Question on blade thickness.

[The Deacon]

Been thinking about this on and off for quite a while, but a few threads lately have made me even more curious. I've carried and used a pocket knife for about fifty five years. Prior to "discovering" Spyderco five years ago, I don't think any of them ever had a blade more than 2mm thick. Most were probably a good bit thinner than that.

In all those years, I cannot recall ever breaking or bending a blade. Buggered up the very tip of a couple using them as "emergency screwdrivers", may have snapped the very tip off a couple more doing equally dumb things, but never broke or bent the blade itself.

Same thing in the kitchen, except even the Spyderco kitchen knives I own are less than half the thickness of my Stretch. Most of them are longer than any folder, some twice or more as long. Can't recall ever breaking one, even "back in the day" when the only quick way to defrost a freezer was to hack the ice out.

Truth is, I cannot imagine anything I would ever consider using a folding knife for that the 4mm thick blade of the Military would do any better than the less than 2mm thick blade of my 8" Spyderco chef's knife. On the other hand I know from experience that, all other things being equal, a thinner blade will out slice a thicker one. As much as I like the Stretch, I know I'd like it even better if the blade was half as thick.

So my question is, why are the blades on Spyderco - and many other brands of folders today - so thick?

[huugh]

My guess is it originated from the "tactical" styled knives, when the demand for "indestructible" (i.e. overbuilt) folders arose.

But I'd like to hear the "official" reasoning too.

[zenheretic]

"The market demanded it" is my guess...

[Piet.S]

Could be worse.
Sometimes I see people proudly showing off their new fixed blade with a 8 mm thick spine.

[Franco G]

Deacon, you are right. Actually, your chef's knife should be thicker - most chef's knives, i. e. ones from Wusthof, Vinzer, French knives are quite heavy. Japanese knives are heavy too.

One reason for thick Spayderco blades is a hole. It needs very wide blade near the tang in order to have enough place for a hole.

It is also strange to have a fixed knife with a thick blade, and very short tang, for example an old Temperance. As you may see from the photo below, Temperance has a half sticky tang. Not enough for serious outdoors.
Sal's argument against, saying that nobody complained about break is tricky. Many fans on forums use Temperance in kitchen! No break, of course.

Disclaimer: I do not claim a Temperance were not strong. I claim it would be much sturdier and stronger with a full tang (skeletonized or sticky).
Am I right? I think so, Sal announced a new Temperance with a full tang.

Franco

P. S. A tang near the blade should not have square angles. It should be radiused (oval)! This is not a point for discussion, this is physics.

[El Tigre]

A 4mm lock back is a lot strongest than a 2mm lockback. A thinner blade cuts better. A thicker blade locks better.
My favourite blade thickness is 3mm. :cool:

Greetings

"El Tigre"

[J.B]

I guess, it has to do with feelings and fears. A thicker (bladed) knife rather feels unbreakable. Even though most pocket knives are often only used in non emergency situations, users may subliminally think it could come to an emergency. Then one of the last things that should happen is a broken blade.

Outside I tend to have at least 2 EDC knives with me, one sheeple friendly model that cuts nicely and can do most jobs if not all and one stronger (perhaps non stainless or thicker fixed) bladed backup knife.

JB

[The Deacon]

"The market demanded it" is my guess...

My guess is it originated from the "tactical" styled knives, when the demand for "indestructible" (i.e. overbuilt) folders arose.

But I'd like to hear the "official" reasoning too.

Am sure both those things are connected, and are one factor but I suspect there's more involved as well. Cost may well be a factor. Many older folders had tangs thicker than their blades. Some that use steels that can be stamped out still do. It would cost more to thin the blade out than to leave it the same thickness as the tang.

A 4mm lock back is a lot strongest than a 2mm lockback. A thinner blade cuts better. A thicker blade locks better.
My favourite blade thickness is 3mm. :cool:

Greetings

"El Tigre"

Not really. A 4mm tang may create a stronger lock and "lock better", but what's forward of the tang has no impact on lock up. There's no necessity for the blade itself to be as thick as its tang.

[Shike]

Deacon:
It could also have something to do with differences in materials. Most of the latest knife fads evolve around newer steels. Another trend (not that new) is for heat treating and tempering to a higher Rockwell. This requires thicker blades to compensate for brittleness. Older factory blades were thinner because most of them were hot drop forged (Puma, Hen and Rooster, etc). To counter this you might like to look at blades that are forged as they tend to be thinner. Even forged fixed blades are thinner, than those made by stock removal. Even if the spine is 1/4 " it will (should) have the proper blade geometry.

One reason for thick Spayderco blades is a hole. It needs very wide blade near the tang in order to have enough place for a hole.

Franco

I think Deacon was talking about thickness and if I understand correctly you are talking about width.

Best regards

Shike

[Fred Sanford]

The older I get the more I like thinner blades. Right now I'm loving the Centofante Spydies and the blades on my good old Victorinox SAK's.

I can see why traditionals are so popular.

I also agree with you Paul, I've not broken a blade before. I've broken tips but most of the time it's because I was not using the knife to cut things. :) ....or because I dropped it.

I do like the thick blade on my Para but I think that is just the little sense of security it adds, however false that sense may be.

[Franco G]

I think Deacon was talking about thickness and if I understand correctly you are talking about width.

Best regards

Shike

What I mean is the following: you need a large width because of a hole - then, with flat grind the blade thickness grows when you go from edge to the spine. Hope this is more clear. Quite simply, if the blade (width) of Manix stops in the middle it would have maybe 3mm instead of 4mm at the spine.

