Canadian Woodworking

Choose the right knife for the job

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No one knife does it all. Depending on the task at hand, you may need versatility, utility or durability from this indispensable tool.

Author: Carl Duguay

Let’s take a moment to give thanks for the humble knife. It’s arguably the most widely used hand tool in the world – indispensable in the workshop, at home and anywhere in-between. For woodworkers and avid DIYers four broad knife styles will be of interest: utility knives, pocketknives, multi-tool knives, and a more specialized category called marking knives. While in theory you can get by with a single type of knife, why would you want to?

Utility knives – light duty, inexpensive and disposable

When it comes to general manual work, tradespeople, renova­tors and DIYers are likely to grab a utility knife. They’re useful for a wide range of jobs around the home, shop and jobsite from cut­ting drywall and rigid foam insulation to slicing carpeting, stripping electrical wires, opening cartons and sharpening pencils. You don’t have to worry about damaging blades because they’re replaceable and relatively inexpensive. While there are dozens of styles avail­able, they can be roughly grouped into two categories: those that have a trapezoid-shaped blade (the traditional utility knife, also called a box cutter) and those that take a segmented blade (most often referred to as snap-off knives). The blades of either can be made of carbon steel, high-speed steel or carbide.

There are both folding and non-folding (straight) versions of trap­ezoid blade knives. These blades have a pointed tip on each end that projects about 3/4″ when inserted into the knife. You can also get hooked blades. When one end gets dull, just turn it end-for-end, effectively giving you two cutting edges. Some models have belt clips or can store extra blades in the handle.

The Stanley STHT10424 ($10, stanleytools.ca) is a folding ver­sion that has a push button for easy blade change and locks into an open position when unfolded. To close it you press against a liner lock and fold it back over. The Milwaukee 48-22-1505 ($29, mil­waukeetool.ca) is a folder that incorporates a wire stripper, fold-out 1/4″ bit holder and bottle opener. The blade also locks in the open position. Both knives have tool-free blade change and a belt clip.

Folding Utility Knives
Folding utility knives offer a fair bit of strength and their ability to fold makes them easier to have nearby. Since their blades are replaceable, you don’t even need to sharpen them.

One of the major advantages of snap-off knives is that a fresh edge is only a snap away. A knife with a narrow blade will have more segments; wider blades have fewer segments. You can extend the blade and leave the knife locked when you need to make a deeper cut. However, segmented blades are usually thinner and therefore more flexible than trapezoid blades, and can easily break when extended. This is especially true with narrower blades. Because segmented blades are thinner (1/64″) than trapezoid blades (3/128″) you can use them in a pinch to lay out cut lines for joinery. The main challenge with using these knives in this scenario is that, because the knives were sharpened to a double-bevel rather than a single bevel, they may not be as accurate if you’re referenc­ing off a square or ruler.

A Quick Snap
It’s often possible to remove the non-cutting end of the knife handle to assist with snapping off the dull portion of the blade. A pair of pliers will also work.

The Milwaukee 48-22-1960 ($5, milwaukeetool.ca) with a 9mm wide blade has 12 blade segments and is better suited for light-duty cutting tasks. You break off dull blade segments with pliers. For heavier duty cutting there’s the Stanley FMHT10592-0 ($20, stanleytools.ca). It has an 18mm wide blade with six segments and features an integrated blade-snapping mechanism along with a wheel lock to set blade extension.

Snap-Off Utility Knives
Although it’s easy to obtain a sharp edge, snap-off utility knives generally come in two sizes: small and large. The smaller version is great for light-duty tasks around the shop and home, while the larger version is fairly robust.

Pocketknives – more/durable, greater versatility

One of the most ubiquitous knife styles, pocketknives (a.k.a. jack knife, folding knife, flick knife, everyday carry knife), are versatile, lightweight, strong, durable and compact. There are hundreds of different models available in a wide range of blade and handle options. They have thicker and longer blades than utility knives, making them much more durable for a wider range of tasks.

Pocket Knives
Here are three examples of everyday carry knives, each with a slightly different blade and handle style. There are a number of locking mechanisms, too. Select a knife you find easy to extend and retract, that fits comfortably in your hand and has the right style blade for the work you intend to do.

