Sharpening Serrated Question: The Tips!

[Bolster]

I don't have much experience sharpening serrated and could use some advice.

I'm having a problem: The concave portions of a serrated blade have sharpened fine, but the "tips" or "points" are still reflecting light off the edge, under examination. I dropped down in grit from the Sharpmaker brown stones, to a pair of triangular 600s I bought, and gave the edge a jolly good scrubbing with those coarser stones, and then back up to the browns, but those tips are still showing me they are blunt, with points of light reflecting off the points of the serrations.

If the concave portions are sharp, do you call it good enough? Are there secret techniques to get the tips sharp?

[Zipper]

I made a bit of a mess sharpening my first serrated Spyderco (H1 Salt 1).
This thread from @Vivi helped me a lot -

viewtopic.php?t=84544

[RustyIron]

Are there secret techniques to get the tips sharp?

Yes. There are secret grooves on the bottom side of the Sharpmaker.

Flip the Sharpmaker over and install one of your coarser stones. Freehand just the problematic area of the blade, making it more acute. If your goal is to use the 40 degree side of the Sharpmaker (20 degrees per side), you're going to shoot for about 18-19 degrees while freehanding. When you go back to using the Sharpmaker in the normal manner, you'll be able to hit the apex every time with no trouble.

You're only working with about 1/4" of the blade, so just about anyone can freehand it without drama.

[Wartstein]

Are there secret techniques to get the tips sharp?

Yes. There are secret grooves on the bottom side of the Sharpmaker.

Flip the Sharpmaker over and install one of your coarser stones. Freehand just the problematic area of the blade, making it more acute. If your goal is to use the 40 degree side of the Sharpmaker (20 degrees per side), you're going to shoot for about 18-19 degrees while freehanding. When you go back to using the Sharpmaker in the normal manner, you'll be able to hit the apex every time with no trouble.

You're only working with about 1/4" of the blade, so just about anyone can freehand it without drama.

Perhaps I get this wrong, but I assume you took Bolsters question about "getting the tips sharp" as if he meant the "tip" of the blade, so the plain edge section?
He is actually talking about the "tips" between the scallops though in the serrated part of the blade as I understand it.

[Evil D]

I reprofile the tips on my Edge Pro. It seems like the angle never matches the serrations, so I take the tip down to just below 15 degrees so I can sharpen it on either Sharpmaker setting.

*Edit*

I misunderstood, I thought you meant the plain edge blade tip. That's what I get for skim reading

The teeth themselves are probably just a higher angle than the scallops, so you basically need to thin them out/lower the angle until they match the rest of the scallops.

[dsvirsky]

In my experience (which may not mirror yours), when the tips of one or more serrations continues to reflect light after sharpening, it's because the tip has chipped:



I give it a little extra attention with the diamond triangles, check to see if it "catches" on my thumbnail (i.e., is sharp) and then don't worry about it.

[Bolster]

He is actually talking about the "tips" between the scallops though in the serrated part of the blade as I understand it.

Yes, exactly. Maybe I should have said "peaks" instead of "tips." Sorry about the bad terminology on my part.

If a serrated edge looks like: u^u^u^u^u , I'm talking about the ^ s. Having difficulty getting those sharp.

(But also, yes: The unserrated "point" of the blade is also giving me trouble, so the advice is appreciated there, too.)

[elena86]

He is actually talking about the "tips" between the scallops though in the serrated part of the blade as I understand it.

Yes, exactly. Maybe I should have said "peaks" instead of "tips." Sorry about the bad terminology on my part.

If a serrated edge looks like: u^u^u^u^u , I'm talking about the ^ s. Having difficulty getting those sharp.

(But also, yes: The unserrated "point" of the blade is also giving me trouble, so the advice is appreciated there, too.)

Your best bet is to sharpen every scallop separately. It’s a meticulous work but it pays. I advice you to watch Michael Christy’s youtube video on sharpening serrations.

[RustyIron]

Yes, exactly. Maybe I should have said "peaks" instead of "tips."

Ah, now I get it. Maybe I really should enroll in that remedial English course at the community college.

All I can offer is the standard advice that you've already considered: paint up the edge with a Sharpie, tilt the blade accordingly to match your desired angle, be patient or get some diamond stones.

For me, serrated edges don't need to be as perfect as my plain edges to make the knife cut nicely.

[USMC-88]

I found sharpening serrations the edge gets burrs just like plain edge knives. I started using the flesh side of a strop and the serrations popped to life after that.

[Wartstein]

...
For me, serrated edges don't need to be as perfect as my plain edges to make the knife cut nicely.

Same here... I kind of don´t notice in use when serrated edges have some not so sharp areas left, while with plain edges I certainly would..

[K1500]

Wouldn’t the peaks be at a lower angle than the scallops, since the are longer?

[yablanowitz]

The points of the teeth suffer the most wear and damage in use. To get them sharp again, you have to grind away the scallops as much as the points have worn, or change the angle. Getting back to factory sharpness using only the brown rods is going to take some time. If the points are very worn, a lot of time. CBN or diamond rods will reduce the amount of time it takes by removing material faster.

[Evil D]

Wouldn’t the peaks be at a lower angle than the scallops, since the are longer?

No they'll be the same angle, but the steel itself in those areas (the tips of the teeth) will be thinner. Same angle, but lower on the blade grind means thinner steel since the blade grind is a V. Serrations are ground at the same angle and the same direction throughout the blade, with the only exception likely being human error due to not holding them perfectly square to the stone (or by robot or however they're doing the grinding).

To dumb it way down, serrations are basically just a wavy chisel grind.