Alloy Artifacts

Sockets and Drive Tools

Plomb produced a full line of drive tools and sockets, with drive sizes including 1/4, 9/32, 3/8, 1/2, 3/4 and 1 inch. Corresponding sockets were available in 6-point, 12-point, and 8-point broachings, in shallow and deep formats, and for both regular and impact service.

Early Drive Tools

Based on catalog information and known examples, Plomb's production of standard square-drive sockets began in 1927 or 1928. Prior to this time, Plomb apparently experimented with some non-standard drive formats, including male-drive sockets in both hex and square formats. Most of these were discontinued once the standard square drive tools became available, but sockets in the largest drive size, the "Big Bertha" 7/8-drive tools, continued to be made with male-drive sockets until at least 1933.

Tools of this early vintage are extremely rare and generally poorly understood, due to a lack of catalog documentation and the scarcity of examples. However, we do have a few examples to present, and hope to acquire more in the future.

Early 9/16-Hex Drive Speeder

Fig. 89. Plomb 9/16 Hex Drive Speeder, with Insets for Marking Detail and Broaching, ca. 1924-1927.

Fig. 89 shows an extremely rare early Plomb 9/16 hex speeder socket wrench, which served both as a wrench and as the drive tool for a set of 9/16 male hex drive sockets. The speeder is marked "Plomb Tool Mfg. Co." near the socket end, as shown in the left inset.

The overall length is 17.6 inches, and the finish is black oxide.

The speeder wrench was acquired with three matching 9/16 male hex drive sockets, as shown in the next figure.

Early 9/16-Hex Drive Sockets

Fig. 90. Plomb 9/16 Male Hex Drive Sockets, with Insets for Marking Detail, ca. 1924-1927.

Fig. 90 shows the set of 9/16 male hex drive sockets acquired with the speeder, all marked "Plomb" with plumb-bob symbols at each end. (The hole in the marking for the middle socket is the back end of the friction ball recess.) The sizes are, from the left, 7/16, 1/2, and 5/8.

The 9/16 drive tang of each socket is equipped with a friction ball to secure the socket in the speeder wrench.

The three socket sizes together with the 9/16 speeder wrench covered the common hex sizes from 7/16 to 5/8, making this set convenient for many common service jobs.

1/2-Drive Tools

We'll begin the main presentation with the 1/2-drive tools and sockets, as this was the most frequently used drive size and examples are readily available. Plomb was producing tools in 1/2 (square) drive as early as 1927, although this first date is still somewhat open to question.

DTH 1/2-Drive Flex-Head Breaker Bar

Fig. 91. Plomb DTH 1/2-Drive Flex-Head Breaker Bar, with Insets for Detail, 1931.

Fig. 91 shows a rare early 1/2-drive Plomb DTH flex-head breaker bar, called a "hinge handle" in the catalogs. The tool is marked "Los Angeles" with the PLOMB (round-O) logo and a "1D" date code, plus the patent notice "Patent 1380643".

The overall length is 18.5 inches, and the finish is polished steel.

The date code indicates production in 1931, and the "DTH" model similarly indicates early production. This model of breaker bar would later be given model number 5468, as we'll see in a later figure.

This tool is covered under patent #1,380,643, issued in 1921 to S. Eagle.

5466 1/2-Drive Flex-Head Breaker Bar

Fig. 92. Plomb 5466 1/2-Drive Flex-Head Breaker Bar, with Inset Showing Logo, 1933.

Fig. 92 shows another rare early breaker, a 1/2-drive Plomb 5466 flex-head breaker bar marked with the PLOMB (round-O) logo and "Los Angeles", along with the "Patent 1380643" notation. The breaker bar is also marked with a "3B" date code for 1933.

The overall length is 9.4 inches, and the finish is polished steel.

The notice for the Eagle 1921 patent #1,380,643 was frequently marked on early Plomb breaker bars.

5467 1/2-Drive Flex-Head Breaker Bar

Fig. 93. Plomb 5467 1/2-Drive Flex-Head Breaker Bar, with Inset Showing Reverse, ca. 1945-1948.

In Fig. 93 we see a Plomb 5467 1/2-drive flex-head breaker bar or hinge handle, generally similar to the prior example but produced some years later.

The overall length is 16.0 inches.

Hinge handles were offered in three 1/2-drive models, 5466, 5467, and 5468, with nominal lengths 10, 15, and 18 inches respectively.

