Behind-the-edge (BTE) thickness

sharp_edge

sharp_edge

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I understand if a knife is too thin BTE, the edge can be chipped when too much lateral force is applied. But I feel many folding knives currently in the market are too thick BTE, e.g., most ZTs and regular Hinderer XM-18s. I think they all can be thinner BTE while still maintaining reasonable strength. For example, the gen 3 Hinderer Eklipse Bowie that I recently picked up is an exception. The blade still has the same thickness on the spine as the regular XM-18 but the BTE thickness is about the same as that of XM-18 3.5" Skinny Slicer.

Do many people really like a thick edge on a folding knife (again I am not talking about thick spine) or is it mainly because knife manufacturers want to reduce their warranty work?

Edit: added some drawings to show while the spine thickness and blade height do not change, there could be quite different grinds of the blade and hence different slicing/cutting performance.
KQq47MK.jpg
 
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I can see valid arguments (up to a point) for thin or thick blades bte.

My zt0452 is sublimely slicey due to being thin, especially for a zt. But I wouldn't expect it to put up with how I treat my fixed blade, not even close.

In that role, it works well. If I'm not carrying my fixed, there's more argument that a stouter folder can close the gap somewhat.

It really just depends on what you want from it. There's not a wrong answer, just tradeoffs.

Personally, I like thinner folders.
 
The width of the edge at the edge shoulders is probably the most under-rated aspect of knife performance.

But you do have to match the BTE thickness with the steel and the tasks at hand.

Probably the biggest advantage of the super steels is that you can go with a much thinner, high-performance edge and not suffer any edge damage. It's really a waste to put a .030 inch edge on a high-end steel edge.
 
It depends on the model and the intended use of the knife. ZT and Hinderer tend to favor the "hard use" side of the market. TRM is at the opposite end, favoring thinness and cutting ability over toughness.
 
Using a Manly Wasp (S90V version) was a wake up call for me. It shows how thin you can go, and you can judge for yourself if you damage it or not during your daily tasks. There’s so much cutting ability left on the table by most knives being thick bte.
 
Twindog said:
The width of the edge at the edge shoulders is probably the most under-rated aspect of knife performance. But you do have to match the BTE thickness with the steel and the tasks at hand.

It's really a waste to put a .030 inch edge on a high-end steel edge.
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I have owned a LOT of folders and fixed blades, and I do NOT care for cheap knives;...some do...that's fine.
What I have commonly found is 0.030-0.035" thickness behind the edge; generally at the grind shoulder.
This is easy for manufacturers and is okay for a woods knife, but is of little use for casual EDC.
It has been repeated many times that "GEOMETRY IS EVERYTHING."
If you want your decent grade of carbon or stainless blade to cut and slice for casual use at home and around the home...a BTE thickness of 0.015" (or less) will make you smile and smile and smile, and you'll wonder how you ever managed
with those earlier pry-bars in your collection.
 
OrangeBlueOrangeBlue said:
It depends on the model and the intended use of the knife. ZT and Hinderer tend to favor the "hard use" side of the market. TRM is at the opposite end, favoring thinness and cutting ability over toughness.
Click to expand...

This is also often what I hear. But what kind of hard use are we exactly talking about with a folding knife? I know some people will say break doors, stab car hoods, use as a ladder/steps to climb cliffs. But do people really/ever do any of these using their folding knives? Even for fighting a mad racoon, thinner edges than what they currently are should reliably do the work with those folding knives.
 
sharp_edge said:
This is also often what I hear. But what kind of hard use are we exactly talking about with a folding knife? I know some people will say break doors, stab car hoods, use as a ladder/steps to climb cliffs. But do people really/ever do any of these using their folding knives? Even for fighting a mad racoon, thinner edges than what they currently are should reliably do the work with those folding knives.
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Rick Hinderer was a firefighter/EMT, so I imagine "rescue" things. Honestly, I think "hard use" for folding knives is more about "will this knife be subjected to lateral forces" than anything.
 
sharp_edge said:
Do many people really like a thick edge on a folding knife (again I am not talking about thick spine) or is it mainly because knife manufacturers want to reduce their warranty work?
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Talking about RKH, I think he just makes what the market expects, hard-use, fire-fighter, bla, bla ... if you look at Rick's custom grinds, they all are hollow, and look like very good cutters. While I cann't afford those, I had other people regrind a couple of my Hinderers, and they are scary cutters. Shown these before, hope you don't mind the repost ...

i-69CxM9W-X3.jpg


i-5TsmgFC-X3.jpg


i-BwdhmzC-X3.jpg


BTW, agree with you on the new Eklipse Bowie. The other (regular, non-skinny) Hinderers that cut well in practice are the Wharncliffes. BTW, one of the reasons that I like the Fulltrack is that the stock is thinner, than say in the XM-24 (non-skinny).
 
Dangerously said:
Using a Manly Wasp (S90V version) was a wake up call for me. It shows how thin you can go, and you can judge for yourself if you damage it or not during your daily tasks. There’s so much cutting ability left on the table by most knives being thick bte.
Click to expand...

For reference, that knife (manly wasp) is claimed by mfg to have a 0.24cm thick blade (at the spine). That is ~0.094in. A spyderco pm2 has a 0.14in thick spine at the thickest point, which is also much higher ground than the manly. Five one hundreths is not much steel.

Arguably, they have very close geometry at the edge, given the height of the grind of the pm2 being higher.

The pm2 is a very popular knife.
 
co556guy said:
For reference, that knife (manly wasp) is claimed by mfg to have a 0.24cm thick blade (at the spine). That is ~0.094in. A spyderco pm2 has a 0.14in thick spine at the thickest point, which is also much higher ground than the manly. Five one hundreths is not much steel.

Arguably, they have very close geometry at the edge, given the height of the grind of the pm2 being higher.

The pm2 is a very popular knife.
Click to expand...
I don’t quite get it. You are listing the thickness of the spine of the knife as an indication of the thickness behind the edge.

This doesn’t make any sense to me. You could take 10 PM2s and grind a full flat primary grind that has a different thickness behind the edge on each one. One has nothing to do with the other.

The only way to know if they have the same thickness at the edge is to measure it, not guess at it.
 
Thinner is not always better. That's a trend, don't believe it. There's a reason a splitting wedge and a carpet knife have vastly different edge geometry.

If we are applying this to folders, I personally like to either reset the edge angle to 17 for slicers and 20 for general carry.
 
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