Why does the strop feel "sticky" with some knives? Also, pre-treatment?

[stitchawl]

Et tu Stitch?

Don't make me take a pic of the entire hide with its irregularities, holes and discolorations.

No...no! You're safe at the Forum this coming March 15th! Just joking! Obviously we can't really have any knowledge of what the stuff is from just a photo. All we can tell is that it's thin and it's shiny. Besides, with the Naugas still being on the Endangered List, and not being indigenous to West Coast ecosystems anyway, we know you wouldn't be using it.

Stitchawl

 

[Omega Leather Works]

No...no! You're safe at the Forum this coming March 15th! Just joking! Obviously we can't really have any knowledge of what the stuff is from just a photo. All we can tell is that it's thin and it's shiny. Besides, with the Naugas still being on the Endangered List, and not being indigenous to West Coast ecosystems anyway, we know you wouldn't be using it.

Stitchawl

Oh dear... This whole post made me cackle.

Thanks for that, it's been a terrible day.

 

[Omega Leather Works]

Rather than start a new thread I'm just going to report a new finding here...

And that is, once you get a bevel down to the teens (inclusive) the whole shebang gets wacky!

I took my No. 8 as far as I can realistically go in terms of edge accuteness. I can only guess as to what the angle is. I know that each side is well below 10.

I ended up taking a few really random pics.

The "project" has been an ongoing process for a while now, as I'm trying to pass a successful HHT.

After much blade work I got tired of the ugly look to the thing and polished it pretty nicely. After this latest round of thinning, not only the edge, but the whole blade, it was looking pretty ugly again.

Thank goodness Opinel puts their mark deep into the blade!

Dry (manual) grinding the blade on w/d SiC 220 grit...

Then a quick progression through 400 wet.

I actually liked the look at that point, but I knew that would pass. I continued to 800 wet.

Then got distracted and stopped taking pics.

Doesn't matter, it wasn't about the pics, OR the finish, or even for posting on the forums for that matter. Nope, I've still got my eyes on the prize.

In case you're wondering, I'm no closer now than I was yesterday to a passing test. I have a lot of refining to do, but I thought one thing was really interesting at this thin of an edge... I noticed that when I use a light stropping (edge trailing) draw on medium grit paper (3M 1k SiC), that I can easily see a burr appear almost immediately. That is, within an inch or two of pulling back on the blade.

I've got some thinking to do on this. On one hand, I don't want to remove too much metal, but on the other I'm concerned about the frailty of the edge. I don't mean that I plan on edc'ing the knife, but I'd like it to resist folding by pressing on it with my finger tip. Also, I'm beginning to think that I need to store it open. I can't tell, but I'm guessing that the edge contacts the interior.

Any thoughts on any of this?

I'm still not sure that this is the right blade (steel?) for this, but it's the best I've found that can readily be called a "knife".

It's getting very close to being a zero grind, but at this point it's convex, and I think I need to keep it as such, or risk material loss by accident, like when I'm trying to polish the blade. As it stands it's nearly flat when using my thin leather strop.

Comments and suggestions are welcome. I'm pretty much flying blind here. I've already invested more in sharpening stuff than many of these knives cost together, then there's the time involved. Of course that's the fun.

 

[BluntCut MetalWorks]

Your Opi bevel looks like between 14-18 degrees inclusive. I grinded my #9 bevel all the way to the stamp 'carbone', which has angle around 8* inclusive. After a series of tests, the bevel now is around a convex 15* inclusive.

I didn't like this knife until I removed ~0.8mm away from the edge (i.e. the blade height is now 0.8mm shorter than factory). The factory edge & 0.5mm edge metal were sucky at best. I suspect the factory edge got detempered by machine grind.

 

[Omega Leather Works]

Your Opi bevel looks like between 14-18 degrees inclusive. I grinded my #9 bevel all the way to the stamp 'carbone', which has angle around 8* inclusive. After a series of tests, the bevel now is around a convex 15* inclusive.

I didn't like this knife until I removed ~0.8mm away from the edge (i.e. the blade height is now 0.8mm shorter than factory). The factory edge & 0.5mm edge metal were sucky at best. I suspect the factory edge got detempered by machine grind.

Thank you very much for your input!

Like I said, I'd have to guess at the bevel, but the initial edge (for today) was done with a mix of freehand, and the lowest setting on the edge pro (clone, should be comperable) so I'm sure it's in the mid to upper teens, just like you guessed. I thought about trying a riser, but didn't. It's easy enough to push the edge off the deck a bit...

Interesting comment about the poor factory edge steel. So far I've had nothing but good luck on this one. I do see that as a concern pretty often. I had some mystery chips in the m4 edge on my Contego. Not even sure how they happened. I've since put a new, more acute, edge on her so I'm hoping that that won't happen again. It sure cuts nicely!

My question for you, though, is why did you grind such an acute edge on your Opinel? Were you just playing around, or did you have any goals? Did you learn anything from doing it besides what you've already mentioned?