5468 1/2-Drive Flex-Head Breaker Bars

The next two figures complete the trio of 1/2-drive flex-head breaker bars offered by Plomb.

Fig. 94. Plomb 5468 1/2-Drive Flex-Head Breaker Bar, with Inset Showing Logo, ca. 1939-1945.

Fig. 94 shows an earlier 1/2-drive Plomb 5468 flex-head breaker bar, stamped "Made in U.S.A." with the PLVMB logo.

The overall length is 17.3 inches, and the finish is plain steel.

The round knurled handle is equipped with a hole for a cross-bar.

Fig. 95. Plomb 5468 1/2-Drive Flex-Head 'Pebbled' Breaker Bar, with Inset Showing Reverse, ca. 1945-1948.

Fig. 95 shows a later model 5468 breaker bar with a pebble-style background, marked "MFD. U.S.A." on the reverse.

The overall length is 19.0 inches, and the finish is chrome plating.

One interesting difference is that this later model is substantially longer than the example in the previous figure. A check with another Plomb collector confirms that this is not a fluke; apparently the breaker bars were made with some variation in length.

Mystery 1/2-Drive Flex-Head Breaker Bar

This next example is a reminder that even after you think you know something about Plomb, the next tool along may not fit any of your expectations.

Fig. 96. Plomb Mystery 1/2-Drive Flex-Head Breaker Bar, with Insets for Logo and End, 1938.

Fig. 96 shows a Plomb 1/2-drive flex-head breaker bar, clearly marked "U.S.A." and with a code "8A", apparently indicating manufacture in 1938. The finish is chrome plate and the overall length is 11.3 inches.

The breaker bar features a cross-bar hole with a detent ball, and in addition has a 1/2-drive broach in the end, as shown in the top inset. This latter feature allows the tool to act as an extension as well as a drive tool; this handy combination was often seen in the 1930s, but unfortunately has vanished from modern tools.

The above facts are clear enough, but now several problems emerge. The first is that there is no model number marked on the tool, which is unusual for Plomb.

The second oddity is that the "U.S.A." marking normally occurs with date codes for 1939 and later, but the present tool is marked for 1938. Possibly this tool was made very late in 1938, as the marking changes sometimes took several months to complete.

The final problem is that the features and dimensions of this tool don't match any of the known catalog models. The length of 11.3 inches makes it intermediate between the 5466 and 5467 models, and none of the catalog breaker bars were offered with end broaches. (Plomb did make a WF-series breaker bar with an end broach during the war, however.)

There may be reasonable explanations for the above oddities, but in summary this tool has to be regarded as a bit of a mystery, at least until further information is discovered.

5469 1/2-Drive Flex-Head Speeder

Our next figure shows a fine example of a less commonly seen drive tool, called a "speed hinge handle" in the Plomb catalogs, and combining the features of a flex-head breaker bar with a speeder. This tool offers great leverage to first break a nut loose, then with the head back in the straight position can be operated as a standard speeder.

Fig. 97. Plomb 5469 1/2-Drive Flex-Head Speeder, with Inset for Detail, 1934.

Fig. 97 shows a 1/2-drive Plomb 5469 flex-head speeder, marked "Los Angeles" with the PLVMB logo and a "4C" date code.

The overall length is 15.9 inches, and the finish is polished steel.

The handle is constructed of 9/16 diameter rod to provide the strength needed for a breaker bar.

5485 1/2-Drive Sliding Tee Breaker Bar

The previous several figures have shown flex-head breaker bars, so it's time to examine the other popular style, the sliding Tee handle.

Fig. 98. Plomb 5485 1/2-Drive Sliding Tee Breaker Bar, with Inset for Detail, 1936.

Fig. 98 shows a Plomb 5485 1/2-drive sliding Tee breaker bar, marked "Los Angeles" with the PLVMB logo. The overall length is 14.0 inches.

The date code is marked "6B", indicating production in 1936.

This tool is one of several purchased from the original owner, all of which were in remarkably good condition for 60 to 70 year old tools.

5486 1/2-Drive Ell-Handle Breaker Bar

Fig. 99. Plomb 5486 1/2-Drive Ell-Handle Breaker Bar, with Insets for Marking Detail, 1936.

Fig. 99 shows a 1/2-drive Plomb 5486 Ell-handle breaker bar, marked "Los Angeles" with the PLVMB logo and a "6D" date code.

The overall length is 14.0 inches. The finish is plain steel, with some pitting due to rust.

