Service Request - Rounding Spine and Choil

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Anyone out there that can make quick work of this task? I've asked Jon at JKI but he's hesitant to accept outside knives. I've also used Ryan at District in the past but his work was expensive and less than stellar for what I paid.

Thanks in advance!
 
Do you mind sharing what Ryan charged? That’s kind of wild that he did a subpar job with a 2x72 since it’s like a 5 minute job with a slack belt for the spine and lower wheel for the choil.
 
I remember doing this on a fujiwara FKM, super simple job compared to what most of you all do with the crazy polishing or installing your own handles. Wet/dry sandpaper normally used for automotive stuff. Cut it into strips, put the blade in a vice with some form of soft grips. Apply lube of your choice. I found pulling the strips parallel with the blade face to work best, puts a lot of tension on the paper to keep it taught and focuses the cutting on the corners. Working my way through a few grits took maybe 30 minutes?

Not perfect, so definitely understand finding a crafts person if it’s a presentation or heirloom piece but as a beater knife I was donating to my parents drawer it worked well, but I also don’t really care about scratches from thinning so my taste is dubious at best
 
What's the blade? This is a really, really easy task to perform yourself unless you're looking for a very sculpted easing or very dramatic rounding.
Tanaka AS shinogi and TxK KU, both 240s. I feel like a maker or someone with the right equipment could do this much better than me with sandpaper. I guess I don't know what grits I need because I tried doing this on my TF nashiji 180 and after like 30-45 minutes I didn't make much headway. It's definitely better than from the factory, but nothing like someone experienced could do in a matter of minutes.
 
Do you mind sharing what Ryan charged? That’s kind of wild that he did a subpar job with a 2x72 since it’s like a 5 minute job with a slack belt for the spine and lower wheel for the choil.
I'll echo what has been said about spine/choil work from DC. I asked them to do it for me along with a sharpening order. It was minimal rounding, definitely not a result I'd be happy paying extra for.

I'm curious to see if you guys know of anyone that does good work for reasonable price. I usually do it myself, but it take time, especially with thick square spines. And if I have a batch of knives that need it, I'd rather send that work out to someone who can do it efficiently, and spend my knife time on other stuff like polishing or handlemaking.
 
Using some files or a Dremel to knock off any hard edges and do rough shaping and then following with some decent sand paper & a shoe shine method I have a hard time seeing rounding / polishing taking much longer than boxing up a knife and a roundtrip to ship it.

But if you had a batch of knives that needed work sending it out would make sense to me.
 
For someone who owns no power tools besides a cordless drill and a Dremel, what equipment would work for automating the shoe-shine part?

The image that comes to mind is a sanding belt somehow looped around the tires of an upside-down bicycle, but the picture isn’t very clear.
 
Tanaka AS shinogi and TxK KU, both 240s. I feel like a maker or someone with the right equipment could do this much better than me with sandpaper. I guess I don't know what grits I need because I tried doing this on my TF nashiji 180 and after like 30-45 minutes I didn't make much headway. It's definitely better than from the factory, but nothing like someone experienced could do in a matter of minutes.
I don't know what method you used before, but I have had luck with the "shoe shine" method where you tape and pad the blade and clamp it in a table vise. Then you take strips of sand paper in progressively finer grits and basically act like you're shining a shoe on the choil and/or spine. Hold the strip on either side of the choil or spine and pull the strip back and forth while directing force perpendicular to the axis of the spine or choil.

Kind of like this:

shoeshine.jpg


You don't have to do it at such a wide angle as pictured above. I'd probably bring the ends of the sandpaper strip a little lower.

That said, I no longer live at the property that had a work table with a vise, so the last time I had a spine and choil rounded, it was a knife that I purchased from JKI and I paid for the add-on service. I've tried to do it without a vise by just holding the knife in my hand and it is, shall we say, not enjoyable. Although you may be able to at least ease the spine and choil using a hobby file.
 
Not sure what Jons JKI workload looks like but he did a DT level polishing and rounding job an a knife I bought from him while back.
Think that dude is pretty slammed usually though
 
Monosteel can be a pain, but sanmai would take me longer to pack and ship than to round myself.

