Hi guys, I got a 4V Uguna from Paul of CPE a while back. I had no sharpening experience, and after using the blade to whittle some hardened epoxy, it needed to be sharpened in order to slice paper. Fortunately, the high hardness 4V isn’t easily hogged off, so I’ve been able to learn to hand sharpen on a diamond plate without losing too much steel. With a lot of trial and error, I’ve gotten decent at sharpening and have mostly reprofiled from 20 to 17 degrees. It’s a bit wavy in some spots, but the entire length of the blade is hair shaving sharp, EXCEPT for the tip. Aside from getting a little smoother on the profile, I’d like to get the tip razor sharp as well. Any suggestions on technique would help. Thanks!
-
The BladeForums.com 2024 Traditional Knife is ready to order! See this thread for details: https://www.bladeforums.com/threads/bladeforums-2024-traditional-knife.2003187/
Price is$300$250 ea (shipped within CONUS). If you live outside the US, I will contact you after your order for extra shipping charges.
Order here: https://www.bladeforums.com/help/2024-traditional/ - Order as many as you like, we have plenty.
Sharpening the tip
- Thread starter Teesac81
- Start date
Wowbagger
Gold Member
- Joined
- Sep 20, 2015
- Messages
- 8,006
I would recommend a guided sharpening system . I prefere the old Edge Pro Apex.
That said and when I want to do a quickOdickO job I tend toward Michael Christy's approach . I wear a jeweller's visor (5x to 10X lense)
With this you can look for the gap between edge and stone and close up that gap until you are actually on the edge .
In my view (and that is about fifty years of viewing / sharpening) attempting to maintain an edge angle on a stone to within a tolerance of a fraction of a degree for many many strokes , especially on a curved surface near the point / tip , and taking into account that the factory grind is not going to be the same on both sides (off by a couple of full degrees . . .
what I am saying is : making seriously useful (sharp) edges by hand is silly and a waste of metal .
Fun to fool around with though .
That said and when I want to do a quickOdickO job I tend toward Michael Christy's approach . I wear a jeweller's visor (5x to 10X lense)
With this you can look for the gap between edge and stone and close up that gap until you are actually on the edge .
In my view (and that is about fifty years of viewing / sharpening) attempting to maintain an edge angle on a stone to within a tolerance of a fraction of a degree for many many strokes , especially on a curved surface near the point / tip , and taking into account that the factory grind is not going to be the same on both sides (off by a couple of full degrees . . .
what I am saying is : making seriously useful (sharp) edges by hand is silly and a waste of metal .
Fun to fool around with though .
Last edited:
Wowbagger
Gold Member
- Joined
- Sep 20, 2015
- Messages
- 8,006
PS :
you are not new here , I see , but just a reminder that when you open this part of the forums we are in now : Maintenance , Tinkering and Embellishment
at the top of the page in the Blue area there are a bunch of permanent threads they call "Stickeys" and they contain THE BEST of sharpening advice , from every angle, (sorry couldn't contain my self ) .
Do dive into those when you have a chance .
I would just be regurgitating what they have already recorded .
you are not new here , I see , but just a reminder that when you open this part of the forums we are in now : Maintenance , Tinkering and Embellishment
at the top of the page in the Blue area there are a bunch of permanent threads they call "Stickeys" and they contain THE BEST of sharpening advice , from every angle, (sorry couldn't contain my self ) .
Do dive into those when you have a chance .
I would just be regurgitating what they have already recorded .
Keep the wrist locked, blade at about 45 deg to the stone and any sweep in the blade is handled by raising and lowering the elbow. Use a Sharpie to see where you are removing steel.
It's not complicated and once learned it will save you a lot of time and money over a guided system.
Your getting results, pay your dues with practice.
It's not complicated and once learned it will save you a lot of time and money over a guided system.
Your getting results, pay your dues with practice.
- Joined
- Apr 12, 2009
- Messages
- 13,432
The upsweeping belly and tip of the edge are sometimes ground at a much wider angle than in portions aft of the belly. This is usually because an upswept grind to the tip will be further into thicker steel nearer to the spine of the blade, assuming a tapered grind from a thicker spine down to a thin edge, as most blades will be. In an effort to make the edge bevels appear uniform in width along the full length of the edge grind, a wider factory edge angle is necessary in the thicker portions nearer to the spine. If the grinding angle were held exactly the same along the full length, the portions in the thicker steel will have noticeably wider bevels, which wouldn't look as attractive to most buyers.
All the above is to say: You might have to lift the handle more than just a little, and maybe a LOT, when getting into the belly and tip of the blade. The Sharpie method can help you see how much you need to lift the handle when grinding near the tip. Darken the edge bevel with a Sharpie pen. Then see where the ink comes off when you're grinding the bevel on the stone. Near the tip, you might notice the ink only coming off at or above the shoulder of the edge bevel, and not at the edge itself, because the edge angle there is probably much wider (more obtuse). For a visual training aid, I'd also suggest just holding different sections of the edge bevel flush and still against a flat & smooth surface like glass, and inspecting closely with a magnifier to see if the edge in that portion is making contact with the smooth surface. That'll open your eyes as to how much you might have to increase the held angle (by lifting the handle) against the stone when sharpening in different portions of the edge grind. Also keep in mind, because the held angle likely needs to be wider near the tip, the cutting performance of the fully apexed tip still won't compare to sharpness in the further aft portions, because the edge geometry is wider near the tip.
Alternatively, you could also just keep grinding at a consistent lower angle all the way to the tip. That will help you attain hair-shaving sharpness all the way out to the tip. Assuming the steel near the tip is thicker, it'll take much more time to apex the edge near the tip. Keep inspecting the edge under magnification as you go, to make sure you fully apex the edge near the tip. And the edge bevel approaching the tip will widen considerably as compared to the bevel width further back along the edge. For myself, I generally prefer edge thinness and acute geometry over appearance. The dramatically improved cutting performance is what I'd rather have.
All the above is to say: You might have to lift the handle more than just a little, and maybe a LOT, when getting into the belly and tip of the blade. The Sharpie method can help you see how much you need to lift the handle when grinding near the tip. Darken the edge bevel with a Sharpie pen. Then see where the ink comes off when you're grinding the bevel on the stone. Near the tip, you might notice the ink only coming off at or above the shoulder of the edge bevel, and not at the edge itself, because the edge angle there is probably much wider (more obtuse). For a visual training aid, I'd also suggest just holding different sections of the edge bevel flush and still against a flat & smooth surface like glass, and inspecting closely with a magnifier to see if the edge in that portion is making contact with the smooth surface. That'll open your eyes as to how much you might have to increase the held angle (by lifting the handle) against the stone when sharpening in different portions of the edge grind. Also keep in mind, because the held angle likely needs to be wider near the tip, the cutting performance of the fully apexed tip still won't compare to sharpness in the further aft portions, because the edge geometry is wider near the tip.
Alternatively, you could also just keep grinding at a consistent lower angle all the way to the tip. That will help you attain hair-shaving sharpness all the way out to the tip. Assuming the steel near the tip is thicker, it'll take much more time to apex the edge near the tip. Keep inspecting the edge under magnification as you go, to make sure you fully apex the edge near the tip. And the edge bevel approaching the tip will widen considerably as compared to the bevel width further back along the edge. For myself, I generally prefer edge thinness and acute geometry over appearance. The dramatically improved cutting performance is what I'd rather have.
Last edited: