Travis, I have done this a couple of times. The most difficult part is keeping the radius uniform along the length of the blade. The other danger point is rolling the edge of the shoulder that seats against the guard. If you roll that edge, it will always look like a gap between the guard and the blade shoulder. So save setting your shoulders until you have finished the radius on the spine.

I would not use a slack belt as this would likely lead to irregular rolling of the edges.

I typically sand the spine down on the 2x72 after the bevels are also at 220. First I take the profile to 220 grit using a work-rest. I keep the ricasso flat on the table so the spine is square to the ricasso. Then I remove the work-rest and working at a slow speed, push the spine against the platen point down. This moves the belt inline with the blade, making the spine straight, and takes out the dips caused by running the belt across the spine.

Once the spine is straight, square, flat, and entirely sanded to 220 on the platen, start to roll the blade to the side and remove the corner. Rock it over the other side and remove the opposite corner. This is still working point down on the platen and produces an even rolled edge along the entire length of the blade. Check the sides and radii for evenness and adjust until you have established the "base" of the radius on both sides.

Now to manual sanding. Take some 320 grit paper and cut 1" strips. Put the blade in a vise edge down, and shoeshine the spine to 320. This is where you start to roll that edge of the shoulder a little, so be careful in that area. You also have to manually adjust the angle of the shoeshine as you work down the distal taper. If you keep the same angle along the entire edge, the radius gets longer down the blade as the blade gets thinner. So don't wrap the paper too tightly. If you aren't making a truly round spine, you will have to run the paper across the top of the spine with almost no angle downward. Take out all of the 220 scratches.

Now take strips of 400 grit paper and a soft sanding block (I use pieces of rubber, 35 durometer, or pencil erasers) and sand all those 320 grit scratches out working inline with the blade. This will also cause a slight rolling of the shoulder, but 400 grit doesn't remove a whole lot of material. Once you have the spine finished to 400 grit, set the shoulders and finish the bevels.

Good luck, and post some pics of your efforts and results!

Joshua,

Thank you for sharing your process in such detail. I greatly appreciate it. I think I'm going to try that on my next knife.

Thanks,

Travis<><