Let's Talk About Sharpening Our Survive! Knives

Silver Needle said:
This is my favorite new thread!

1. Where does Ceramic fit in with stones and strops? In between? Is this more of a finishing step?


2. Who really pays attention to edge angles? Some people seem really happy free handing in the field, but then I hear other guys talking about the differences and benefits between 17 and 20 degrees per side!
Click to expand...


1. Ceramics are a finishing step. They're very fine. I never go over 1200 grit ever on stones and recommend that most knives are 600 grit before they hit the strops. Sandpaper and belts are different.


2. I use pretty thin edge angles because it usually increasing the cutting ability of most blades. 3V handles thin edges well, even batoning wood with my GSO 6 isn't an issue and I could easily gut and skin a deer with it and then shave my arm. If it's a wood processor or a heavy abuse knife I won't sharpen it to a very thin edge, but if you tell me you're skinning with it then yea.
 
Silver Needle said:
1. Where does Ceramic fit in with stones and strops? In between? Is this more of a finishing step?
Click to expand...

MoS is correct, they should be used as a finishing step. They're not great at removing material, but instead excel at refinement. An 800 grit diamond hone and an 800 grit ceramic rod won't necessarily operate in identical fashion.
 
Thanks, guys!

As far as the question on sharpening 3v, I've never had any problems at all. I can get my 3.5 hair shaving on my little diamond plates pretty quickly. If I can track how much I've sharpened by counting strokes instead of counting the minutes then I feel pretty good. After a morning of box cutting I could shave arm hair after about 40 passes on each side.
 
DMT 8 Inch DuoSharp® Bench Stone - fine/coarse.
DMT Diafold® Double Sided Sharpener - fine/coarse.
DMT Diafold® Serrated Knife Sharpener - fine/coarse.

I also have a Work Sharp Guided Field Sharpener which surprisingly does an effective job, especially in the field carried in a pack.
The DMT system's are my favorites.

DSCN1665_zpsb51ea59f.jpg


7guidedfieldsharpener_zps187150b5.jpg
 
Stropped my 3.5 and then dropped it edge-down on the tile floor while trying to put it back in the sheath. Flattened a big section of the edge. Ouch.

5 minutes with the Norton stone and a paint stick strop and I'm back to shaving hair which means it'll be good enough to feather some sticks for a fire.

At least I didn't try catching this one on the way down.
 
I stuck my 5.1 in the dirt this morning *spanks hand* only to pull it out and see I hit a rock on the tip and rolled a small section. I'll be working on that tonight!
 
Ask me if the GSO-5.1 or 4.1 hit a rock during all that throwing.
Heck, ask me if the 4.1 knicked the steel bolts holding the target in place.
Ask me if there were any rocks in the soil around the sapling i dug out.
These are tools to be (ab)used, and Guy's dedication and warranty leave me without a worry. :cool:

That GSO-4.1 came to me ~20-dps and 0.020" behind the edge.
Cutting that glued/wooded carpet, it lost it's edge. Cutting through the lip of the can, it rolled and flattened due to the wobbly nature of how I was applying the force. Digging in the sand/dirt and throwing... well, i hadn't sharpened the edge after cutting through the can, so it's hard to say if those actions caused any extra damage. Can you see the edge-damage in the pic below?

P1030870.jpg



Here is the photo posted by ni1s of the damage on his 4.1:

IMG_1509.jpg



It's shallow - maybe .005" or ~125 microns. We're talking about grinding on a metal face only ~0.030" wide. Removing that amount of metal with a strop and green compound (which is only ~0.5 micron grit) would take a LONG time, but using a DMT Aligner with the black (220-grit / 60 micron) or even blue (325 grit / 45 micron) hones, the strokes are few and fast. Once the damaged metal is gone and the apex reshaped, stepping up to 600-grit (red) and maybe 1200 grit (green) finishes the job leaving a nice, toothy edge that looks like nothing ever happened.



EDIT to add: About the "sharpie trick" - not only does this help you maintain an edge at the factory angle, you can use it as a guide to change the angle :) I use a red-sharpie since my eye picks that up more easily. If the factory edge isn't cutting as well as I'd like, I'll paint the bevel with the sharpie and then adjust my sharpening angle such that I'm removing the edge-shoulder. Once you have a good start on bringing down the shoulder, you can paint this "back-bevel" blue or some other color to help you maintain that angle, and then just continue to grind until the red paint is gone all the way to the apex. Then flip the blade over and repeat the process on the other side.

