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Cookin808
03-21-2013, 02:57 AM
Can anyone lead me in the right direction as to some steps and pointers for rounding the spine of a knife.

franzb69
03-21-2013, 03:24 AM
i use a file and sandpaper while the knife is sandwiched between cartons and wood in a vice to keep it stable.

andygraybeal
03-21-2013, 07:30 AM
Would this be the same operation for the choil?

franzb69
03-21-2013, 07:37 AM
yep. you just clamp on it vertically closer inside the vise so you don't bend it too badly. lol.

you make strips of sand paper and make a shoe shining motion around the area you're rounding down and just pull.

stainless is a pain to round down!!!!! lol.

chinacats
03-21-2013, 08:34 AM
I was recently told mill file for spine and saw file for choil...then as Franz said.

Squilliam
03-22-2013, 09:32 AM
I can't recommend using a file on Japanese knife... the file would only be a couple of RHC points above the blade so it won't cut if it's slightly dull, and a sharp file will be quickly dulled. Stick with sandpaper. Stick a 1/4 width strip of duct tape on the back of the paper so it doesn't tear and pretend you're polishing shoes. You will be done before you know it.

franzb69
03-22-2013, 09:42 AM
i just find it to go faster with a file. =D

it was a cheap file so i don't mind wrecking it. i bought it just for that. =D

thanks for the duck tape tip, i'll do just that next time.

Zwiefel
03-22-2013, 12:31 PM
if you don't have a vise available (like me), you can always secure the sandpaper and move the knife across the paper instead of vice versa.

Like this:

http://farm9.staticflickr.com/8460/8064837839_b164857e9b_c.jpg

zitangy
03-22-2013, 01:45 PM
if you don't have a vise available (like me), you can always secure the sandpaper and move the knife across the paper instead of vice versa.

Like this:

http://farm9.staticflickr.com/8460/8064837839_b164857e9b_c.jpg

I do this on a 400grit on a sheet of sandpaper. Spine aroundd 80 degrees to teh sandpaper.

Sometimes I do teh same thing to a stone that needs some serious flattening.. especially at the ends of the stones. Never in teh center of teh stones.

Yes tehre are times when I bring the stones to the spine..

A higher grit after it is smoothed if you want it shiny.

As for the choil..i do it only with a small piece of sandpaper..



have fun

rgds
d

mhlee
03-22-2013, 03:05 PM
I'm almost positive there's a previous thread about this where Dave recommended, IIRC, to first abrade the shoulders. I'm on my phone so I can't quickly search for the thread but I'm sure this has been discussed before.

El Pescador
03-22-2013, 03:40 PM
no vise? use a phonebook or a dictionary.

Zwiefel
03-22-2013, 04:21 PM
no vise? use a phonebook or a dictionary.

I've seen this recco before...but I can't quite imagine how the two fit together for this purpose...anyone have a pic?

Mike9
03-22-2013, 04:51 PM
I find that if the knife is differentially heat treated the spine should be softer than the edge. If it's clad it is softer than the edge. I break the corners with a file or diamond file/plate. Then I back some paper with clear packing tape and slice into strips to polish. You don't need to round to the tip you don't grip down that far and besides your tool will slide right off. When I restore, or do a conversion I like to make the spine as round as possible. The choil area is much harder to achieve a full round finish on.