Sew-It-Yourself Home Accessories. Scott Wynn
OF THE HORNED PLANE
Horned planes commonly come with 45° or 50° blade angles. I believe they were also made with 43° and 47.5° blade angles. Prep planes such as scrub planes sometimes have a 40° pitch; some finish planes have a pitch above 50°. A toothing plane is made with a 70° pitch. Check with the distributor if you are looking at new planes, or take a protractor to the flea market.
On premium models, the mouth opening adjusts with a movable mouthpiece (the reform plane). Chipbreakers are substantial and well-made, though some may require some refinement to function with a finely set mouth.
Primus planes use a traditional approach to bedding the blade by having it contact the bed at just its bottom and top. To do it, they have installed two metal buttons at the top of the blade bed to suspend the blade so it contacts the bed only at these points and at the bottom. This guarantees the blade is supported at the heel of the blade bevel, the most critical area for eliminating chatter. Though the blade and chipbreaker assembly bridges this distance, this assembly, further dampened by the tension rod which holds this assembly and is part of the adjustment system, is thick enough that the blade does not chatter.
The blade placement is a little more central than Bailey-style planes and most traditional wood planes, the blade edge being back from the leading edge of the plane about 40% of the length of the sole. This slightly more central position makes it a little easier to begin and complete a planing stroke.
The horn is available in both right- and left-handed versions.
AND A WORD ABOUT CHINESE-STYLE PLANES...
I think the Chinese-style planes can be useful to the Western woodworker. But since they are functionally exactly like western planes, the real advantage is being able to find planes with 60° and 65° blade angles already made. I wouldn’t bother buying one that has less than a 60° blade angle as there is (currently) a greater variety of quality planes and parts in the Western style in the lower angles. If you can source Chinese-style planes that have the high blade pitch, these planes can be really handy, if not indispensable, when working tropical hardwoods, many Australian hardwoods, and the harder Northern hardwoods. Conversely, if you never, or only rarely, use these woods, you will probably be able to get by without them (though my 60° Chinese jack works great on oak). The planes, with the correct pitch, work exceptionally well, and the ergonomics are easy for the Westerner to adapt to. But, if you are not comfortable with the Chinese-style form, you can always fabricate planes to your needs that have similar tactical specifications.
The planes used by Chinese cabinetmakers and furniture makers are functionally very similar to early European wood block planes (Figure 1-13). However, there are differences, and both these and the similarities are interesting to note. The blade-wedging techniques for the two is exactly the same: a wooden wedge holds the blade, itself held in place in a wedge-shaped slot cut in either side of the blade opening in the body. The same methods control tearout: the setup of the chipbreaker, and mouth opening; and the primary means, the blade angle. I think this is largely a result of having to plane the hard tropical woods traditionally used—a high-angle scraping cut seems to be more reliable. The smoothing plane has a blade angle of 65°+, no chipbreaker (which would seem unnecessary at this angle anyway), and a mouth opening of only several thousandths of an inch—barely enough to see light through when the blade is set. Often a brass piece is dovetailed into the throat to control wear (Figure 1-14).
Figure 1-14. The Sole of a Chinese-Style Plane You can see the brass mouthpiece dovetailed into the sole that is used to form a tight mouth and reduce wear.
The plane is pushed using a slightly oval-shaped handle that is inserted through a hole in the plane body behind the blade (though there are some variations of this from region to region, a fixed, oxbow-shaped handle being the most common). The palms of the hands straddle the plane and the handle. The fingers are on top of the plane in front of the blade and the thumbs are behind the blade. This is a comfortable position, allowing good body mechanics when planning. I am not used to it, however, and often use the plane without the cross handle. The handle itself is friction-fit and removes for storage or transport, or to accommodate the recalcitrant Westerner like myself who prefers not to use it.
The traditional blade is often laminated and parallel rather than tapered, but I would hesitate to say that this is always the case, as modern manufactured versions often use high-speed steel. The smoothing plane I bought, rather than having a laminated blade, had a piece of steel about an inch long braised onto the end of a longer, softer piece that forms the main body of the blade and projects from the plane. This piece of edge steel is extremely hard, and appears to be high in alloys, as it does not sharpen easily. I have never seen a blade constructed in this manner; I bought an extra one when I had the chance (Figure 1-15).
ANATOMY OF A CHINESE PLANE
It was not long ago that even seeing, let along buying, a Chinese plane was a rare thing. Now, not only is the classic style used throughout China and Southeast Asia available, but the market includes high-end Australian-made versions, as well as a number of regional styles.
The classic style of cabinetmaker’s plane is typically used to plane tropical hardwoods and so has a high blade angle. A set of prep, true, and finish planes would have angles of 55°, 60°, and 65° respectively. Because of the high-pitch angles, the plane usually relies on a tight mouth opening for controlling tearout, though sometimes a token chipbreaker would be supplied. The mouth opening usually is faced with a brass piece to reduce wear.
Some of the regional models have the cross handle let into the top and screwed to the body and may have an oxbow shape, rather than having a hole in through the body for the handle, a minor difference. Another regional difference, including planes from Taiwan, is a lower, wider proportion, reminiscent of Japanese planes, but with sweeping ergonomic curves to the body. The blade assemblies on many of these look like Japanese-blade assemblies, as well, with a wedge-shaped metal chipbreaker under a metal cross pin. However, the chipbreaker in these planes really does wedge the blade in place, as the blade itself is not wedged into the body the way the Japanese plane blade is. I have not worked with these, so I do not know if the result is a compromise in the ability to adjust the position of the chipbreaker or in the effectiveness of the wedge to hold the blade in position. If this design is successful at both of these (I’m not sure if this is a traditional design or a new hybrid), then it is a stroke of genius. One of the advantages of the Japanese plane is the ability to easily adjust the chipbreaker back and forth for different types of cuts. This can be done because the blade is wedged independently of the chipbreaker. In this Chinese plane, the blade adjustment is dependent on the chipbreaker’s position, and adjusting the chipbreaker too far one way may affect whether the blade will hold its position.
In the classic Chinese-style plane, the blade edge is positioned very near the center of the length of the sole, making entering and exiting the stroke about as balanced as it can be.
The main reason I use Chinese-style planes is their high blade angle and the effectiveness of that angle on tropical hardwoods. The central placement of the cutting edge is an added bonus. Many of the regional styles of Chinese planes are being sold with 45° blade angles and an alloy-steel blade cut from stock. As such, they have no real advantage over most other planes, other than perhaps price, and preferable ergonomics.
Figure 1-15. The blade on this Chinese plane has a hard piece of edge steel, about an inch long, brazed to a longer piece of soft steel to form the blade.
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