Blades can be made of carbon, stainless or tool steel. Carbon blades (such as 1095, K720 and 420HC) are easy to sharpen and hold an edge well but are prone to corrosion. Stainless steel (includ­ing CPM 154, AUS and 8Cr13MoV) is essentially carbon steel with chromium added to prevent corrosion, which has the effect of reducing overall blade strength somewhat. Tool steel contains vari­ous elements such as titanium, molybdenum and vanadium that give it good strength, hardness and wear resistance.

Most pocketknives have some type of locking mechanism to keep the blade from inadvertently closing and cutting your hand. Common types are frame locks (one side of the handle acts like a spring to keep the blade from closing), liner locks (similar to a frame lock except it uses the side of the handle’s inner liner) and back locks (a pivoting spine opens and closes the blade).

The shape of the blade is important for the kind of work you intend to do. For woodworkers the two most usable blade styles are Wharncliffe and sheepsfoot. The main difference between the two is that the Wharncliffe has a sloping spine and narrower tip, making it better suited for detailed work, while the sheepsfoot has a parallel spine with a blunt nose making it better suited for heavy-duty cutting.

Cutting Angle
The top blade has been factory ground. Due to its fairly steep cutting angle, the knife blade won’t cut if it’s too close to parallel with the workpiece. The lower knife has been honed on both sides of the bevel after it was purchased, so it will more easily take light shavings off a workpiece.

The Kershaw Leek Copper (#1660CU, kershaw.kaiusa.com; $185 at houseofknives.ca) is a slim folder, only 3/8″ thick, with a 3″ CPM 154 stainless steel modified Wharncliffe liner locking blade, a copper handle that develops a lovely patina and a belt clip. For more aggressive work, the Gerber Cleaver (gerbergear.com; $218 at warriorsandwonders.com) has an aircraft-grade aluminum han­dle, 20CV cleaver-style liner locking blade with an intuitive finger flipper opening mechanism. This knife excels at cutting, slicing and chopping, making it better for heavy cutting jobs. If all you want is a bare bones folder, there is the Stanley Skeleton Frame (#STHT10253, $20, stanleytools.ca). It has a 5/16″ thick stainless-steel blade with a back lock and weighs a mere 73 grams (2.6 oz.). It doesn’t have a belt clip nor does it hold an edge as well as the Kershaw or Gerber, but for the price it can’t be beat.

Multi-tools – the pocket toolbox

While a utility knife and pocketknife are restricted to one task – cutting – a multi-tool is a knife with one or more blades (often including a serrated blade and a saw blade) along with a selection of various tools that may include pliers, screwdriver, scissors, awls and bottle openers. Some are light enough to be carried in a pocket or attached to a belt with a pocket clip or carabiner. These gener­ally have three or four accessory tools. Others may have upwards of 20 different tools and are so heavy and bulky they need to be toted around in a sheath clipped to a belt or stored in a toolbox. Because of their functionality they’re especially popular with outdoor enthu­siasts, service technicians, renovators, tradespeople and the like.

Multi-Tools
Three examples of different multi-tools show how different these knives can be from each other. Look closely at what tools each multi-tool includes to make the best purchase for the work you plan to do with the knife.

At 3-5/8″ long and weighing only 3 oz., the Gerber Armbar Drive (gerbergear.com; $42 at warriorsandwonders.com) is about the same size as a pocketknife. It has a 2-1/2″ locking blade with a 2-1/2″ long double-sided screwdriver, awl, pry bar, scissors, bottle opener and mini-hammer. This is the model I carry with me most of the time. The Leatherman Free K4 ($135, free shipping, leather­man.com) at 4.5″ long and weighing 5.5 oz., is a full-size multi-tool with an integrated pocket clip. It has a hefty 3-1/2″ 420HC carbon steel blade, scissors, pry tool, awl, bottle opener, and Phillips and two slot screwdrivers. All the tools lock into place when opened, except the scissors. Plus, there’s an exceptional 25-year warranty. Both of these knives have a modified Wharncliffe blade shape that works well for general layout work.

If you do any amount of carving, whittling or texturing the Flexcut Carving Jack 2.0 ($179.95, Flexcut.com) is the knife for you. It’s 4-1/4″ long, weighs just 4.4 oz. and has a cross-etched, aerospace aluminum handle that prevents it from slipping in use. It has 1-1/2″ straight and Pelican (convex curved) blades, 3/4″ radius hook knife, straight gouge, gouge scorp and V-scorp, all of which lock into place. The blades are made from 1095 spring steel that are quick to sharpen and hold an edge very well.