Regarding angles, it's important to realize that knife cutting performance isn't so closely related to angle as it is to thickness. Angle is simply a means of describing thickness - the space between the bevels.

My Gerber Strongarm (nice knife) came with a well-finished edge at 15-dps (30 inclusive), the GSO-4.1 was 20-dps (40 inclusive). Which do you think is the better cutter? The trouble is, you don't have enough information.
That Gerber is ~0.035" behind it's edge with a primary bevel near 10-dps, while the GSO is only ~0.020 behind the edge and <5-dps primary.
Because of the edge-angle, that GSO is only thicker for ~1mm of cutting depth beyond the apex, lending it increased durability (stiffness) against all the forces it must encounter while suffering very little increase in force required to initiate a cut to that depth, and after it breaches that measly 0.020" thickness, it slides on through :cool:
The Gerber at 30-inclusive is a little less durable at the apex than the GSO, it'll sooner need a microbevel added (depending on use) but it can make that initial bite to 1mm more easily... the trouble is, most of my cutting is more than 1mm deep, and the Gerber maintains that edge-angle for ~2mm and requires a breach about 2X wider than the GSO to continue the cut, and the angle after the edge-shoulder is ~2x greater than the GSO primary - the Gerber is a fatter wedge despite the thinner angle near the apex. This makes the Gerber strong as it's name suggests... but reduces its cutting performance significantly.

What i am trying to get at is, don't worry about trying to tailor your angle to exactly 15-dps or 20-dps in a knife that is 0.020" thick like a smaller GSO. Focus instead on getting the knife as sharp as you need it to be. If it meets your performance needs without suffering durability issues, go ahead and try lowering your sharpening angle slightly (by eye, using the sharpie-trick) to thin the edge-shoulder and add a back-bevel, maybe leave the apex alone, and see if that improves cutting performance without reducing durability in your use. If durability suffers, keep a stout microbevel in place to support the edge.

To add another comparison, i have a couple of knives that are ~0.005" thick behind the edge - it doesn't matter if their edge is sharpened to 20-dps or 40-dps, those knives cut with aggression because they are so thin, they make the GSO look like a brick... but those thin edges flex and are likely to snap away entirely if I were to treat them the same as my Survive! knives :eek: Thickness is what determines edge-strength, thickness is what determines cutting efficiency.

And now I'm off-topic, sorry about that. :(
 
Last edited:
After beating up the edge its time to clean her up and sharpen her back to a fine edge.



The rolls came right out and it didn't take too long on the sharp maker. 20 strokes on the med grit stones and about 30-40 on the fine. I think she cleaned up nice.



Inspected by the good eye of Jinx....



And Jinx approved!

 
I resharpen on belt sander, hand strop in between. usually.

If I want a flat V edge, I do it by hand with diamond and ceramic stones.

I have an edge pro with extra water stones, but it is so tedious to set up... I can do as well on my belt sander.
 
i have been following this thread with a lot of interest that said, as i have admitted before...my dark dark secret is my lack of sharpening skills. I use a sharpmaker for most of my knives and it does ok, but havent been willing to try on my survive knives or other more pricey knives. One of these days i'll figure it out....
 
redwood22 said:
i have been following this thread with a lot of interest that said, as i have admitted before...my dark dark secret is my lack of sharpening skills. I use a sharpmaker for most of my knives and it does ok, but havent been willing to try on my survive knives or other more pricey knives. One of these days i'll figure it out....
Click to expand...

Don't worry, your secret is safe here on the internet... :p


Really though, I'm right there with you. This thread reminded me if something I want to try when I get a bench stone. The below is hijacked from a subforum far, far away...







MoS, would that binder clip mess up or hurt a DMT bench stone or duosharp?
 
I can do the whole mousepad/sandpaper thing... but I don't like it. Too soft. I prefer a piece of cardboard. I can do the edgepro. I can do freehand with diamond/ceramic or old school hard stones. I can do belt sander.

I have not, however, done the japanese waterstone thing yet. Well, I have some for my edgepro but that doesn't count.

Maybe I should tackle learning that next.
 
Silver Needle said:
Don't worry, your secret is safe here on the internet... :p


Really though, I'm right there with you. This thread reminded me if something I want to try when I get a bench stone. The below is hijacked from a subforum far, far away...







MoS, would that binder clip mess up or hurt a DMT bench stone or duosharp?
Click to expand...

I don't think so. But a diamond stone will grind away that clip at an alarming rate and I can't almost guarantee that thing will scratch your knife up if you slip at all with it.
 
You must log in or register to reply here.
Back
Top