Keeping V Edge : Waterstone or Arkansas?

[atod]

Hi Folks,

I'm sure this has been asked many times and I see many posts in the forums regarding this debate. I'm still unsure about what sharpening configuration to use to sharpen my new Ka-Bar BK2.

I would like to keep the V edge and *not* convert it to convex. I see people sharpening for V edge with both Arkansas and Waterstone on Youtube videos.

Does anyone have any pointers on keeping the V edge sharpened? Tools used? The factory edge appears a bit dull.

Thanks

 

[vtvman]

All hand sharpened knives will have a slight convex edge by default due to the variances of us being human. The only way to have a 100% v edge is to use a guided sharpening system like a lansky, gatco, dmt, or wicked edge.

As far as waterstone vs arkansas, I prefer waterstones. They'll both do the job of getting a knife sharp and are just two different solutions to the same problem. Waterstones are less messy imo since Arkansas stones usually use oil and sharpening can become slippery at times.

Is there any reason you don't want a convex edge? They really shine when it comes to an outdoors knife.

 

[atod]

Is there any reason you don't want a convex edge? They really shine when it comes to an outdoors knife.

It was my understanding V edge is a more long lasting edge in the field vs convex which needs more maintenance. Do you know if this statement is true?

Yes, I will be using the knife outdoors, hiking, camping, in woods, etc...

 

[HeavyHanded]

It was my understanding V edge is a more long lasting edge in the field vs convex which needs more maintenance. Do you know if this statement is true?

Yes, I will be using the knife outdoors, hiking, camping, in woods, etc...

As long as the edge geometry is good, there's no large difference between the two. If you have a fairly thick blade, that's when the convex will work noticeably better - much better, not sure what the thickness is of your BK2. Similar results can be had by grinding down the shoulder, in effect creating a convex without worrying about the aesthetics. Any flat stone, be it Arkansas, waterstone, SiC, Aluminum Oxide, diamond etc can be used to maintain a crisp V edge - how crisp depends on individual skill or the use of a guided system. For my camping hatchets and machetes I used to convex with sandpaper, now I just use a V edge and then grind back the shoulder a bit, all on a flat stone. Results are no different in use from what I can tell.

1095 Crovan can be sharpened on just about any type of stone and takes a nice edge. If you're new to sharpening knives, get a couple of cheap ones and practice first before trying to improve your BK2.

 

[Obsessed with Edges]

It was my understanding V edge is a more long lasting edge in the field vs convex which needs more maintenance. Do you know if this statement is true?

Yes, I will be using the knife outdoors, hiking, camping, in woods, etc...

I've found just the opposite to be true. Consider the edges on 'chopping' implements like axes/hatchets, and on higher end heavy knives (like Bark River, Fallkniven) which are usually convex. It adds strength & support behind the cutting edge, and a convex also greatly reduces friction and the effort needed to cut through thicker & tougher materials (this is hugely apparent when cutting cardboard, in particular). Both factors mean less wear & tear on the edge, which increases the edge's cutting life. This is even apparent on smaller, thinner blades, such as on pocketknives. And from a maintenance standpoint, convex seems to me to be the easiest to maintain by simply stropping on leather & compound, or on sandpaper. This is how I maintain all my edges, even when they started out as V-bevels.

The point emphasized by HH, about making sure the edge geometry is good, is all-important. To me, this means making sure the edge is a true 'edge', i.e. fully apexed and sharp. Even a convexed edge should still be essentially a 'V' at the very edge. Otherwise, it'd be too round and blunt. Most of the advantage in convexing is in shaping the steel behind the edge, to add strength and reduce friction.

 

[atod]

I've found just the opposite to be true. Consider the edges on 'chopping' implements like axes/hatchets, and on higher end heavy knives (like Bark River, Fallkniven) which are usually convex.

Can anyone comment on why manufacturers like Becker / Ka-Bar ship the BK2 with a "V" edges and *not* convex? Does it involve manufacturing cost or other factors?

Thanks

 

[Obsessed with Edges]

Can anyone comment on why manufacturers like Becker / Ka-Bar ship the BK2 with a "V" edges and *not* convex? Does it involve manufacturing cost or other factors?

Thanks

I almost commented on that, but omitted it, in my previous posting, as it may be more of a sweeping generalization. But in general, I think the V-edges on most production knives are there because it's easier (faster) for makers to do, with the equipment they use (on the platens of belt grinders). A really good full convex on a blade takes more time, and presumably a more skilled hand to do it right. Especially if the convex is across the full span of the blade, all the way to the cutting edge. Maybe some of the belt grinder guys here can illuminate this a little more.

 

[Benuser]

V-edges are simpler to produce. There could be marketing reasons as well. A very convexed edge will look unsharpened to an ignorant. A V-edge can easily be transformed to a convex one. To transform a convex into a V will imply some loss of material.

 

[Obsessed with Edges]

V-edges are simpler to produce. There could be marketing reasons as well. A very convexed edge will look unsharpened to an ignorant. A V-edge can easily be transformed to a convex one. To transform a convex into a V will imply some loss of material.

