Buck Strider/Solution

Actually we use a Tinius Olson that measures in pounds of force.

I don't know the exact measurements they use (they follow DOD testing criteria), but the tip of the ram is on about the halfway point on the blade. I've watched them do about twenty myself. Its pretty cool. Very loud bang when the thing finally goes.

Of course the closer you get to the tip while prying the number can change. Thats why as a user, one must know how to pry with a knife when necessary. I have found that as you pry the hatch (or whatever you are prying) slide the knife further in as you pry to keep as much "meat" of the blade handling the work. Twisting the knife while prying isn't a wise idea since it may damage your edge and accomplishes nothing towards your goal.

Its not super relevant but I just wanted to expand on your 200 lb comment above.


-Josh
 
J Rummerfield said:
Actually we use a Tinius Olson that measures in pounds of force.
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That is why machines can't do science. You don't simply use the units of the machine, but have to understand what is causing the break and how to measure that quantity.

In this case you are rotating the blade so you are looking at a torque
[*]. Take the force and multiply it by the distance from the point of application of force to the point at which the blade is held.

Or simply cite both of them of course. Noting just the force is meaningless because you can break a blade with any amount of force depending on where you apply it, so it is meaningless.

You also want to look at the plastic limit, where the knife takes a set, if any as it is likely to be a shallow window in stainless and other non-ductile steels. Both angles and torques are informative.

I have found that as you pry the hatch (or whatever you are prying) slide the knife further in as you pry to keep as much "meat" of the blade handling the work.
Click to expand...
This also makes it much harder for you as you are inducing a torque disadvantage.

I dug a hole with it today, large enough to fit a 1 gallon bucket in. The edge chipped readily in the rock contacts, about 0.5 mm deep, three large visible chips, the tip also fractured, lost about a mm. No fine cutting ability on the edge used to dig, could not even score ropes for example.

This was semi-stressful digging. It was not going really light trying to concentrated impacts on the spine, which make it easy on the knife but hard on you, but nor was it raising the knife up and slamming it hard like a pick, it was more poking than actual stabbing as you would with an actual pick.

Took 10 minutes to fully resharpen the blade, the edge was rest with an x-coarse waterstone (7.5 minutes), then honed on a 1000 and then microbeveled on a Sharpmaker, to a hair popping level of sharpness. Note the chips were not removed, this would have lost too much metal, the rest of the edge was just brought back to full sharpness.

The tip was still damaged, penetration was 58 +/- 5 on phonebook now, less than half of optimal. It would remove another half a mm of edge to bring the tip back in line, not sensible, if I wanted to fix it I would sweep the edge up.

Not bad considering the acute edge grind, but the chipping is not what I would want in a blade going to be used for digging on a semi-regular basis as too much metal is lost in sharpening, and it indicates a lact of ductility for prying. This is more what I would use for such work :

http://www.jenseneliteblades.com/evosurv.htm

Has a nice shovel tip, and is offered in simply carbon steels, much more suitable for prying and impacts. I might look at that the summer, interesting design, similar to the Tracker which I am curious about especially after hearing reports about how it out chops GB axes, which I am a little skeptical of.

[*] You can also look at it from a stress/strain perspective, but torque is easier to relate to for most people.

-Cliff
 
My brother has been using this alongside the Gerber Silver Trident

http://www.physics.mun.ca/~sstamp/images/gerber_silver_trident.jpg

-solution is solid, pull ups through the main body of the blade no problem, 190+ lbs

-cutting ability is above average for shallow work, very good for a "tactical"

-handle is really boxy and uncomfortable

-chopping ability is low for its size, handle doesn't work well in extended grips.

The Gerber is directly prefered for most cutting and way ahead for chopping, its only problem is the primary serrations which prevent whittling and other such push cuts, and trying to do such work with the primary plain edge creates a huge leverage disadvantage.

He hated the top guard on the Gerber and quickly sawed it off, I'd have done the same, great if you want extreme security but really limit grip versatility.

-Cliff
 
My brother bought over a huge pile of birch hardwood to use as stock testing, 5/8" thick of various widths. While I was doing some cutting comparisions, I watched him start to fool with the Solution as he was talking about the performance from the work he had done in the last week or so.

He chopped the solution into the wood, torqued to the side and a huge piece broke out. He then did it again with the same results on another area of the blade. Note the penetration into the wood was low, mainly as the handle ergonomic issues prevented serious swings. For similar reasoning it wasn't heavy torque, just wrist rotation :

http://www.physics.mun.ca/~sstamp/images/solution_bits_top.jpg

http://www.physics.mun.ca/~sstamp/images/solution_bits_side.jpg

The Solution was then drove into a spruce log and walked on, with 1.5" of the blade in the wood it easily took ~200 lbs on the handle. However a light pop from a hammer to loosen it and the blade broke in half and another piece broke out of the edge up by the handle, not in the impact area, just from the vibration in the blade.

http://www.physics.mun.ca/~sstamp/images/solution_cracked.jpg

-Cliff
 
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