5480 1/2-Drive Speeder Handle

Fig. 100. Plomb 5480 1/2-Drive Speeder Handle with Inset, ca. 1943-1945.

Fig. 100 shows another common drive tool, the Plomb 5480 1/2-drive speeder handle. The overall length is 17.8 inches.

The finish on this tool appears to have originally been a thin cadmium plating, now worn off in many places. This suggests a likely manufacture date in the range 1943-1945.

5449 1/2-Drive Ratchets

The next figures show two generations of the model 5449 ratchet.

Fig. 101. Plomb 5449 1/2-Drive Ratchet, with Insets for Side View and Marking Detail, ca. 1939-1945.

Fig. 101 at the left shows a Plomb 5449 1/2-drive ratchet with a knurled handle, marked "Made in U.S.A." and with a "BB" code.

The overall length is 10.3 inches, and the finish is polished steel.

The ratchet mechanism for this model (and Plomb ratchets in general) uses two pawls with a lobed shifter to push aside the inactive pawl.

Fig. 102. Plomb 5449 1/2-Drive Ratchet, with Inset for Reverse Detail, ca. 1945-1948.

Fig. 102 at the left shows a later Plomb 5449 ratchet with a pebble-style handle, marked "Mfd. U.S.A." on the reverse.

The overall length is 10.2 inches, and the finish is chrome plating.

Plomb also offered a 1/2-drive model 5450 ratchet with a longer handle.

5460 1/2-Drive Extension

Fig. 103. Plomb 5460 1/2-Drive 3 Inch Extension, with Inset for Model, 1936.

Fig. 103 shows a Plomb 5460 1/2-drive extension, marked "Los Angeles" with the PLVMB logo. The overall length is 3.0 inches.

The date code is marked "6E" indicating production in 1936. The finish is polished steel.

5463 1/2-Drive Extension

Fig. 104 presents a comparison of two generations of the Plomb 5463 1/2-drive extension. The earlier example on the bottom is marked "Los Angeles" with the PLOMB (round "O") logo, and bears a date code of "2C" indicating production in 1932.

The later extension at the top is marked "Made in U.S.A." with the PLVMB logo; no date code is marked, but the chrome finish makes the production likely from 1945-1948. The overall lengths are 9.7 inches.

Fig. 104. Plomb 5463 1/2-Drive 10 Inch Extensions, with Inset for Detail, from Bottom: 1932, 1945-1948.

The earlier example has a polished but unplated finish, and the marks on the shaft indicate that it was ground and polished by hand. The later tool is finished in chrome plate with a polished drive end, and looks to have been made by automated production methods.

Another difference between the two examples is that the later extension has a cross-bar hole in the base, allowing it act as a T-handle. Cross-bar holes were added to the model 5463 extension in 1936; previously they had been available only with the longer 18- and 25-inch extensions.

The later extension shows the Plomb characteristic fluted base and stop-ring; this design persisted for many years after the Plomb era, and can be seen in the later sub-brands such as Fleet and Challenger. See for example the much later Vlchek and Challenger extensions.

Early DD16 1 Inch Socket

Plomb's earliest 1/2-drive sockets were given model numbers with a "DD" prefix, with sizes in 16ths instead of 32nds. These sockets were produced beginning in 1927 or 1928.

Fig. 105. Early Plomb DD16 1 Inch Socket, 1928.

Fig. 105 at the left shows a rare early DD-series socket, a 1/2-drive Plomb DD16 1 inch socket. The socket is marked "Los Angeles" with the PLOMB (round-O) logo, and has an "8B" date code for 1928.

The finish is plain steel.

Early 5428 7/8 Socket in Rope-Banded Style

The next figure shows an example of a socket with a rope-like knurled band, a decorative style used by Plomb in the late 1920s and early 1930s.

Fig. 106. Early Plomb 5428 7/8 Socket, with Insets for Broaching and Marking Detail, 1932.

Fig. 106 at the left shows a rare early socket in the "Rope Banded" style, a 1/2-drive Plomb 5428 7/8 socket marked "Los Angeles" with the PLOMB (round-O) logo. The date code is marked "2A" (though the "A" is hard to read), indicating production in 1932.

The finish is plain steel.

Note that the drive end of the socket has a retaining hole, a feature Plomb called "hole-tight" in their catalogs.

