Do Smaller Knives Need As Much Edge Retention?

[Ten_Mile_Knives]

I was thinking, if a blade made of some steel is only 3-4" long wouldn't the cutting forces near the tip be much less than a blade 10" long. If they are then wouldn't a longer knife dull more quickly do to edge damage? Basically can shorter knives get away with lower quality steel more than long knives?

Does size matter?

 

[danbot]

As far as edge retention goes, size does not matter. (Comparing apples to apples for the cutting task of course).

 

[Ten_Mile_Knives]

Maybe a better question is weather the tip of a long knife dulls more quickly than the base given the same tasks? Like if I twist a little while cutting then wouldn't the tip be more likely to roll over than that base because it's further from my hand?

 

[Lapedog]

Maybe a better question is weather the tip of a long knife dulls more quickly than the base given the same tasks? Like if I twist a little while cutting then wouldn't the tip be more likely to roll over than that base because it's further from my hand?

Or won’t more force be applied to the tip at the end of a chop using the tip during a tip chop due to the longer lever?

I think that toughness would be very important here to prevent the edge from rolling. So it would need more edge retention in terms of edge stability if not abrasion resistance. In theory at least.

 

[danbot]

I suppose with the longer knife, it's length will increase the leverage or torque that you could exert on the tip, but a good heat treat should allow for flexibility without rolling during a reasonable cutting task IMO.

 

[cashville]

I guess on the flip side of things, one could argue that a shorter knife needs better edge retention. For instance, with a shorter blade, you may be doing more push cuts than slicing (an example would be breaking down cardboard). I don't have much fun with a Spyderco Native that has gone dull due to the relatively short cutting edge.

 

[marcinek]

I suppose with the longer knife, it's length will increase the leverage or torque that you could exert on the tip, but a good heat treat should allow for flexibility without rolling during a reasonable cutting task IMO.

Leverage possibly, torque not really, unless the longer knife's bigger-diameter handle might increase the torque.

 

[marcinek]

I guess on the flip side of things, one could argue that a shorter knife needs better edge retention. For instance, with a shorter blade, you may be doing more push cuts than slicing (an example would be breaking down cardboard). I don't have much fun with a Spyderco Native that has gone dull due to the relatively short cutting edge.

Yep. Most likely more percent length of the blade is in use in a shorter blade. The longer blade might not all get used, leaving you sharp areas.

 

[TheEdge01]

Smaller knives may not be called upon as often to handle larger tasks but they need to be equally sharp. I’m sure it will dull like any other larger or smaller blade if used in the same manner.

 

[danbot]

Leverage possibly, torque not really, unless the longer knife's bigger-diameter handle might increase the torque.

True.
I would think that levering or torquing the blade would be accidental anyway, but a longer knife will make it a lot more possible. It's pretty hard to accidentally twist a 3 inch blade for most reasonable tasks.

 

[Mo2]

I use 3-4" blades to cut ungodly amounts of cardboard. Yes I need the edge retention in a small knife.

If it were used as edc lightly like some folks do... Then it's not needed as much.. . But that can vary depending on so many variables. Say Christmas when cutting up the boxes from presents... Aus8 will need to be sharpened in between the job where 20cv wont need sharpening for a long while.

10" knives and above need to be good enough for chopping and batoning. So I'd say toughness more than edge retention. But a good compromise is 3v.

 

[marrenmiller]

I was thinking, if a blade made of some steel is only 3-4" long wouldn't the cutting forces near the tip be much less than a blade 10" long. If they are then wouldn't a longer knife dull more quickly do to edge damage? Basically can shorter knives get away with lower quality steel more than long knives?

Does size matter?

Why would the forces be greater? You're not really using the knife as a lever, you're just slicing with it.

Plus, I don't see how edge damage would be related to wear resistance in this fashion. If anything, I'd assume that the shorter knife could benefit from higher wear resistance because there's less edge in total to degrade against during normal cutting.

 

[danbot]

Why would the forces be greater? You're not really using the knife as a lever, you're just slicing with it.

Plus, I don't see how edge damage would be related to wear resistance in this fashion. If anything, I'd assume that the shorter knife could benefit from higher wear resistance because there's less edge in total to degrade against during normal cutting.

Bit if all things are equal. ie: same steel, same heat treatment, and you are using the entire edge while slicing cardboard, they should both dull at the same rate. So size wouldn't matter.

 

[Ten_Mile_Knives]

Leverage possibly, torque not really, unless the longer knife's bigger-diameter handle might increase the torque.

That is definitely true, I wonder which is more damaging; torquing a blade axially, or leveraging it laterally? I'd be inclined to say torque is worse, it puts force on the thinnest part of the edge that is embedded in what is be cut. Whereas with leveraging the blade side to side would (I think) lead to a warp or wrinkle at the instead of a roll.

True.
I would think that levering or torquing the blade would be accidental anyway, but a longer knife will make it a lot more possible. It's pretty hard to accidentally twist a 3 inch blade for most reasonable tasks.

Agreed, cutting task or cut type aside a longer blade makes edge -dulling mistakes easier.

 

[Mistwalker]

I use my smaller knives a lot more than my big ones. So to me edge retention and abrasion resistance is more important on my edc knives than my camping and outdoor knives.

 

[Peter Hartwig]

I would think that edge retention might be more important to the small. The might is due to not knowing the tasks each is going to be expected to do. Most if not all tasks for the small will need a good edge. Not all tasks for the large need a good edge and some will destroy an edge. Hard for me to think of this apples to apples-they are different tools to me and their uses are different.
My way of thinking based on how I use them

 

[PirateSeulb]

I think it is all about purpose but to me small knives share much of the same purpose which is mostly going to involve stabbing/piercing and slicing. A Longer blade is more likely to be used for chopping which you want it to resist rolling and chipping if it will be used to chop more than edge retention, or at least I would, so while size might impact use use dictates prioritization of steel attributes.

 

[marrenmiller]

Bit if all things are equal. ie: same steel, same heat treatment, and you are using the entire edge while slicing cardboard, they should both dull at the same rate. So size wouldn't matter.

Why would they dull at the same rate? You're dragging the entire edge along a material to produce the cut. You may need to do that significantly more frequently on a shorter knife to produce the same effect (a given length of cut along a piece of cardboard). Hence, more edge degradation per unit length, with all other things being equal.

If you're just pushing the knife through and the cardboard rides along the same location on the knife each time, then I would understand your point. But even then, you'll arguably have more ability to keep cutting with a longer knife of the same material, because you have physically more edge to dull in this fashion.

Either way, the logical conclusion is that a smaller knife might benefit from higher edge retention to make it perform comparably to a larger knife.

 

[danbot]

Why would they dull at the same rate? You're dragging the entire edge along a material to produce the cut. You may need to do that significantly more frequently on a shorter knife to produce the same effect (a given length of cut along a piece of cardboard). Hence, more edge degradation per unit length, with all other things being equal.

If you're just pushing the knife through and the cardboard rides along the same location on the knife each time, then I would understand your point. But even then, you'll arguably have more ability to keep cutting with a longer knife of the same material, because you have physically more edge to dull in this fashion.

Either way, the logical conclusion is that a smaller knife might benefit from higher edge retention to make it perform comparably to a larger knife.

Good point.

 

[marcinek]

True.
I would think that levering or torquing the blade would be accidental anyway, but a longer knife will make it a lot more possible. It's pretty hard to accidentally twist a 3 inch blade for most reasonable tasks.

True. You're not really supposed to do either.

Now if you took your small fixed blade, and rehandled it using a large dinner plate or bicycle rim...then you could get some torque!