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Evaluating A Custom Knife by Darrel Ralph

FOLDERS:

  1. Fit and finish inside and out. Look in the front end of the knife, at the stop area, and the linerlock ramp -- fit and finished? On a lockback, is the cam area and blade-end finished? Look inside, is the knife clean? What do you see?

  2. Test for any wobble of the blade at the pivot. This is often considered an important test of a folder's construction especially if it is knife which will see use. Take the pressure off the liner (or backspine for lockbacks) while the blade is in the fully opened position and wobble the blade. This is the only accurate test because if the liner or lock is engaged you can't tell if the blade pivot is precise. On autos you may find a very small amount of play while on a linerlock or most lockbacks there should be none that you can feel. However, pin-together lockback folders will have a small amount of blade wobble with no load on the lock. This is due to the fact that there are no washers, and a zero-tolerance metal-to-metal fit will "gall" or bind. Generally the customer expects a very light & smooth action. Most expect the blade to fall when the knife is held upside down and the lock released, yet to still have minimal blade play, thus making use of a washer impossible. So makers have had to adjust their knives accordingly. As for linerlocks, they can and should be made with near zero side-play given the availability of the synthetic washer material we have today. One thing to take into consideration when looking at a previously owned knife is that the former owner may have loosened the pivot screw so they could "sling" the blade open, thus compromising the makers original "specs" for blade play.

  3. Does the knife open smoothly? A good pivot opens smoothly, with very little friction (given the appropriate tension adjustment at the pivot); there is no wobble and no "ragged" feeling to the motion of the blade.

  4. Detent (linerlocks). Is the knife blade detenting? Does it stay shut under normal usage?

  5. The blade should be positioned so it is centered with respect to the frame when it is closed.

  6. Lockbacks should stay shut when hung upside down. The degree of stiffness in the opening action is a personal preference and needs to be considered when judging the knife. In addition lockback knives, unless they are designed especially to not do so, should have an almost seamless fit where the blade meets the backspine (locking bar) when they are opened.

  7. Blade grinds can be another area to evaluate closely. In the choil area check that the grind radius matches on both sides of the blade. Hold the knife up to the light with the edge towards you and see if the grind lines match as they come down from the blade. Occasionally you'll see that the choil grinds will match but the radii sweeping from the grind downward won't. Also look at the tip. See if the grinds are the same and the blade is straight and the clip matches on both sides.

  8. Liner lock-up and fit. For lockbacks does the lock wobble up and down? Will either unlock with pressure on the handle? Accidental unlocking is of more importance to a "using" knife than for one which is intended as a display piece.

  9. Beware the term "looks like it will fail" when discussing the lockup of a liner. Locks have been known to fail that are on the left edge of the blade, on the center of the blade or all the way across the blade. Assuming the lock engages the blade by at least the thickness of the liner then there are two things that make for a positive lockup: (1) correct tension on the lock , and (2) a 90 degree angle on the lock face & proper angle on the blade. If these two things are correctly done the lock will hold, if not, the lock will fail no matter where it sits on the blade. So the only way to know is to apply pressure to the blade and see if it holds. Every customer has a preference as to where they want to see the lock.

  10. Check for sharp edges and finish of the screw slots.

  11. How clean and oil-free is the knife?

 

Fixed blades:

  1. How well is the guard fitted to the handle? Is it square with respect to the blade?

  2. Check the blade grinds as above. Daggers are often challenging in this regard.

  3. Balance. Balance is especiually important in a "using" knife and strongly contributes to the effectiveness of the knife (or sword). Many believe the balance point should be around the guard while, for swords, from the guard to 10 inches max. in front of the guard depending on length. If you are having a knife ( or sword) made then make sure you discuss with the maker your preferred balance position and whether he, the maker, would make any suggestions based on his experience.

On Both:

  1. Inspect the steel for flaws. A hand-rubbed finish should be a continuous set of lines with no fuzzy brush marks. Machine satin-finish should be consistent over the entire surface. In no case should you be able to see grind marks underneath the finish.

  2. Design: Is the knife a picture or does it have stopping place to the eye? Perhaps I can explain this a little. Many people see a knife-maker as just a guy who makes knives. But to make a knife where the "lines" flow artistically requires more than than just the normal "logical" thought that we use for most things. I found a book which left an indelible impression on me and let me succeed in learning to draw. The book is "Drawing on the Right Side of the Brain : A Course in Enhancing Creativity and Artistic Confidence by Betty Edwards (ISBN: 0874775132)". There are two aspects to appreciating the design of the knife: one is the overall "picture" the knife makes while the other is the individual components and lines which draw your eye from one component to another. With a well-designed knife these two aspects work in harmony to form the overall view of the knife. With some knives a technique I like to use is to hold the knife upside down. This way, if the knife doesn't "look" like a knife, you fool your brain into not looking at the knife logically but rather artistically, as an object. Do the lines guide your eye to the different elements of the knife? Do all the elements come together into a single pleasing, picture? If this is true then the design has been well thought out and well executed.