Based on information from other collectors, rope-banded sockets are known to have been made from at least 1929 through 1933. Interestingly though, this production overlaps with the production of non-banded sockets, raising the question as to why the different styles were being made.

Early 5430 15/16 Socket

Fig. 107. Early Plomb 5430 15/16 Socket, with Insets for Broaching and Marking Detail, 1932.

Fig. 107 at the left shows another early socket from 1932, a 1/2-drive Plomb 5430 15/16 socket, marked "Los Angeles" with the PLOMB (round-O) logo and a "2A" date code.

The finish is plain steel.

As with the previous example, the drive end of the socket has a "hole-tight" retaining hole.

Early 5344 11/16 Deep Socket

In addition to the standard sockets, Plomb was producing 1/2-drive deep sockets at least as early as 1930, as the next figure illustrates.

Fig. 108. Early Plomb 5344 11/16 Deep Socket, with Insets for Detail, 1930.

Fig. 108 at the left shows a rare early deep socket, a 1/2-drive Plomb 5344 11/16 deep socket marked "Los Angeles" with the PLOMB (round-O) logo. The date code is "0A", indicating production in 1930.

The finish is plain steel.

The drive end of the socket has smooth walls and no retaining hole, as this was apparently before Plomb started adding their "hole-tight" feature. The top inset shows the cold-broached construction.

In addition to being a rare item, this socket was a rare fortuitous find, as it was rescued from the 50 cent bargain bin of a used tool emporium.

Early 5348S 7/8 Special Thin Deep Socket

Fig. 109. Early Plomb 5348S 7/8 Special Thin Deep Socket, with Insets for Detail, 1937.

Fig. 109 shows a very rare 1/2-drive Plomb 5348S 7/8 deep socket with extra thin walls, stamped "LA" with the PLVMB logo, and with a "7B" date code for 1937. The socket is also stamped "No Guar.", as the thin walls made breakage too likely.

The finish is polished steel.

The drive end of the socket is equipped with a cross-bar hole, a standard convenience feature for sockets intended for spark-plug service.

5440-L 1/2-Drive 1-1/4 Semi-Deep Socket

Fig. 110. Plomb 5440-L 1/2-Drive 1-1/4 Semi-Deep Socket, with Inset for Broaching, ca. 1943-1945.

Fig. 110 at the left shows a very rare 1/2-drive Plomb 5440-L 1-1/4 semi-deep socket, marked "Made in U.S.A." with the PLVMB logo.

The finish is plain steel.

The socket height is 2.3 inches, substantially greater than the 1.7 inch height of a standard 5440 socket.

Currently no catalog reference for this socket has been found, suggesting that it might have been a special-order tool. The hot-broached construction and plain steel finish indicate a likely manufacturing date in the range 1943-1945.

5428-S 1/2-Drive 8-Point Socket

Plomb produced sockets with 8-point (double-square) broachings, although these are less frequently found than the 12-point sockets.

Fig. 111. Plomb 5428-S 1/2-Drive 7/8 8-Point Socket, with Inset for Broaching, ca. 1939-1945.

Fig. 111 shows a 1/2-drive Plomb 5428-S 7/8 double-square socket, marked "Made in U.S.A." with the PLVMB logo.

The finish is polished steel. This socket appears to be almost unused, with a thin coat of rust-proofing lacquer still present on the surface.

Proto 5424 1/2-Drive Socket with Plomb Tool Marking

Previous figures have shown some early Plomb sockets, and this next figure shows a very late Plomb-Proto dual-marked socket. Such dual markings are fairly common on other tools, but for some reason are quite rare on sockets.

Fig. 112. Proto 5424 1/2-Drive 3/4 Dual-Marked Socket, with Inset for Broaching, 1948.

Fig. 112 shows a very rare 1/2-drive Proto 5424 3/4 socket, marked "Plomb Tool Co." and "MFD USA". Note that all of the "O" letters are rendered with inverted triangles, a reminder of the PLVMB logo.

The finish is polished chrome plating.

6522 7/16 Specialty Socket

Fig. 113. Plomb 6522 1/2-Drive 7/16 Connecting Rod Socket, with Inset Showing Broaching, ca. 1939-1948.

Fig. 113 shows a 1/2-drive Plomb 6522 specialty socket for Cadillac connecting rod applications. The socket is basically a 1/2-drive 7/16 deep socket, but with an extra thin neck to work in the restricted space. The socket is marked "Made in U.S.A." and has a 6-point broaching.

The socket is finished in chrome plate.