Marking knives – for precision layout

If you make furniture or fine cabinets then you’ll likely want to use a marking knife (a.k.a. striking knife), which does a much better job of laying out joinery cut lines than a pencil. A thin, bev­elled blade slices wood fibres that create a micro channel for your saw or chisel to register against.

Marking Knives
Here’s a wide selection of marking knives that could be found in a woodworking shop.

These knives can have a cutting edge that lines up with the tip of the blade (the standard blade found on most knives) or a cut­ting edge that lines up with the centre of the blade (referred to as a spear point blade). Standard blades usually have two bevels on the cutting edge, but can also have a single bevel, either for left- or right-handed use. Spear point blades are single bevelled. Having only one side of the knife bevelled enables you to hold the blade flat against a straightedge for scoring cut lines. Spear point blades can cut in any direction. For working in tight spaces, such as when laying out dovetails, a narrow small-angled blade is a good choice. Generally, when using a marking knife, you should position the bevel side of the blade outwards, away from your straightedge.

Marking Knives in Use
Marking knives with a flat back can be used against a straightedge to leave a very accurately located marked line. This is because the flat blade back can rest flat against the edge of the layout tool and be held perpendicularly to the surface of the workpiece.

Making your own straight single or double bevel marking knife isn’t overly difficult. You can grind the blade from an old bandsaw or hack saw blade or purchase a pre-made blade. Grinding a spear point is a bit more of a challenge as you need to shape both the symmetrical tip angle and the side bevel angles. For years I used a #2 Chip carving knife ($19, leevalley.com) before I graduated to a spear point. It has an ergonomically shaped handle with a rather thin (9/128″) and short (1-3/8″) double-bevelled carbon steel blade that holds an edge nicely.

Marking Knife Tips
All of the marking knives have a double-bevel, spear point. These marking knives differ in their blade and handle dimensions, along with their handle shape and dimensions. Naturally, their looks might also play into what marking knife you buy.

Japanese spear point knives ($28.50, leevalley.com) are un-han­dled. They’re made of white steel (finely grained carbon steel) bonded to a softer carbon steel, which makes them easy to sharpen. They hold an edge surprisingly well. At almost 5/8″ wide and 7/64″ thick, I find them good for general marking, but too bulky for fine work. Overall length is 6-1/2″. The Pfeil marking knife (pfeil­tools.ch; $29.74 at kmstools.com) at 1/2″ by 1-5/16″ and 9/128″ thick is appreciably smaller. It has a K720 carbon steel blade that delivers good edge retention and is easy to sharpen. Overall length is 6-3/8″. Similar to the Pfeil in shape and size is the Lee Valley striking knife ($49.50, leevalley.com).

Keep It Simple
A simple marking knife, this option from Veritas has a thin blade and simple handle.

For fine work, the Czeck Edge Kerf Kadet II ($49.50US, czeckedge.com) and the Blue Spruce Classic ($74.99US, bluesprucetoolworks.com) are the epitome of elegance and func­tionality. The blades on both are honed and ready for use. The Kerf Kadet has a 5/16″ × 1-5/8″ carbide blade that’s only 0.029″ thick. In normal use the blade will likely last almost indefinitely with­out the need to be re-sharpened. I also like that the blade is very stiff; virtually no flexing in use. The Bolivian rosewood handle with machined bronze ferrule is comfortable and well balanced. Overall length is 7-3/4″.

The Blue Spruce Classic has an 11/32″ by 1-5/8″ high-carbon steel blade that’s 0.032″ thick. A unique feature is that the knife has a tool-less collet system that enables you to use other Blue Spruce collets, blades and scratch awls. The knife is a tad heavier and the curly maple handle is larger than on the Kerf Kadet, which may appeal to people with larger hands. Overall length is 7-1/4″.
If pricing is a factor there is also the Canadian-made Veritas workshop striking knife ($24.90, leevalley.com). It features an A2 steel blade and narrow, nicely contoured ABS handle. The blade is just under 1/32″ thick and 5/16″ wide, an ideal size for doing accurate, detailed marking.

Keep your knives sharp, otherwise you’ll likely begin to apply undue force – which can lead to poor-quality cuts and injuries.

Published:
Last modified: June 4, 2024

Carl Duguay - [email protected]

Carl is a Victoria-based furniture maker and the web editor at Canadian Woodworking & Home Improvement.


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