  3. Check the blade grind thickness from side to side. The edge angle should be consistent from side to side. The point should be very sharp with no burrs on the top or sides of the edge. There are several types of grinds and each should be evaluated individually. Hollow grinds should be thick enough to make for a strong cutting edge . Flat grinds should be flat with a small "apple seed", i.e. a convex shape, on the edge. This keeps the edge strong. Another grind is the saber grind which is a convex-type grind . This is the strongest type of grind, for example some swords and most axes use this type of grind, but the drawback is this grind is difficult (impossible) to sharpen by hand without flattening it. To produce a true convex grind requires a belt-grinder with the belt loose (slack). The easiest grind to sharpen is the hollow grind but is the weakest of the three. I am a believer in the flat grind. It's in the middle of the other two and serves well for the collector, however, the grind should meet the requirements (aesthetic or practical) the owner has for the knife.

  4. Has the maker chosen a Damascus steel for the knife? There are two main things to consider when evaluating Damascus steel: the overall pattern/appearance and whether there are serious flaws in the welds. If you like the pattern and the way it is finished then small welding flaws should be overlooked since no piece is going to be flaw-free. Specialty Damascus can be expensive to make; a maker can easily spend a hundred hours turning 7 pounds of various metals into 8 ounces of finished Damascus. So don't be surprised when high prices are being asked for steels from well-known leaders in the field or for particularly exotic or work-intensive patterns. Since the appreciation of a particular piece of Damascus is so personal it is hard to give guidelines beyond "that which appeals to your particular taste". In general the steel should not appear "muddy", that is, the pattern and the etching process (if any) chosen should leave the piece with a crisp look. Some people prefer a subtle pattern, others prefer a flashy one. Some examples of well-known makers of quality and/or cutting-edge work are: Don Fogg, Steve Schwarzer, Hank Knickmeyer, Barry Gallagher, Shane taylor, Rick Dunkerly. When looking at mokume (which is a damascus made from non-ferrous metals) watch for flaking and peeling of the layers. Several patterns are available so, once again, it is up to the collector to determine what they like as far as appearance goes.

  5. Choice of materials: Are these the right materials? Do they go together well? Evaluating the material chosen for the handle and how well this fits with the overall view of the knife is, again, a personal preference. In my view the materials chosen for the knife should go well together, i.e. fit with the motif of the knife and, for me, add a bit of zing. I do not use many woods, but when I do I prefer burled types if they are available. As for synthetic types of materials; I find they all cost about the same so I am not partial to any particular one. For a utility type knife, G10, micarta and carbon fiber all make great handles.

    Pearl: there are many types and grades of pearl. All pearl should be skin free (the dark scaly material, on the ends mostly); look for cracks and worm holes. Most types of pearl will show a "shimmer" effect which is often appealing in the finished handle.

    Black-lip pearl should be black with cobalt-blue, red, purple and a small amount of white for colors. Some light spots are acceptable but, in general, it should be mostly a variety of colors.

    Gold-lip pearl should be gold with very few light spots. The best gold-lip I have seen is either solid gold or gold with some other color present. The colored type seems to be a bit lighter.

    White pearl, in the presentation grade, is usually very white, sometimes with clouds. I prefer the type with some color over the pure white type since I feel it gives the knife a better over all look. This type is usually grade A without cracks.



  6. Blade-to-handle ratio. Does the blade look proportional to the handle?

  7. How does it feel in the hand?

  8. Is the blade sharp?

  9. Examine the file work (if any). It may look good at first glance but after further inspection it may be way off. Does it have a theme? For some knives the maker will carry a theme throughout different aspects of the knife's decoration (including the file work).

  10. Blade heat treat. Primarily one has to go by the knife-maker's reputation, but, if you own the knife you can test the edge using a small brass rod. This description is courtesy of Steve Harvey: I use Wayne Goddard's brass rod test. I press the edge sideways against the side of a 0.25" brass rod. If the edge is properly tempered, you should be able to see it flex around the rod, and return to straight without deforming (too soft) or chipping (too hard). I learn a lot about the steel from sharpening also. A burr should not form too easily, or be too large. Also, if the burr is very elastic, and tends to just flop side to side rather than getting harder to feel as you use lighter strokes or finer grits, that is a bad sign. Usually this is after the sale, but if you paid $400 for a blade that won't cut or hold an edge worth a darn, it will give you something concrete to tell the maker.

A word on sharp. A blade does not have to shave to be sharp. A meat cutting edge is better if it is just at the point where it's biting but may not yet shave. It will cut longer this way. I have done tests that prove that a knife sharpened like this cuts longer than one that is shaving sharp. I am not discounting the shaving edge. But a knife should be sharpened for the job it is meant to do. A dagger is meant to puncture not cut paper etc.



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