Franco

[J Smith]

Much could be due to thickness of the scales.The Military would not feel right with thinner scales plus the grind on the Milli most likely needs the thicker blade.The way it is ground you get to the 2mm thickness about half way down the blade.I have snapped blades on Case slip joints and box cutters by cutting thick cardboard.I know what caused it,when you run the blade down a long cut in the cardboard the cut starts to get off thus bending the blade without you noticing if it continues it will snap a thin blade.

[Cptdesoya]

I was sad to see even the Mili changed in blade thickness. I have my chefs knives for cooking and my carry blades for as need be.

I like my santo, chefs, bread knives to be solid but slim.

Ive always counted on my folders to be stout, tough, ready for anything.

My new Mili is obviously slimmer than my old 440v knife.

Why is that?

[J Smith]

The blade in the Military should be the same.The newer models have slight thinner scales.

[yablanowitz]

Cptdesoya, you have good eyes. The blades on my old 440V and ATS-34 Militaries measure 0.010" thicker than the blades on my newer Millies. I thought it was an optical illusion due the the G-10 scales being 0.011" thinner (each) than the scales on the newer models. Live and learn.

Personally, I do remember breaking a few pocket knife blades. Not all of them were thin, and not all of the breaks were due to prying, either. It does happen less often if you remember that different tools are made for different jobs, and most really aren't interchangeable.

I find the blades of most modern design knives to be annoyingly thick, but then I find locks unnecessary and one-hand opening a nice but non-vital feature as well. I guess that puts me solidly into the "old fart" category.

One-hand opening seems to equate to "tactical" in many people's minds, and "tactical" equates to "weapon" and "weapon" equates to "thick/heavy". It also seems to awaken "Mall Ninja Syndrome", which requires the knife to double as a climbing piton/body armor and car door defeater (thanks for that one, Lynn). The sad truth is, Sal had to reinforce the tips on the Delica and Endura because he got so many back with the tips snapped off, when the old tips were thicker than I like. With that being the case, I expect any call for thinner blades on Spyderco knives to fall on deaf ears. Spyderco has earned a reputation for high quality knives. It isn't Sal's fault that people confuse "high quality" with "indestructible". It just means he has to allow for the "idiot factor" in order to keep that reputation.

I'd love to have something like my Schrade 8OT stockman with S90V blades, but I don't expect to see it unless I win the lottery and commission a custom.

[cornelis]

My edc for the last half year is a one hand opening, lock back Laguiole with a nice olive wood handle. It's from Fontenille Pataud.The thin blade cuts like a razor. Love this French beauty!

[cobrajoe]

I would love to see a small blade, like a dragonfly or lava or a mini JD (that would be my favorite :D ) with a thin flat ground blade. It would be an amazing slicer, but it would be small enough for most people to realize that you're not supposed to open a can of beans with it.

[dogrunner]

Personally I like thinner blades (to a point) because I use knives to cut things, not chop wood or pry. Especially for folders this is sort of a no-brainer. Having said that, I have broken tips on thinner blades and even permanently bent a blade on a thin kitchen knife (not a spydie), because the knives were what I had on me when I needed to apply some lateral force. If your only use is in the kitchen, this will rarely be an issue, but when you need some dry firewood fast in cold weather, sometimes splitting a wet piece (or doing whatever harder use chore) puts more pressure on the blade than just slicing and dicing would. A thicker blade (to a point) surely is stronger (all else equal). I still don't like thick blades that don't cut worth cra& though. It's a knife, it better be good at cuttin' stuff :)

[Dr. Snubnose]

Slicing ability depends upon two primary characteristics. First is edge geometry. The more acute the edge angle, the easier it will slice through material. Blade thickness will have an effect as well; the thicker the blade, generally the less acute the edge angle will be, all other things being equal. This varies to a degree by how the blade is ground, so the thickness isn't as important, but can have a detrimental effect if it is too thick. The blade also needs depth, as well, for added strength. A blade with skinny proportions is inherently weaker than one which is deeper. The back or spine should be full for added strength, not sharpened with a false edge or narrowed down, though rounding the top is fine. If the grind doesn't go all the way to the top, that adds strength as well. Thicker knives are harder to use for fine detailed work...so If you insist your knives be plenty thick I suggest you carry a thinner blade in a folder or fixed blade design for those purposes....If I'm in the wilderness I certainly want a thick blade for chopping, hammering and survival like tasks...but If I'm in the kitchen or doing general daily knife tasks (not like opening paint cans) then a thinner blade will do the trick for me....Doc :D

[dogrunner]

Exactly. When I head out for camping / backpacking / backcountry whatever I take a mid-length folder to be sure something is always in my pocket (Delica or Paramil or maybe Endura) and a mid-length fixed blade in my always-with-me daypack (Falkniven F1 or Swamprat Howling Rat) - there are lots of great choices for both. If I am planning on being out I always also bring a small axe (Granfors Bruks Wildlife hatchet). I still don't take a knife for chopping :cool: although lots of folks might have different strategies. The knives have to be good cutters, whatever else they get used for. The fixed blades give me something for harder use, the folders give me something that never get used for anything but cutting stuff (knife jobs, not axe jobs). Hence, thinner is generally better, as long as it is not too thin. I guess the real question, then, is what is thin and what is thick ? Seems to me that 3 mm works pretty well on my Endura and the 4mm on my Paramil or Lil Temp (broad flatgrind) work just fine too !! :) All my :spyder: :spyder: are good cutters.