CRKT Point Guard


A shot from the CRK&T webpage on the Point Guard :

Point Guard

This one :

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The review consists of :

Description

The CRKT Point Guard has a drop point blade stock ground from 420J2 stainless steel hardened to 54/56 HRC. It weighs 120 g with a 3.125" long blade, the OAL is 4.75" when closed. The handle is a massive 0.5" thick with 420J2 double stainless steel liners, a 6061 T6 hard anodized aluminum back spacer and Zytel scales. The knife has a liner lock with LAWKS safety latch and a ball detent and opens with use of a thumb disk. The blade has a high flat grind and the edge is 0.020-0.030" thick ground at 20 +/- 2 degrees per side.

stock work

The Point Guard could not shave smoothly but could scrape some hair from the arm. On light thread it took 159 (11) g to make a push cut (a replacement had almost the same thread cutting ability with 157 (2) and took 0.85 (11) centimeters to slice light cotton under a 200 gram load). Cutting on 3/8" hemp it took 55 +/- 2 lbs on a push, no aggression on a draw.

The point has a 1.3" long taper with the blade 0.75" wide at back of the point which tapers at 3.0 degrees. This produces a slim point which with a 50 lbs push sinks tip 174 +/- 3 pages into a phone book, with a hard stab (icepick grip), the penetration increases dramatically to was 560 +/- 7 pages.

On birch hardwood it took 18.5 (3.1) slices to make a point and 75 (3) lbs to split the same section on a smooth push. Cutting television cable the Point Guard took 60-64 lbs and was undamaged through twelve cuts.

sharpening

The main purpose of this knife was to benchmark the steel, which at AISI 420 stainless is one of the lowest carbon steels used in cutlery, generally promoted for high toughness and corrosion resistance at the cost of low hardness and wear resistance. With a belt sander the edge on the Point Guard was reground to under ten degrees per side. The steel worked easily, however sharpening was problematic as the even on the flats of the ceramic Sharpmaker hones it would just burr from one side to the other and was difficult to get a crisp edge.

Edge retention

On 3/8" hemp with the Point Guard sharpened to the 20 degree settings on the medium Spyderco rods, rope was sliced on a two inch draw (away), unsupported, no cutting board. The Point Guard made the first 64 cuts with strong aggression, during the final 64 cuts, the blade was slipping and it was becoming difficult to make clean cuts. After the final cuts, the knife could no longer do fine cutting, could not even slice stiff paper.

Slicing 1/4" ridged cardboard through three centimeters of blade with the edge profile at 15 degrees included, freehand sharpened on a 600 grit DMT benchstone, the edge retention of the Point Guard was well behind a several other blades which were harder and more wear resistant. It also blunted in a different manner compared to the higher alloy blades which tended to have a more dramatic nonlinear blunting responce .

However with the edge sharpened at 600 grit aluminum oxide, the "fine" side of a cheap hardware store stone, and the same cutting repeated, the performance of the Point Guard was much improved and while it was still out cut by harder and more wear resistant blades, all knives could cut a massive amount of cardboard. Over 50 meters were cut with each blade and the knives were still cutting it well, the cutting was terminated just due to lack of cardboard. The average of two runs :

The numbers :

Slicing edge retention of the Point Guard, M16-14Z, and Temperance, on 0.25" cardboard, cutting with a 3 centimeter draw, edge set at 7/9 degrees, no microbevel. Results given are the edge lengths in centimeters needed to cut the cotton times 100 for ease of comparison.
Cardboard Point Guard M16-14Z Temparance
420J2 AUS-4A VG-10
meters 54/56 55/57 59
  0.0   32 (2)   34 (3)   33 (1)
  0.9   59 (3)   43 (3)   43 (4)
  2.7   74 (2)   69 (3)   53 (3)
  6.3   91 (4)   83 (4)   70 (3)
13.5 121 (6) 116 (6)   93 (6)
20.7 155 (6) 155 (7) 113 (7)
27.9 168 (6) 168 (6) 140 (5)
42.3 217 (6) 200 (9) 175 (7)
56.7 276 (9) 230 (9) 196 (9)

Handle ergonomics and security

The Point Guard is decently ergonomic, with better than average clip ergonomics. The clip curves gracefully with no squarish points to cause excess discomfort. The very aggressive cutouts across the lock and at the top of the handle are very secure but high in discomfort, they are not optomized for extended cutting but rather brief periods where high security is desired.

Lock

The liner is secure under white knuckling and light spine whacks, but it easily disengaged under wrist torques. With the LAWKS system engaged it is near impossible to disengage the lock under torques, however spine whacks hard enough to dent the edge on a piece of birch readily cause the lock to release. Harder impacts, still wrist action, through a 90 degree angle will collapse the lock even with the LAWKS safetly catch engaged. The LAWKS system doesn't break and it can be hauled back up.

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Update : A replacement from CRKT had the edge geometry and initial sharpness and cutting ability was consistent. To check the LAWK's the liner was moved to the far left with the LAWK's engaged. The point of the knife was then pressed into a piece of hardwood on a scale. Imediately the entire handle of the knife started to bow. The liner is the main source of strength for the handle and when it bent the handle followed with it. It was so weak that by hooking the thumb across the top of the handle and by pressing down with the index finger against the top of the blade on the back cause the handle to visually bow. On the scale, at 25 lbs against the point, the liner had moved all the way to the other side and also twisted down as it is skeletonized and thus could not be unlocked by hand.

Overview

With the initial edge profile obtuse edge profile, the Point Guard could cut up knots in woods, thick plastic and pop and tin cans. The knife went blunt quickly on the metals but resisted visible damage well, no damage to the tip opening cans of peas and tins of apple juice. The Point Guard was decent in the kitchen as a paring knife or small utility blade. It peeled potatoes, cut onions and sliced up meats with ease. The steel resisted staining even when exposed to acidic juices and the handle was comfortable and secure. However it was readily contaminated with debris due to all the cutouts and not trival to clean.

In regards to prying and other heavier work, the Point Guard has good ductility so the takes a large bend before breaking however the low softness does allow it to bend easier. It was inserted 1/4" in a piece of spruce and was levereged sideways until it broke the wood out cleanly. It was then drove in 1/2" and leveraged sideways until it was flat with the wood. The point took a 25 degree set but didn't break. The lock held up fine, no blade play. The blade was straightened by prying in the opposite direction.

The Point Guard has an ergonomic handle, secure and strong lock, with a decently efficient blade profile. The initial edge profile is a little thick and obtuse and the NIB sharpness a little low, however with some work the knife can be made into an efficient cutting tool. The lock could however use some both, both samples of the knife had significant defects and similar problems have been reported on other CRK&T blades.

Comments and references

Comments can be sent by email to : cliffstamp[REMOVE]@cutleryscience.com or posted in the following thread :

More information can be seen on the CRK&T website.


Last updated : 03 : 10 : 2006
Originally written : 04 : 01 : 2005
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