I'm also finding that stropping is much more finicky now. I can't seem to go from kind of sharp to really sharp (highly technical terms,I know!) like I did before. But one single (very light) pass on a translucent ark stone seems to separate the edge from sharp-ish (I wish there were more quantifiable terms for each level of sharp, but here I'm referring to an edge that will shave with ease) to very sharp (shave with great ease), then followed by stropping takes it to a higher level still.

That's kind of confusing. I'm just saying...

Kind of sharp + strop = kind of sharp
Sharp + strop = very sharp

I'm seeing more net gain, on the strop, when I start out sharper...

Jeez, does that make any sense?

 

[BluntCut MetalWorks]

My question for you, though, is why did you grind such an acute edge on your Opinel? Were you just playing around, or did you have any goals? Did you learn anything from doing it besides what you've already mentioned?

I'm also finding that stropping is much more finicky now. I can't seem to go from kind of sharp to really sharp (highly technical terms,I know!) like I did before. But one single (very light) pass on a translucent ark stone seems to separate the edge from sharp-ish (I wish there were more quantifiable terms for each level of sharp, but here I'm referring to an edge that will shave with ease) to very sharp (shave with great ease), then followed by stropping takes it to a higher level still.

That's kind of confusing. I'm just saying...

Kind of sharp + strop = kind of sharp
Sharp + strop = very sharp

I'm seeing more net gain, on the strop, when I start out sharper...

Jeez, does that make any sense?

I learned very acute edge is very difficult to sharpen, especially removing burr & wire-edge. After sharpened v2 at 7*, m4 at 10-12 (I don't remember) and bunch of other knives, I end up using mainly edge-lead stroke for grit beyond 2K and or last finishing stone whichever lower. And I don't strop for ultimate sharpness but actually edge-lead into 0.1um polydiamond paper stone (printer photo paper coated with polydia suspension). The edge just too thin too support edge-trailing (strop). Just think, it takes certain amt of pressure for the abrasive to dig-in and fracture/abrade the steel away. Well, when the steel is actually carbide grain, then more pressure is needed, which surely beyond the steel tensile strengh at sub-micron thickness.

 

[Omega Leather Works]

Okay, thanks again.

So far I'm not struggling with the wire, but I sure wouldn't be surprised if it starts to give me trouble soon. Right now I'm just lightly (blade weight) slicing into an edge of wood, which is removing it.

Edge leading beyond 2k. I'll remember that.

 

[Obsessed with Edges]

For what it's worth, the steel on the 'carbone' Opinels seems to be pretty soft(ish). I've noticed, after thinning the edge somewhat on mine, it's noticeably vulnerable to impacts/dings into the edge.

I haven't had many (if any) issues with wires/burrs in sharpening mine (all edge-trailing). Pressure exerted plays a HUGE role in that (far more than anything else), so focusing on keeping it light is key; more so as the edge gets thinner. With edge-trailing sharpening on the Opinel, I've been laying the lower half of the convexed blade flush to my sandpaper/strops, and using that wide 'base' to help stabilize and regulate pressure at the very edge. Much easier to do this on the Opi blades, thanks to their blade grind. I've been touching up and maintaining all of my blades with edge-trailing lately, and I'm convinced it's just one of those things that can produce good results as one becomes more accustomed to it, and comfortable with it. Light pressure, light pressure, light pressure (etc.) is what makes the difference.

That's my $0.02 worth...


David

 

[Omega Leather Works]

I may have to build a double thick strop, find one of those artifacts called a "mouse pad" ( ), or use another, thicker piece of leather for that.

It may prove worthwhile in order to keep the edge stable though.

Good thinking!

 

[Obsessed with Edges]

I may have to build a double thick strop, find one of those artifacts called a "mouse pad" ( ), or use another, thicker piece of leather for that.

It may prove worthwhile in order to keep the edge stable though.

Good thinking!

Based on the habits I originally formed when using a ceramic pocket hone in-hand, I've figured out that regulating pressure is easier if the hone (strop) is held almost vertical, or angled slightly off of vertical, and directing the sharpening/stropping stroke along that more vertical plane. Not so much weight (literally by gravity) is directly down into the hone/strop this way, as it would be if the hone were laying flat (horizontal) on a table or bench. For me, it is always more difficult to minimize or regulate pressure when standing over and leaning into the hone when it's laying on the table, and the edge is always going to take the brunt of it.

I still prefer to go thinner and firmer for my stropping surfaces, so there's much less opportunity to round over the apex. Use the vertical or near-vertical angling of the hone/strop to regulate and/or minimize the pressure on the edge. Alternatively, you could also place the hone/strop on the table or bench as usual, but operate from a position that's lower, relative to the table, so your stroke is away & back in a plane that's nearly at eye-level, or slightly below eye-level. The whole idea is to minimize how much of your own weight and pressure is above the plane of the hone/strop. This may all sound a bit odd as compared to the 'proper' bench technique demonstrated by so many 'expert' sharpeners, but I've come to realize how much it's worked for me, in approaching it this way.


David