Sargent produced three of these planes, the No.2204, known as the All-Steel Block Plane (Pocket Plane), the No.4206, and the No.5206, both low-angle block planes. Their objective was to create a light, strong, durable and inexpensive plane – with the frame, the frog, and the clamp for the cutter constructed of sheet metal.
The No.2204 first appeared in 1913, and was manufactured for 30 years. It was essentially a palm-plane, with the heel of the plane sporting a pressed-metal heel which could be used to rest your palm on. The rest of the plane showed a simple construction. This block plane was unusual in that the blade was bevel-down due to the high bedding angle of 45º. It was constructed of four pressed steel components (sans blade): The body, the frog, the heel, and the lever cap. The frog and heel were spot-welded onto the body. The only adjustment mechanism on the plane was a blade depth adjustment using a crude thumbwheel engaging a slot in the top of the blade.
The No.5206 appeared in 1913 and was manufactured until 1947. It was composed of three pressed steel components (sans blade): the body, the frog, and the lever cap. The frog was spot-welded to the body, and contained a section which allowed the depth-adjustment screw to be anchored. the large mushroom-like cap on said screw is suppose to provide palm support. The “Hand-y” on either side of the plane is a hole cut into the wall, rather than a depression – largely due to the use of thinner pressed steel. There is no lateral adjustment or throat adjustment mechanisms.
There are many variants of this particular model. Some models, likely those made during WW2 had a black anodized finish. My collection includes three variants of the No.5206.
One way of distinguishing them is the placement of the forward finger knob. For the years 1913-1915, this knob was directly attached to the toe of the plane forward of the mouth. Variants manufactured from 1916 onwards had the knob attached to the lever cap (as shown above). There were also changes in the finish used on the planes: nickel plating (1913-1941), cadmium plating (1942-1947), and black anodized (1943-1946).
Another way of telling them apart is by viewing the trademarks on the cutters. From inspection it is clear that the first one is from the period 1919-1942, considered to be a Type 4 Sargent, whereas the remaining two are Type 5 Sargent’s, manufactured from 1942-1947.
The variants in the No.5206 show an evolution in small changes in the design, from when they were introduced in 1913 to their withdrawal in 1949. One of the more notable changes is that the earlier depth adjustment mechanisms used grooves cut in the backs of the blades to fit the collar. The latter variant has through slots, which were likely a cost-saving measure (these could be stamped versus grinding).
The second notable difference is the method used to join the “frog” to the body of the plane. In the earlier models it does not appear as if the tail of the frog is joined on the base of the body, however the latter model seems to be spot-welded to the body.
The method of holding down the lever cap evolved from a fixed pin, to a round-headed machine screw, to a machine screw with a “cheese” head.
Finally, the refinement of the knurled head on the machine screw responsible for applying pressure to the lever cap – the later variant has a much finer diamond-textured knurl.
The No.4206 was only manufactured for a short period, 1913-1918, and as such is quite rare. In many ways it is the same plane as the No.5206. It exists in both the variants where the finger knob is attached to the body (1913-1915), and attached to the lever cap (1916-1918).
The plane uses a fixed cross-pin to position the lever cap, instead of a machine screw. The machine screw responsible for applying pressure to the lever cap has a straight pattern, as opposed to the diamond pattern seen in later planes. The lever cap itself also has has a different shape, likely to maintain its shape with the forces applied by the cross-pin holding it in place.
The slot in the blade to fit the depth adjustment mechanism is peanut-shaped, more akin to what was found in later versions of the still block planes from Sargent. This version of the plane has the finger knob attached to the body.
The frog of the No.4206 has a shortened tail, which does not touch the sole of the plane.