I've only used my stones for the spine so far just because they're always handy. I start with either SG220 or nanohone 100DR for the primary work then polish up to 1-4k depending on my mood. The choil I think I used 220 or 320 grit sandpaper wrapped around a sharpie.
 
If you end up trying again yourself:

I would not use a dremel. Too easy for it to get away from you.

Ideally you have something to clamp the knife into so you can use both hands. For gentle rounding wet/dry sandpaper strips work great. I would start around 120 grit and use the shoeshine method. Put a piece of tape on the back of the paper strip to help it last without breaking. Then progress up as high as you like.

For more extreme rounding you need to take a little material off the corners first. A ******* file works great for this. Sandpaper after that.
 
Also cover the blade face if you care about aesthetics, I have been not super careful the last couple of times and got hairline scratches on the blade face. Any sort of tape to prevent the stray scratches, but you gotta use a little alcohol after to remove residue. I would put 1-2 mm off from the spine or choil cause expect to chamfer that amount or or round it

Edit: oh yeah, start at 220 grit, that's worked the best for me. 320 is a bit slower but works, 180 and lower feels like the grains don't cut into iron as well, for 3m sandpaper by hand. I told the paper over or crease it for rigidity. Tape the handle ferrule too! It can wear away a bit. Standing dust can stain stuff like hi wood . . .sometimes I wrap it with plastic wrap. Also yeah. It takes ... About an hour by hand for me. Most of the headway is fine pretty quick but more dramatic tapering etc chamfering rounding ... Takes longer
 
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I’d do it for the hell of it but shipping is pretty pricey.

I usually start with 80 grit if I gotta go from TF style barely chamfered into a full round convex. Feels pretty terrible at low grits but it cleans up quickly. Wrapping a small piece around a chopstick works wonders.
 
For someone who owns no power tools besides a cordless drill and a Dremel, what equipment would work for automating the shoe-shine part?

The image that comes to mind is a sanding belt somehow looped around the tires of an upside-down bicycle, but the picture isn’t very clear.
I feel like it goes without saying that this is dangerous but I'll say it anyway. What I'm about to suggest is dangerous. I use a foam backed automotive sanding pad that attaches to a drill. What I do is lock the drill in the on position, sit in a chair and hold it between my knees with the sanding pad facing up then just go to town being careful to only remove material from the sides and not the top of the spine. Did I mention this is dangerous?
 
For rough knives (think KnifeJapan stuff) I start at 80 grit for the initial shaping. Or 120 for knives with less wabisabi.

I also tape the sides like @refcast mentioned.

Getting the shape right is the slowest step. After that it’s just polishing. And unlike mirror polishing whole blades, you don’t need to do a perfect, scratch-free job, as scratches are less noticeable.
 
I don't have a workbench or vise, but I've found clamping the knife to a kitchen counter (with a foam/rubber layer to prevent scratching) works fine. You have to work at an awkward angle but for one knife at a time it's no biggie. I think I did one with 3M 120 grit to start and then Rhynowet 240 > 400 > 800. Turned out nice. The last one I think I skipped the 120 and 800 and it turned out less pretty but just as comfortable.

Definitely tape the blade face and handle by where you're working, it's so easy to get going and mindlessly slip and scuff it up, especially if the paper suddenly tears. The sandpaper around a pen/chopstick method works okay for the choil/neck transition but is a little awkward. I also used a spray bottle to wet the Rhynowet since I'm working indoors and want to minimize metal dust.
 
Anyone out there that can make quick work of this task? I've asked Jon at JKI but he's hesitant to accept outside knives. I've also used Ryan at District in the past but his work was expensive and less than stellar for what I paid.

Thanks in advance!
happy to do rounding of the spine and choil of other knives... however, if there's significant refinishing or other work like that, we cant take on that kind of time consuming work at the moment. Rounding the spine and choil on its own, however, is no prob.
 
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That’s 12 knives a year. You are a VIP man.
I mean I've only bought one since starting the hobby again last month. 😂Not being able to handle them in person is saving my butt right now, or there'd be a Kagekiyo en route right now!
 
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