Grind Question

[Blackhair]

Hi, I have a question about knife grinds, specifically in relation to PE blades.

I know enough about the various blade grinds, and what they're better for, and all that technical info, what I don't know is the sort of info that only come from seeing different blade grinds in action over the years (the sort of info that never seems to show up on google searches :p ). And before you ask, yes, I tried doing a forum search, but I didn't find anything. That doesn't mean that I read every post of every thread that came up, so if someone finds something in forum search, don't be too hard on me. Please? :o

So, the questions:

- How much better do Flat and Hollow-Grind cut over Saber-Grind?
- How much better does Saber-Grind hold up to abuse as opposed the Flat and Hollow-Ground?
- Does Saber-Ground still take a good edge?
- Are any of the grinds I mentioned significantly harder or easier to sharpen?
-Does blade grind make any real difference in how well an edge holds up over use? Or is that mainly determinate on the type of steel used?

Yeah, basically I'm trying to decide between Saber, Flat, and Hollow-Ground. (I won't say why, though. I don't want to start a "This folder is the best, because..." thread)

Oh, and also, I mainly use my knife for pretty light-duty work. I'll sometimes have to cut boxes, but the most heavy-duty work that my knife has been used for in the past year or so was cutting through some industrial-strength rubber tubing with fiber-reinforcement on an old propane stove. If that helps at all...

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Gah, alright, simplifying things up here...

Which would you rather have, a Waved, Saber-Ground, FRN Delica; or a Hollow-Ground, SS Delica?

[smcfalls13]

- How much better do Flat and Hollow-Grind cut over Saber-Grind?

Well first of all, you can have a Saber Flat grind, and a Saber Hollow grind. A Saber grind just doesn't cover the whole width of the blade, the grind starts somewhere in the middle.

As a result, on Saber ground knives, the thickness of the edge itself usually tends to be higher than on Full Flat or High Hollow ground knives.

The grind is only important in regards to what material is being cut(see below), the edge thickness determines how easily it will cut( .001" edge is going to cut better than a .01" edge, for obvious reasons)

- How much better does Saber-Grind hold up to abuse as opposed the Flat and Hollow-Ground?

To be perfectly honest, I notice no difference. They all chip if they hit concrete, and they all get dull around the same speed. On folders, I don't think the difference is as noticeable as it is on larger fixed blades.

- Does Saber-Ground still take a good edge?

Go grab a D4 and you can answer that question yourself ]- Are any of the grinds I mentioned significantly harder or easier to sharpen?[/QUOTE]

Most people find Chisel grinds easy to sharpen, because you only have to sharpen one side, and than remove the burr. I'm a moron and can't do it however, so take that with a grain of salt.

Convex edges CAN be extremely easy to sharpen as well, with just sandpaper and mousepad, but again, I'm a moron.

-Does blade grind make any real difference in how well an edge holds up over use?

In some cases, yes. I find a full flat ground blade is best for food prep(dicing veggies, fruit, cutting a sandwich, etc). Though Doc Snubnose's Meat tests show a Hollow ground blade slices meat better(see his Chinook II vs. Chinook III test).

Convex edges are best for chopping blades, because the shape of the blade actually wedges the material apart.

Chisel grinds are best for SD blades, because they are often so thin, and so sharp, they won't hold up well against normal use.

These are all my own personal opinions though, and are by no means gospel.

Or is that mainly determinate on the type of steel used?

The steel is secondary. If the edge geometry is appropriate for the steel, and exploits that steels particular strengths(see Joe Talmadge's Steel FAQ) than just about any steel can be good.

Yeah, basically I'm trying to decide between Saber, Flat, and Hollow-Ground. (I won't say why, though. I don't want to start a "This folder is the best, because..." thread)

Full flat grind is the preferred grind around here, it seems. Though a nice high hollow grind is nicer looking, and cuts just as well.

Oh, and also, I mainly use my knife for pretty light-duty work. I'll sometimes have to cut boxes, but the most heavy-duty work that my knife has been used for in the past year or so was cutting through some industrial-strength rubber tubing with fiber-reinforcement on an old propane stove. If that helps at all...

For that kind of general utility, any blade grind will suffice, but I find hollow ground blades cut carboard with less scratching on the blade. Completely aesthetic, I know, but it bears mentioning.

Which would you rather have, a Waved, Saber-Ground, FRN Delica]

They're both great for what you have in mind, so the deciding factor for me would be price. FRN is cheaper, so waved Delica it is. :p

[Blackhair]

Thanks for your in-depth answer, smcfalls :)

I think I have all the info I need now. Now I just have to go to a store that carries Spyderco's and get my hands on a few to see how they feel to me.

So, no more postings please, people :D

[steeltiger]

For my use hollow ground blades cut stuff like twine, butt full flat grinds cut stuff like veggies and cardboard better, because of being (over average thickness across blade) slihgtly thinner.
So for me, hollow if I need to cut something, flat if you want to cut through something, but the differange is very small. just my $.o2

[The Deacon]

The other thing to keep in mind is that legitimate comparison of the various grinds can only be done using blades that are identical execpt for the grind. Thickness and width are also factors, so varying them impacts the results. As an example there would (theoretically) be no difference between the "cutting power" of a 1" wide 4mm blade with a full flat grind, that of a 2" wide 4mm blade with a 1" high flat saber grind, and that of a 1/2" wide 2mm blade with a full flat grind. And yes, I am aware there is a flaw in the third example, since it does not account for the primary grind, so the actual width of the 2mm blade which would cut indentically to the two 4mm ones would not be exactly 1/2", but the point should be clear.

[d.g.g]

http://forums.egullet.com/index.php?showtopic=26036

There is no best grind and even the same grind varies as far as sharpening ease and cutting ability depending on the shape and thickness and tempering of the blade and the type of steel it is made from.

[The Deacon]

The only thing I can say with absolute certainty is that the Schempp Persian I had reground by Tom Krein into a full flat grind performs noticeably better than the standard hollow saber grind when cutting thick firm material like a raw potato and slightly better when cutting thick soft material like a tomato.

[tonydahose]

in my opinion i can get a full flat grind sharper than the others. just my experience and i might not be the best at sharpening.

[Slick]

Full flat is my favorite. Easiest to sharpen on an Edge Pro and easiest for me to polish up if I'm feeling shiney.

Also like the spear point and the hollow grind and all the other grinds.