Rounding the spine with stones

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Delat

Dazed & Confused
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Thought I’d post some pics and vids for those who have it on their list of things to do but haven’t gotten around to it yet. This is the second one I’ve done and it’s pretty quick and easy. I use stones just because they’re handy vs having to dig up sandpaper for the shoeshine method. I started on an SG220 and progressed through SG4000 just because I wanted a polished look.

Here’s the before photo - spine is lightly eased but could definitely use a bit of rounding.
A6A25349-DD37-4675-83ED-22A48688F865.jpeg


And here’s the after shot - you can see I didn’t bother rounding the entire length.
46FBEE8A-9E8B-4102-847D-660298151F77.jpeg


Easy peasy on the stones. I rotate the knife as I’m going back and forth and check frequently to see where needs more attention. Maybe 10-15 mins total on the SG220 but that includes a lot of checking and wiping. This knife is SF100 stainless; somehow I remember my R2 knife going faster on an SG500 (before I bought the SG220) than this one.

edit: Heh, just realized this is a mono and my R2 was clad, so that explains why this one took longer. I see now why bladesmiths hate grinding monos.




One final look after taking it through SG4000. The spine has a nice smooth polish. I didn’t have the patience for full on aggressive rounding, but it’s now very comfortable.

 
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Very nice. This is useful if you (like me) don’t have a vice or anything reliable to keep the knife still when using the shoeshine sandpaper method.

What stones did you use between 220 and 4000?

I’ve heard something like a phone book can work for holding a knife if you don’t have a vice. Presumably you’d have to squash it between your knees to keep it steady.

I went through SG220 / 500 / 1000 / 4000. It’s a subtle difference but we’re all a little nuts about the subtle differences.
 
I did this once to a Henckels chefs knife. Except, I did first 5 passes with a metal file. And then did it on 240/1000 stone and it was done.. Obviously a different price point for a knife, but I was done in about 3-5 min total
 
I did this once to a Henckels chefs knife. Except, I did first 5 passes with a metal file. And then did it on 240/1000 stone and it was done.. Obviously a different price point for a knife, but I was done in about 3-5 min total

Yup, when I rounded off my san-mai knife it went way faster due to the soft cladding even though I started with an SG500. It didn’t occur to me with this knife that I was dealing with monosteel; pretty happy I had the SG220 handy to start with, in retrospect.
 
I personally make knives as a hobby and round off all the knives I make. What I do is lay the spine flat against a belt sander with the belt running the length of the blade rather than across the blade. I start out with a 120 grit belt and then move to a 220 after that. I do the rest by hand by putting the knife into a vise and hand sanding both across the spine and then with the spine at the end to shine in up. It’s really not that hard to do and any belt sander will work.
 
I’ve never done it with stones, but I imagine it goes fast. Really nice to be able to maintain some konosuke-like angles when using a stone for the spine/choil.

60 grit cubitron absolutely tears through iron clad. I’m a big fan of aggressively rounding my own knives where my grip sits. Makes long preps nice and comfy.
 
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