3/8-Drive Tools

Plomb's 3/8-drive tools basically mirrored their 1/2-drive counterparts. Sockets and drive tools were both numbered in 52xx series.

5265 3/8-Drive Flex-Head Breaker Bars

The next figures show two generations of the 5265 flex-head breaker bar or hinge-handle.

Fig. 114. Plomb 5265 3/8-Drive "Los Angeles" Breaker Bar, with Inset for Detail, 1933.

In Fig. 114 we see a rare early example of a Plomb 3/8-drive tool, a model 5265 flex-head breaker bar with the PLOMB (round-O) logo. The markings are "Los Angeles" and "Patent No. 1380643", the same patent previously mentioned with the 5466 Breaker Bar.

The overall length is 7.4 inches.

The date code is marked "3B", indicating production in 1933. The finish is polished steel.

Fig. 115. Plomb 5265 3/8-Drive Pebbled Breaker Bar, with Inset for Reverse, 1945-1948.

Fig. 115 shows a much later example of the model 5265 breaker bar, this time in the pebble style and marked "Mfd. U.S.A." on the reverse.

The overall length is 7.8 inches, and the finish is chrome plating.

5285 3/8-Drive T-Slider Breaker Bar

Fig. 116. Plomb 5285 3/8-Drive T-Slider Breaker Bar, with Inset for Detail, 1939-1945.

Fig. 116 shows a Plomb 5285 3/8-drive T-slider breaker bar, marked "Made in U.S.A." with the PLVMB logo. The overall length is 7.1 inches.

The finish is a thin cadmium plating, now mostly worn off.

This tool shows a Down/Up pattern in the arrowheads flanking the PLVMB logo, a recently noted oddity.

5249 3/8-Drive Ratchets

The next figures show two generations of the Plomb 5249 ratchet.

Fig. 117. Plomb 5249 3/8-Drive Ratchet, with Inset for Reverse, 1939-1945.

Fig. 117 shows a 3/8-drive Plomb 5249 ratchet, marked "Made in U.S.A." with an "AC" code. The overall length is 7.1 inches.

The finish is polished steel.

The ratchet mechanism uses a 25-tooth gear with dual pawls, each with a single-tooth contact area. The shift lever operates a cam to alternately disengage one of the pawls.

Fig. 118. Plomb 5249 3/8-Drive Pebbled Ratchet, with Insets for Side View and Reverse Detail, 1945-1948.

Fig. 118 at the left shows a 3/8-drive Plomb 5249 ratchet in the pebbled style, marked "Mfd. U.S.A." on the reverse. The overall length is 7.0 inches.

The finish is chrome plating with a polished head, now worn away in some areas.

5249 (V239.17-1) Special-Order Ratchet

Plomb's standard tools were sometimes used as the starting point for various special-order tools, and this next figure shows an example of a 5249 ratchet modified for a special application.

Fig. 119. Plomb 5249 Special-Order Ratchet, with Insets for Side View and Reverse, ca. 1942-1945.

Fig. 119 shows a very rare and unusual Plomb special-order ratchet, made with a cut-out drive gear fitted with a pin. The top of the ratchet is marked as model 5249 with the PLVMB logo, and a faint "War Finish" stamping can be seen below the shifter. The reverse is stamped "Made in U.S.A." with a "BC" code, and a code "V239.17-1" is stamped just below the cover plate.

The overall length is 4.5 inches, and the finish is plain steel.

The application for this tool is currently not known. The ratchet appears to be designed to turn a shaft using the pin in the drive gear, but because the drive gear has been cut away, the gear will disengage from the pawl after a partial turn.

The "V239.17-1" code is likely a model number or specification for the tool and might help identify the original purpose. If any readers are familiar with this tool, please let us know via the "Contact Us" link on the home page.

5279 3/8-Drive 3/4 Universal Socket

Plomb produced universal (flex) sockets in 3/8- and 1/2-drive sizes, beginning at least by 1933 and possibly earlier. Universal sockets were offered only with 12-point broachings.

Fig. 120. Plomb 5279 3/8-Drive 3/4 Universal Socket, 1939.

Fig. 120 shows an example of a 3/8-drive universal socket, a model 5279 of size 3/4. The socket is marked "Los Angeles" with the PLVMB logo, and the date code is marked "9A", indicating production in 1939.

The socket construction is cold-broached; if you look closely at the photograph, you can see chatter marks on the broached surface. The finish is polished steel.

