How To Fix a wide bevel and add a choil

[maximus83]

This Bucklite Max 685 is a $25, lightweight, 4" field/hunting blade design by Buck. US-made, comes shaving sharp and great slicing performance, and they've improved the grip. I actually like this thin slicey blade geometry, and the improved grip, better than some more costly FB's I have. Also, this thing has jumped ahead of Moras in my list of favorite low cost FB's. It's a better grip, slices better, and has a full tang blade.

That said, at this price you have to expect some flaws and this knife is no exception.

Two items I'd like to improve/fix on this blade (freehand sharpening input only please , that's how I want to work on this one):

1. Fix uneven bevel. Though the edge is extremely sharp confirmed with sharpening tests, the bevel on the factory grind is crazy wide and uneven on one side, also is inconsistent width at different points, as pictured. The bevel on the other side is half the width of the pictured bevel, and is consistent width from heel tip.
2. Add a real choil. As you can see from the highlighted area, there's ALMOST enough space there to have a real choil. I can rest my index finger there, but really need between 1/8" and 1/4" extra width in the choil. I'd like to go ahead and grind one in there, making the choil both a bit deeper, and wider.

Q's:

• For item (1), what freehand process would you use to fix this, when the difference in bevel width on the 2 sides is double at some points? I realize 'leave it alone' is a live option. But this is something I want to experiment with and it's a common issue with factory grinds, so I probably won't leave it alone.
• For item (2), what steps and abrasives would you use to freehand grind a larger choil in here?

 

[HeavyHanded]

First step is a visual examination to figure out if the blade is warped, then figure out if the edge is pushed to one side of center or is canted off center. Also figure out if the primary hollow grind is uneven, check the plunge line and the shoulders near the tip.

The choil I'd do with a Dremel, or if feeling crafty about it I'd use a coarse DMT tapered rod.

Fixing the bevels you have a choice of grinding the actual edge back a bit and then evening it out, or just even it out and reduce the massive resulting burr as it forms.

Both would be done from the thin bevel side to start and then go back and forth as you get closer. I'd start with my XC DMT. I'd cut the new choil first.

I'm going to have to take a look at one of those.

 

[maximus83]

On the idea of grinding a finger choil into the square highlighted area, I'm reconsidering for a couple reasons. The blade obviously isn't designed for it, so if I cut in an area large enough for a finger, it'll extend into the hollow grind area, which I have to assume will weaken an already pretty thin grind. So, maybe I should skip the finger choil on this one in the interest of preserving the strength of a pretty thin blade.

On fixing the factory bevels, I know you've done a bunch of work with 420HC in the past, and testing it as well. Which kind of abrasive did you find most efficient on 420HC? Obviously my diamond plates will work on anything, but wondering if I might get an even nicer finish off the reprofile if I use SiC and Alox stones.

 

[maximus83]

To experiment, I took an older Bucklite Max and ground a finger choil into it. It wasn't too bad, although I finally had to resort to a Dremel. I wonder how much this weakens the blade? Can't decide if I should do on the newer one pictured in the OP, but it sure does add a degree of fine control when using the blade.

 

[annr]

M maximus83 That looks great! Which dremel attachment(s) did you use, how long did it take, and about how thick is the metal that you removed?

 

[maximus83]

I used a 5/8" AlOx grinding stone. Job took about 15 mins total (incl taping off handle with my gaffer's tape , stopping to check, grinding low speed, and going slow). Blade stock on this one is 0.11" in the primary grind.

 

[annr]

Thanks. So that was 420HC?

I tried this once and it took forever, albeit the taper near the heel of the blade was more 3-D, flaring to maybe 1.75 mm (~1 mm thinner than yours) at the handle.

Did you place it in a vice?

 

[maximus83]

420HC. Placed it edge up in a vise. Thin blade stock + soft steel = easy work.

 

[annr]

Mine was 1 mm thinner, and nothing easy about it! Maybe it is harder— I don’t know.

BUT, it does not seem hard at the edge…who know what it is throughout…it’s some older German-made steel—very good quality IMO.

Thanks for the indirect encouragement to give it another try. I have about 10 of these that could use a “treatment.”

 

[Sonnydaze]

Hey Max...nice work on that choil.

 

[maximus83]

Well here's an update and the finished product. Decided not to take off so much metal just to get the bevels cosmetically perfect, I settled for just getting it super sharp.

* Added a good-sized finger choil.
* Sharpened on 180 grit SiC. This blade is so sharp after that single grit, I just stopped. It easily shaves arm hair and push-cuts all the way through phone book pages.
* Had Robert at Survival Sheath Systems build a sheath and paracord carry rig.

Before:

After: