I was pleased to find this new video from Tormek about convexing sharpening a knife with a T4 Bushcraft. Granted, it could be just as easily done with a T7/8 or a regular T4; however, I have felt the T4 Bushcraft has not received much press.
The video was very well done, both informationally and technically. Here is a link:
https://youtu.be/zqqEyRU2SxY?si=-MOVJymKkkPCObaJ
Ken
Still, this convexing thing is as obscure as ever: there is no explanation whatsoever of why this back-and-forth movement on a convex sharpening medium would end-up producing a convex blade.
A Tormek (and in particular a 200mm one) is intrinsically a bad candidate for convexing a blade. Especially very close to the edge, where the blade will -no matter what - retain the concavity that is the negative image of the wheel.
In addition to that, you don't manage the height over which you shape (for lack of better word) the blade, so it would be quite the miracle if said height matched the blade's original bevel height.
With some of the new jigs, I feel there are some substantial improvements and some which look good for marketing. In my opinion, the substantial improvement in the
KJ-45 jig is the self centering.
Ken
I completely agree on the self-centering feature, with the usual provision that the self-centering feature came at the cost of the adjustable distance.
I think they'd have been better off sticking to their initial position that convexing doesn't matter on a small bevel, and convexing can't be done with a Tormek on large bevels.
And I think it's important that someone who dedicates time reading the forum understands that they won't get belt/backstand-grade convexing with a Tormek.They might not even get much convexing at all.