Universal sockets in 3/8-drive were offered in models 5274 (7/16), 5275 (1/2), 5276 (9/16), 5277 (5/8), 5278 (11/16), and 5279 (3/4).

5239 3/8-Drive Pan Screw Driver

The next figure shows a specialty driver tool designed for Chevrolet oil pan screws.

Fig. 120B. Plomb 5239 3/8-Drive Pan Screw Driver, with Inset for Top View.

Fig. 120B shows a rare 3/8-drive Plomb 5239 pan screw driver, stamped "Made in U.S.A." with the PLVMB logo.

The overall height is 1.9 inches with the sleeve extended and 1.6 inches compressed. The finish is chrome plating.

This socket driver was intended primarily for servicing the oil pan screws on certain Chevrolet models. The spring-loaded sleeve centers the driver bit on the screw and compresses as needed to engage the bit.

3/4-Drive Tools

Plomb introduced the 3/4 drive size in the late 1920s with a DDX socket series and a modest selection of drive tools. We're not sure of the exact date of the introduction, but the 3/4-drive sockets were definitely available by 1929, based on an example presented below.

Plomb's later 3/4-drive tools basically mirrored their 1/2-drive counterparts, with sockets in a 55xx series and drive tools in a 56xx series.

The 3/4-drive sockets presented one interesting difference in that two height (or depth) formats were produced, apparently from the very earliest production. The socket height depended on the opening size, so only one format was available for a particular size.

For example, sockets up to and including opening size 1-7/16 were proportioned as a standard socket, with larger sockets gradually increasing in height up to about 2.6 inches. But sizes 1-1/2 and larger suddenly jumped to a height of 3.5 inches, more like what other manufacturers offered as "deep" sockets.

5668 3/4-Drive Flex-Head Breaker Bar

Fig. 121. Plomb 5668 3/4-Drive Flex-Head Breaker Bar, with Insets for Construction and Marking Detail, 1938.

Fig. 121 shows a 3/4-drive Plomb 5668 flex-head breaker bar, stamped with the PLVMB logo and "L.A.", and with an "8C" date code for 1938.

The overall length is 23.2 inches. The finish is polished steel with some darkening due to rust.

The breaker bar is also stamped "Pat. No. 1380643", a reference to patent #1,380,643, issued in 1921 to S. Eagle. This patent has been noted previously on a Plomb DTH Breaker Bar from 1931, and on other figures as well.

5685 3/4-Drive T-Slider Breaker Bar

Fig. 122. Plomb 5685 3/4-Drive T-Slider Breaker Bar, with Inset for Logo, 1939.

Fig. 122 shows a Plomb 5685 3/4-drive T-slider breaker bar, stamped "Made in U.S.A." with the PLVMB logo and a "9B" date code for 1939.

The overall length is 18.5 inches, and the finish is polished stee

5661 3/4-Drive Extension

Fig. 123. Plomb 5661 3/4-Drive Extension, ca. 1939-1948.

Fig. 123 shows a 3/4-drive Plomb 5661 extension, stamped "Made in U.S.A." with the PLVMB logo.

The overall length is 8.0 inches, and the finish is chrome plating.

The drive head is equipped with a cross-bar hole for a 1/2 inch diameter bar, allowing (limited) use as a Tee-handle.

DDX25 Early 3/4-Drive 1-9/16 Socket

Fig. 124. Plomb DDX25 3/4-Drive 1-9/16 Socket, with Insets for Broaching and Marking Detail, 1929.

Fig. 124 shows a very rare early 3/4-drive Plomb DDX25 1-9/16 socket, stamped "Los Angeles" with the PLOMB (Round-O) logo and a "9A" date code for 1929.

The finish is polished steel, and the socket is decorated with five shallow grooves, a design feature used by Plomb for a number of years.

This socket is an early example of Plomb's "deep" format, with a height of 2.9 inches to allow clearance for long bolts. Later production increased the height of the deep sockets to 3.5 inches, but this example shows that the deep format had an early beginning.

The lower left inset shows the broached interior of the sockets. Chatter marks from the cold broaching operation are present on both the square drive opening as well as the service opening.

5534 3/4-Drive 1-1/16 Socket

Fig. 125A. Plomb 5534 3/4-Drive 1-1/16 Socket, with Inset for Broaching, 1943-1945.

Fig. 125A shows a 3/4-drive Plomb 5534 1-1/16 socket, marked "Made in U.S.A." with the PLVMB logo.

