg said:
If you're familiar with the technique it's not for flattening the backs of old or pitted blades, but will give a couple of mm of polished steel on the back of the blade adjacent to the edge. Whatever sort of blade you have, it's still needs to have the back flattened before honing can begin. The quality of the surface grinding on the back will determine just how much flattening is needed. LN's need very little, LV's need none (they're now lapped anyway) and Record ordinaire need quite a lot :shock: - Rob
Cheers Rob - I got a 60mm iron for my jointer and a replacement for my Record spokeshave, the original blade was so buckled (I guess from the hardening process) I was unable to get the back flat.
In both cases, when I flattened the back, I found that they were both slightly concave. Next to the edge, about 6mm polished up nicely, then I had a rough spot where the metal didnt touch the stone, then I had another polished spot next to the slot. The rough spot doesnt bother me as when the edge eventually gets to that spot I'll be able to polish another 6mm or so.
I would like to know if anyone else has seen this? I think the Ashley Iles chisles are ground slightly concave?
Like I said, they cut really nicely, so Im really pleased! Big difference in honing carbon steel than A2, I much prefer the high carbon blades!
Hmm, Ive just thought - I should probably check the flatness of my oil stones, that could cause this, if they are a little dished then the blades would only touch at the edges...
EDIT: Ive just checked my fine India and my Arkansas stone, they arent dished - must be the blades then!