Advice for the easing/rounding of spines

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labor of love

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I bet this topic has been discussed in the past but I wasnt too sure how to search for the old threads. Can anybody give some advice for rounding spines DIY style? I heard about using certain metal files for this, does anybody have a file worth recommending? The other technique I once read was to put a knife with the edge facing down in a phone book and just hitting the spine with some coarse sandpaper. Any tips or advice would be very appreciated. Thanks.
 
Labor, I've rounded the spine on at least twenty knives over the years. I don't use any power tools. I'll clamp the handle in a vise. I pad the handle with a silicon hot mitt. Then I knock the 90 degree edges off with a fine metal file. Grind both sides 45 degree angle. Then I'll use wet/dry sandpaper progression with a shoe shine motion to round it to my liking. You really don't need to take off a lot of metal in order to make it comfortable. I guess it depends on how round you want the spine. I polish the entire spine to keep it visually uniform.
 
A few grits of sand paper would work fine. 220 & 400 is good enough, but you could go higher if you wish. Fold it over a few time, or roll into a tube for some stability. That is if you just want to ease the edges. If you want it fully rounded, then it will just take more time, or use a lower grit paper.

Sand paper is all you really need for this. And if you are just easing the edges it only takes a few minutes. I find the choil more difficult than the spine, but if I roll the sandpaper into a tight tube, then I can get into the curve pretty easy.

I got a 1x30 belt sander, so I will throw a 320 grit belt on it for quick easing/rounding and finish off with sand paper, but this is not necessary. I got the belt sander for making handles, not only rounding spines.
 
I start the choil with a round file and then finish with sandpaper.
 
Seriously, 'rounding' choils and spines really is one of the over-rated selling points of more expensive knives, and hyped up a bit too much in my opinion. Nice to have and a lot more comfortable, but dead easy to do yourself in a number of ways.

Knives made for foreign sales from Japan increasingly have the rounding done, by request of foreign sellers who use this as a selling point (justifying higher prices), or because due to this influence buyers request it. However, I'd presume that knives have been sold in Japan for years typically without the coveted rounding because it's pretty much a no-brainer as to how to smooth bits off yourself.

All suggestions above sound fine to me, which shows how reasonable and simple it is to do. I wouldn't make much of it: just some appropriate sandpaper, maybe use natural slurry or powder with that if you want, or other powder, and hold the knife and do it by touch, or secure it somehow, just as you might when restoring kasumi finish on the sides, or at first use stones or other to establish the shape you want, and then use sandpaper or equivalent to complete. Who knows, you've probably just saved yourself at least 50 bucks.
 
Harbor Freight 1x30 belt sander $30.
 
I'm a big fan of this guys' videos, and I feel this one somewhat applies to rounding out spines:

[video=youtube;t6p9kMKs9ok]https://www.youtube.com/watch?v=t6p9kMKs9ok[/video]

You can do the same with a course stone, then sand as he does in the video with finer grit sandpaper. It's really easy to do.
 
Anybody have a particular file they would like to recommend? Preferably something I can buy from Amazon? Thanks for the comments so far.
 
Anybody have a particular file they would like to recommend? Preferably something I can buy from Amazon? Thanks for the comments so far.

Don't have a pic, but I use a cheapie from the hardware store. Don't have it in front of me but guessing the diameter may be about a 1/4" or less. I googled and got this which looks perfect for two dollars.
 
I use a small round file because it is easier to work in the choil area. Flat file will probably work on spine but I usually just use the round file for both. I then wrap sandpaper around a small wooden dowel to finish the process.
 
I use a cheap sharpening stone from a tool shop. Secure the knife in a vice and use the stone as a file. Files also ware down from hardened steel. Then polish with sandpaper progression and chrome polish.
- Kim
 
With the harbor freight 1x30 fully rounded spines are a 3 minute job. Why make it any harder?
 
A vise really helps. These days use Kalamazoo 1X42 to knock down edges. You could use a file. Learned this trick from a forum member. Put duck tape backside of sanding sheet. Do several grits. I cut into 1" strips & use shoe shine motion. You can use the strips over again few times. I still have leftovers made too many done about 20 knives works really well for the polishing stage.
 
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