The finish is plain steel with a rough (unpolished) surface.

This socket is proportioned as a standard or "shallow" socket, with a height of 2.0 inches.

5542 3/4-Drive 1-5/16 Socket

Fig. 125B. Plomb 5542 3/4-Drive 1-5/16 Socket, with Inset for Broaching, 1939.

Fig. 125B shows a 3/4-drive Plomb 5534 1-1/16 socket, stamped with the PLVMB logo and "Made in U.S.A.", and with a "9B" date code for 1939.

The finish is polished steel.

This socket is proportioned as a standard or "shallow" socket, with a height of 2.5 inches.

5548 3/4-Drive 1-1/2 Deep Socket

The next several figures show examples of Plomb's "deep" format 3/4-drive sockets.

Fig. 126. Plomb 5548 3/4-Drive 1-1/2 Socket, with Inset for Broaching, 1943-1945.

In Fig. 126 we see a 3/4-drive Plomb 5548 1-1/2 deep socket, marked "Made in U.S.A." with the PLVMB logo.

The height is 3.5 inches, and the finish is plain steel with an unpolished surface.

This socket is an example of Plomb's "deep" format, with the extra height intended to provide clearance for long bolts.

5556 3/4-Drive 1-3/4 Deep Socket

Fig. 127A. Plomb 5556 3/4-Drive 1-3/4 Socket, with Inset for Broaching, 1943-1945.

Fig. 127A at the left shows a 3/4-drive Plomb 5556 1-3/4 deep socket, stamped "Made in U.S.A." with the PLVMB logo.

The height is 3.5 inches, and the finish is polished steel.

5558 3/4-Drive 1-13/16 Deep Socket

Fig. 127B. Plomb 5558 3/4-Drive 1-13/16 Socket, with Inset for Broaching, 1938.

Fig. 127B at the left shows a 3/4-drive Plomb 5558 1-13/16 deep socket, stamped "Los Angeles" with the PLVMB logo, and with an "8C" date code for 1938.

The height is 3.5 inches, and the finish is polished steel.

5572 3/4-Drive 2-1/4 Deep Socket with Cross-Bar Hole

Fig. 128. Plomb 5572 3/4-Drive 2-1/4 Socket, with Insets for Drive End and Broaching, 1943-1945.

Fig. 128 shows a 3/4-drive Plomb 5572 2-1/4 deep socket with a cross-bar hole, marked "Made in U.S.A." with the PLVMB logo.

The height is 3.8 inches, and the finish is cadmium plating.

7/8-Drive Tools

Prior to 1935 Plomb's largest socket tools were based on 7/8-inch male drive sockets. These tools were amusingly called the "Big Bertha" socket set, and although we don't have any examples to show, Fig. 129 below offers an illustration of the tools from an early catalog.

Catalog Illustration of Early 7/8 Male Drive "Big Bertha" Socket Set

Fig. 129. Catalog Illustration of Big Bertha Socket Set, 1930.

Fig. 129 at the left shows a catalog illustration of Plomb's "Big Bertha" 7/8-drive socket set from about 1930. (The humorous name "Big Bertha" used here originally referred to a large gun used by the German army in World War I, but later appears to have become part of the popular culture of the 1920s.)

The catalog listing describes the Zxx series of sockets with 7/8 square drive shanks, in sizes from 15/16 through 2 inches, together with the ZR14 ratchet, ZH breaker bar, and ZE extension.

The illustration was taken from an industrial supply catalog published around 1930, showing that Plomb tools were available through the industrial distributors of the time.

1 Inch Drive Tools

By 1935 the 7/8 male-drive sockets had been discontinued in favor of 1 inch drive sockets with a standard female drive connection. The sockets were also furnished with a cross-bar hole in the extended base, allowing the socket to be used as a sliding T-handle.

Plomb's initial selection of 1 inch drive tools included only a sliding T-handle and two extensions, with the extensions also equipped with a cross-bar hole. By 1940 a 1 inch drive ratchet was available, and the "Big Bertha" name returned again in the catalog description for the ratchet.

The sockets were available in sizes ranging from 1-5/8 to 3-1/2 inches, but with a number of gaps in the sequence, as shown in the table below. Socket model numbers began at 5752 for the 1-5/8 size and followed the pattern "57xx", where xx is the size in 32nds, with the two largest sockets overflowing to models 5800 and 5812 respectively.

