Quick cutting, long-lasting, economically priced rasps.
The rasp is an ideal tool to use when there is a lot of stock that needs to be removed, particularly on convex or concave surfaces, or where you need to quickly bevel or chamfer an edge. The technique I find easiest is to cut out as much of the rough profile as I can on the bandsaw, followed by shaping with one or more rasps, and then final smoothing with card scrapers or sandpaper as needed.
Not only do rasps cut quickly, they also provide a high degree of control and precision. Smooth cutting rasps provide a relatively clean finish, with minimal tear-out, even on highly figured wood. And, they’re quiet in use, which is an important consideration for anyone who works in a fairly small shop.
Once you’ve tried a rasp, you’ll find it indispensable for shaping chair legs and arms, spindles, guitar necks, oars, bows, tool handles, the edges of table tops, and sculptural pieces. Though it excels for work on convex and concave surfaces, you can also use a rasp for quick removal of stock on flat surfaces, for example, final fitting through tenons on trestle table legs.
Most woodworkers will be familiar with conventional cabinet makers rasps. What you might not know is that Oliver Carbide, the company that makes the notoriously popular Kutzall carving burrs, wheels, and sanding discs, also makes rasps. Like all Kutzall products, these rasps are made of tungsten-carbide.
Manufacturer: Oliver Carbide Products
Price: from $27.95US
Dimensions: 19/64″ x 13/16″ x 13″
Handle: 5″ rubber clad
Overall cutting surface: 8″ (6″ also available)
Body: Steel with tungsten carbide coating
Profile: Flat, Half Round, Warding
Finish: Coarse, Fine
Made in: USA
You probably know of tungsten-carbide from planer and jointer blades, router bits, and saw blade teeth. It’s one of the hardest, most durable, wear-resistant composite metals around. And, unlike tool steel, it will never rust.
There are three styles of Kutzall rasps – flat, half-round, and warding. Each is available in fine and coarse grades, and in both 6″ and 8″ lengths. I’ve been using the fine and coarse half-round rasps in my shop for several years and am exceptionally pleased with their performance.
You’ll notice in the photo above that Kutzall rasps have a flat end, rather than the more typical spear point that you’ll find on conventional rasps, like the Gramercy. The tang runs the full length of the rasp and is covered with a thick rubber handle. The handles are quite comfortable, even when used continuously for long periods of time, even if they aren’t as photogenic as wooden handles. Overall rasp length is about 13″, of which the handle makes up 5″. Kutzall rasps fall into the same weight class as conventional rasps.
The important distinction between conventional and Kutzall rasps are the teeth. Both rasps begin with steel bars. On conventional rasps, whether machine-cut or hand-cut, teeth are raised (by striking a punch) on the bars. The teeth can be in regular rows, as in the photo above, or staggered. The size and number of teeth determine the smoothness of the cut.
On Kutzall rasps steel balls are bonded to the bar, and then tungsten carbide conical teeth are bonded to the steel balls. Here as well, the size and number of teeth determine the smoothness of the cut.
You’re right in thinking that those conical teeth will abrade material differently than the spade shaped teeth on conventional rasps. These teeth cut noticeably quicker and leave a surface that is almost as smooth that produced by a conventional rasp.
While tungsten-carbide is exceptionally durable, I would expect that, over time, these conical teeth will loose some of their definition, becoming more blunt. The effect of this will likely mean that the rasps will cut somewhat slower, which would put it on par with the cutting speed of a conventional rasp.
As you can see in the photo above, there are significantly more teeth on a Kutzall rasp, and the teeth are much closer together than on the Gramercy.
The Gramercy rasp that I am most familiar with doesn’t load up much, on either soft or hard woods. I found that the Kutzall rasps load up a tad more. The top photo shows how much the Kutzall fine rasp loaded up after five minutes of shaping a stick of Ash. A couple of strokes with a file cleaner easily removes the debris.
The Gramercy smooth rasp (11 tpi) produces a slightly smoother finish than the Kutzall fine rasp but cuts a tad slower. The difference in finish is essentially negligible, as you still need to do a final smoothing with card scrapers or sandpaper.
The Kutzall coarse file cuts exceptionally quickly and would be my first choice when there is a lot of material that needs to be removed. A few strokes with the Kutzall fine rasp would reduce the amount of time need to achieve a final smooth surface.
Kutzall rasps might not have the prestige of hand-cut rasps, but at less than half the price, and considering their performance, they offer substantially better value. Unless you use the rasp day-in and day-out, they’ll last a lifetime. I found that the Kutzall rasps worked exceptionally well, whether cutting with or against the grain, in any direction. They’re ideal when you need to smooth tight curves, particularly on highly figured stock, and they leave a surface that doesn’t take a lot of time and effort to smooth with card scraper or sandpaper.
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