Rounding choil and spine without a belt sander

[pitted_soul]

Gang,

I have a knife with a forced patina on it. It needs some chamfering/rounding of the choil and spine.

What's the best way to go about this without a bench or belt grinder? I have a dremel, sandpaper, and some moxie.

And if I want to get a forced patina again to cover where I round, do I need to get rid of the old patina first and then reapply, or would it look ok doing new patinas on top of the preexisting? I would think that I would need to get rid of the original and start with a uniform condition so it looks uniform when patinaed but wanted to make sure.

Thanks,

Corey

 

[Troopah_Knives]

It depends a bit on if it is mono-steel or clad. you can round the spine and choil on a clad knife with relatively coarse sandpaper (120 grit or so). With a mono-steel knife, I'd recommend a diamond file. I'd stay away from the Dremel, wheels can dig in quite a bit and are hard to control. It can help a lot if you can clamp the knife down in such a way that you can access the part you are working on without it wobbling around.

 

[M1k3]

Clamp your knife down. A vise works great for this (make sure to protect the blade face from the vise jaws though). Clamping it down also works. Remember the old school shoe shiner's? Use your sandpaper the same way, they would use their towel to shine shoes.

 

[HumbleHomeCook]

If you don't have a vice, you can buy temporary ones that clamp to a table, counter, etc. They can be pretty handy.

 

[Heckel7302]

I put the knife in a vice, use bastard files to ease the corners, then a progression of sandpaper using the shoe shine method

 

[240_Gyutos_Only]

Echoing what other people said, clamp to a vise with adequate clearance around the part you want to round, and shoeshine w/ sandpaper after filing corners. I do this all the time. I would add that I usually cut the strips of sandpaper into thin (~1cm) and long strips, makes them more flexible and easy to tuck into various tight spots. This works with almost any sandpaper too if the strips are made thin enough, not just the really flexible kind.

If you are really good /w a dremel it can save time for removing material, but it risks running away/slipping and causing huge damage easily. I have had that happen to me. Might be easier to do w/ the dremel fixed like a grinder and bringing knife to dremel, but I don't think there is really any need to take the risk w/ dremeling here.

 

[mahwen]

Files if they will cut and sandpaper as others have said. Put a layer of tape across the back of the sandpaper before cutting into strips, will stop them snapping as easily. Also tape up or protect the bevels of the blade as it is easy to leave scuff marks when shoe shining the spine and choil

 

[Martyfish]

Be sure to clamp the blade and protecting it with tape can also be a good idea, depending on how you are working.

If you just want to break the edges or create a small radius, then sandpaper with a shoe shining motion will work fine and not take too long. Doing some of the initial work with a file or even coarse sandpaper wrapped around a dowel can speed thing up, but files can also leave very deep scratches, so beware if you want a more polished finish. Here is a picture of a Victorinox that I rounded without power tools, but the radius is pretty small and it took a long time:

A Dremel can really speed things up, but you need to be careful about removing material evenly and slipping can create problems that totally offset any time saving you have made. Anything you can do with a dremel, you can do with sandpaper, it'll just take longer. Here is a picture of some more serious rounding that i did with a Dremel on my Mazaki nakiri. I did this using a diamond grinding attachment that is marketed as something for trimming dogs nails (see the second picture below) followed by scratch depth reduction using a fine sanding drum and then sandpaper.

 

[dabes]

Here's my Sukenari AS, OOTB every single corner of the knife was a hard right angle, so I hated the in hand feel. Crowned the choil + spine on the dremel w/ medium grit(~1200) sanding drum, there were a few slips near the choil and spine from doing it all freehand.
It was my first time using a dremel for anything, so I found moving the power slider in between 0 and 1 really helped get a good feel for the pressure needed for the desired cutting depth and then moving up from there. Wetting the sanding drum helps w/ control as well.

 

[pitted_soul]

Sorry guys, I was out of pocket for the holidays. I have identified a few knives that I want to do this to and will try tomorrow. I may practice on some cheaper knives and then use the dremel on the real deal. I am in no rush at all. This is a knife that I will be keeping and have already put new pants on but it has some harsh edges that I should have addressed before the handle.

It is Monosteel spicy white. It's pretty spicy too, this might take a minute. Thanks all!!!

 

[HumbleHomeCook]

You might find it is easier than you think. Leave the Dremel for other tasks. Sandpaper around a Sharpie does wonders.

A round file can be handy too.

 

[bradmacmt]

I use a combination of small files, both flat and round (rat tail), and a variety of sandpaper grits (I prefer Emery - wet/dry - papers). For files, think those small ones for chainsaw blades. I'll finish with something like 600 grit emery paper for a final polish. I'd never go near a knife with a dremel, and I'm someone with highly trained, and nimble hands. A Dremel is a catastrophe waiting to happen - those damn things will take off on you quick. One tip - if you're doing a Kasumi finished knife, wrap the entire knife blade in a masking tape right up to the spine/choil, otherwise the micro filings will scratch the knife blade finish. It's takes only 30 minutes or so to do a choil and spine with the above tools. PLEASE do not go near a knife with a Dremel.