Might be something to that, good point. A lot of people (even me) can appreciate the look of a sharp, clean V-bevel on a blade. I've even chosen knives to buy on that criteria, especially when viewing images from online vendors. If the edge bevel looks well-executed, it inspires confidence in the blade being at least decently sharp. Harder to see that on a convex, which can appear deceptively blunt, even when they're anything but.

 

[HeavyHanded]

I almost commented on that, but omitted it, in my previous posting, as it may be more of a sweeping generalization. But in general, I think the V-edges on most production knives are there because it's easier (faster) for makers to do, with the equipment they use (on the platens of belt grinders). A really good full convex on a blade takes more time, and presumably a more skilled hand to do it right. Especially if the convex is across the full span of the blade, all the way to the cutting edge. Maybe some of the belt grinder guys here can illuminate this a little more.

I've converted a couple of thick blades to full convex and it involves a ton of metal removal. Even with a belt sander it took quite a few hours of hard work. I started on one of them just thinning the shoulder, but the stock was so thick, by the time I worked the primary down to a respectable 28-30 degrees inclusive the thing had been transformed into a full convex and almost a full flat grind. I have to imagine if you're set up for it, it wouldn't be that much more difficult than a sabre grind or FFG, most of the stock removal takes place before hardening. Also, even the folks that make their bread and butter doing full convex pooch 'em from time to time, so V bevels might result in a lower 'reject' count.

As I've said, I really do not notice a difference unless the blade has a thick spine (overbuilt "tactical" knives and hatchets primarily) compared to thinning the entire blade face or just hogging some metal off the shoulder. Most knives have way to much bulk to the blade to begin with. Grinding some of this away, whether convex or flat, will make a big difference.

Holy Cow! I just checked the stats for the BK2 and its .25" thick!? That's a prime candidate for a convex, by the time you thin the shoulder out you'll be left with a full convex. Or, you could always leave it as is and it'll work fine, but as it ages you'll still have to bust on the shoulder a bit just to maintain the original geometry. Why do they put a black coating on a hard-use knife?

 

[Benuser]

As an illustration only: one of the best kitchen knives I've got was the Misono Swedish Carbon. Great F&F, great convex edge, highly polished (buffers probably), going from some 10 till 17 degree per side, and the shoulders not removed. It took me just seconds of course - it's a thin knife. I guess it isn't that easy to organise though.

 

[atod]

Thanks Folks. So overall it sounds like this particular knife would be an ideal candidate for convex edge. I have also been recommended that the Waterstone method is preferred over Arkansas. Any suggestions on Waterstones? 1000 + 4000 grit to start with?

Thanks again

 

[David Martin]

Most any man made stone cuts faster than a natural. DM

 

[HeavyHanded]

Thanks Folks. So overall it sounds like this particular knife would be an ideal candidate for convex edge. I have also been recommended that the Waterstone method is preferred over Arkansas. Any suggestions on Waterstones? 1000 + 4000 grit to start with?

Thanks again

You might want to float this over on the Becker forum re convexing your BK2. Doing a full convex is a big job on a knife like that - once started you're committed. Personally I'd run with it as is for a few trips and see how it does.

The Arashiyama waterstones in 1000 and 6000 are highly recommended. I have experience with the Norton and King varieties - both work quite well, the Nortons are faster cutting, the Kings put on a nicer polish. The humble Silicon Carbide stone works well too, and Norton India stones are also a good choice - no need to be restricted to waterstone or Arkansas.

 

[atod]

Most any man made stone cuts faster than a natural. DM

In layman terms, are you saying Waterstone is man made and therefore faster cutting? If so, does this mean it's the better choice?

I see many comments that Waterstone looses it's flush flat surface very quickly and a low spot becomes present in the middle of the stone.

Thanks

 

[Benuser]

For geometry change you may use sandpaper in the P120-600 range.
Yes, waterstones need flattening, some more often than others. Experienced sharpeners may achieve good results with stones that are far from flat, though.

 

[HeavyHanded]

You can go a long way toward keeping the waterstone flat by using the entire surface area. This is a good idea even on a whetstone as it spreads the accumulation of swarf out across the entire area - less chance of it being ground into the pores of the stone requiring extra cleaning and possibly resurfacing. Not to mention it will grind cleaner and faster. Takes a bit of practice, but well worth learning to do.

 

[Alberta Ed]

I switched to diamond (DMT) hones a couple of decades ago and have yet to wear one out. They outlast anything else I've ever used.

 

[Skimo]

There really is very little difference between V and convex, the main difference is user preference. I think the larger issue is keeping the bevels even and achieving an apex.

All stones will dish (lose true flatness) With my cheap SiC stone, I toss some sand on concrete and do figure 8s to get the stone flat again. So stone maintenance really isn't an issue for me. I do the same thing for my edge pro stones.

 

[atod]

Is there any particular stone vendor that stands out? I was considering Smith's TRI6 Tri-Hone for Arkansas and Norton for the Waterstone. Any grit recommendations?

Thanks again for the suggestions