Correct sharpening angle on traditional folders

[Big Papa]

What angle should traditional folders be sharpened at?

Is the angle the same for modern folders like spyderco or benchmade?

Thank you all for your help.

Happy holidays to you all.

 

[Obsessed with Edges]

I've come to believe just about any knife should hold up pretty well, or even excellently, at around ~30° inclusive. If the priority with your traditional knives is for fine slicing, whittling, opening packages & boxes, mail, etc., or other relative light/medium duty tasks, this angle should work fine. Maybe even a little lower, down to around ~25° inclusive or so (woodcarvers seem to like 'em thinner).

If you use your traditional knives very hard (prying, chopping, cutting very tough materials), maybe something around ~35° inclusive might suit you better. Alternatively, you could still sharpen your primary bevel to 30° (maintaining good slicing geometry), and then add a microbevel at 35° for extra durability. I'd never go beyond 40° inclusive, as the wide geometry won't cut well at all, once the apex isn't crisp anymore.


David

 

[KennyB]

With traditional folders the blade stock is so thin that it really depends on what you'll be using it for in my opinion. If you're going to be carving and are going to notice when the edge loses its bite you'll need to pay more attention to wear resistance than if you're just going to be opening letters and boxes and stuff. With a blade with such thin stock as traditional folders usually have, they will cut things quite well even when severely dull. So really in my opinion if this is what you're going to run into, then you should focus on other areas of edge retention such as deformation-resistance. Take the blade down to the lowest angle that it doesn't roll or chip or anything, and I think you'll be pretty happy with it even when it goes "dull".

Following that and OWE's suggestions I would say 17-18 degrees per side to come out with a ~35 degree bevel. You realy won't see any decrease in cutting ability for mundane tasks, and then you'll also have an edge that's robust and won't deform with most of the milder steels used on traditionals.

 

[Jason B.]

Case recommends 10 degrees per side IIRC, that basically means sharpen just high enough to not scratch the side of the blade. The steel is typically softer so sharpening at a low angle on the small thin blades gives the best cutting performance.

 

[KennyB]

Case recommends 10 degrees per side IIRC, that basically means sharpen just high enough to not scratch the side of the blade. The steel is typically softer so sharpening at a low angle on the small thin blades gives the best cutting performance.

Hmm guess you're right ( not to sound surprised lol ) I just looked at my Trapper's manual and they say 10-15

"Hold the blade at a 10 to 15 degree angle from the surface of a sharpening stone. Maintain a constant angle and stroke the blade as if shaving a thin layer from the stone. Repeat the stroking motion along the entire edge of the blade starting at the blade heel and working to the tip. Turn the blade over and repeat the process."

I love how simple they put it

 

[wvdavidr]

Ben Dale (Edge Pro) said in a video that they sharpen most knives at 21 degrees/side. That offers good cutting ability and durability. They'll try to match the factory angle if it's appropriate for the type of knife.

Good sharpening,
Dave

 

[Jason B.]

Ben Dale (Edge Pro) said in a video that they sharpen most knives at 21 degrees/side. That offers good cutting ability and durability. They'll try to match the factory angle if it's appropriate for the type of knife.

Good sharpening,
Dave

That might be good on a big fixed blade but on a small slip joint you'll just end up with a kinda sharp knife that wedges a lot. There is no one size fits all in sharpening.

 

[Obsessed with Edges]

Ben Dale (Edge Pro) said in a video that they sharpen most knives at 21 degrees/side. That offers good cutting ability and durability. They'll try to match the factory angle if it's appropriate for the type of knife.

Good sharpening,
Dave

That might be good on a big fixed blade but on a small slip joint you'll just end up with a kinda sharp knife that wedges a lot. There is no one size fits all in sharpening.

Back in the '90s and before, it seemed like Case's factory edges were in that wide 20°+/side range. I have a lot of Case folders, but avoided buying most of the '90s-dated ones for that reason (had other reasons to avoid them as well). That 'wedging' cutting description is accurate, in how those edges performed. Even if the apex was crisp enough to shave, a lot of those blades tended to bind up in stuff like cardboard, in spite of the thin overall blade grinds. I've also noticed this in a direct comparison between a similarly-ground Queen stockman's blade in D2 and a much larger and thicker blade on a 1965-vintage Case Folding Hunter, with a much shallower edge angle which was also convexed & polished. In cutting cardboard with each, the bigger/thicker Case convexed/polished blade handled the cardboard with ease, but the much thinner Queen's blade, with the wide(ish) but crisply-apexed edge, kept binding in the cardboard.

Cutting really improves when the edge is taken down to 15°/side or less (as Case is doing these days, as is Buck* as well), and more so if the shoulders of the bevels are gently convexed and polished. Turns those blades into laser-beam slicers.

( * = Buck's newer 'Edge2000' grinds are spec'd at 13-16°/side. They arrived at that spec after some extensive CATRA testing, which showed better cutting performance, for a longer time, when maintained in that range. )


David

 

[T. Erdelyi]

...I love how simple they put it

My Old Man used to always say, "...you can always tell when someone's find something right, it always looks easy"

People always say when I free hand sharpen a knife, "...you make it look so easy" what they don't know is the thousands of hours over the years that have gone into practicing.

When it comes to angle I believe as mentioned above the use and size of the blade will determine the correct angle, usually I try to maintain the factory bevel and I can usually tell by the amount of drag on the blade as I push it across the stone if I'm in the range.