The standard socket style included a cross-bar hole in the elongated base, allowing for use as a T-handle with the model 5885 bar. Sockets were available only in a 12-point broaching.

The table below summarizes the 1 inch drive tools listed in the Plomb catalogs, and in addition shows some of the known "Special Order" tools.

5849 "Big Bertha" 1 Inch Drive Ratchet

The next selection demonstrates that this gallery is more impressed by size than beauty. Fig. 130 shows a Plomb 5849 1 inch drive ratchet, affectionately termed "Big Bertha" by the catalog, and definitely well-endowed in the size department. (And maybe a bit of beauty if you're a diesel mechanic.) The ratchet has a knurled handle and an overall length of 26 inches.

Fig. 130. Plomb 5849 1 Inch Drive "Big Bertha" Ratchet, with Insets for Reverse Detail, ca. 1939-1945.

The finish is cadmium plating.

The ratchet has a 24-tooth drive gear, and the shift mechanism uses dual pawls with a lobed cam shifter. (This is the standard mechanism used by Plomb reversible ratchets.) The pawl springs are soft and provide very low back-drag for such a large ratchet.

Plomb also offered a very similar model 5848 ratchet with a female drive gear, for use with a drive plug.

5861-S 1 Inch Drive 8 Inch Extension

Fig. 131. Plomb 5861-S 1 Inch Drive Extension, ca. 1939-1945.

Fig. 131 shows a 1 inch drive Plomb 5861-S 8 inch extension, marked "Made in U.S.A." with the PLVMB logo.

The overall length is 8.2 inches, and the finish is cadmium plating.

One detail to note is that the model number of this tool has an "S" suffix, which generally indicates a special order or changed specification. In this case the apparent change was to omit the cross-bar hole in the drive end; Plomb's 1 inch drive extensions and sockets usually include a cross-bar hole, but apparently it wasn't needed for this application.

Several of the sockets purchased with this extension also had 58xx-S model numbers; some of these will be shown once the photographs have been prepared.

5863-S 1 Inch Drive 15 Inch Extension

Fig. 132. Plomb 5863-S 1 Inch Drive 15 Inch Extension, witn Inset for Marking Detail, ca. 1939-1945.

Fig. 132 shows a 1 inch drive Plomb 5863-S 15 inch extension, marked "Made in U.S.A." and with the PLVMB logo.

The overall length is 15.4 inches, and the finish is cadmium plating.

The model number for this tool has unfortunately been defaced by the use of a pipe wrench on the extension. However, based on its size and the example in the previous figure, acquired in the same lot of tools, it's likely that this would have been marked as model 5863-S. (The numbers and suffix are partially present in the detail inset.)

As with the previous figure, the normal cross-bar hole has been omitted from this particular tool. In addition, the length is somewhat shorter than the standard model 5863 extension, which has a nominal length of 17 inches.

5752 1 Inch Drive 1-5/8 Socket

Fig. 133. Plomb 5752 1 Inch Drive 1-5/8 Socket, with Inset for Broaching, ca. 1945-1948.

Our first example of the 1-inch drive sockets (and the smallest of the standard sizes) is shown in Fig. 133, a model 5752 1-5/8 socket marked "Made in U.S.A." with the PLVMB logo.

This socket was constructed with a hot-broaching process and has a hard (chrome) plated finish, placing the estimated manufacturing date in the range 1945-1948.

These sockets were provided with both the square drive and with a cross-bar hole, as in some cases the cross-bar might be more convenient to use. A model 5884 cross-bar was available for this purpose.

5754-S 1 Inch Drive 1-11/16 Sockets

The next two figures show examples of special-order 1 inch drive sockets, but with slightly different styles explained in the text below.

Fig. 134. Plomb 5754-S 1 Inch Drive 1-11/16 Socket, with Inset for Broaching, ca. 1939-1942.

Fig. 134 at the left shows a 1 inch drive Plomb 5754-S 1-11/16 socket, marked "Made in U.S.A." with the PLVMB logo. The finish is cadmium plating, and the cold-broached construction suggests a manufacturing date before 1943.

Readers familiar with Plomb's socket models will have already noticed the unusual configuration of this socket: the design is that of a 3/4-drive socket, with a cylindrical body, five grooves, and no cross-bar hole. The model number offers an explanation, with the "S" suffix indicating that this was a special-order item.

Apparently the customer (possibly a military contract) needed this size in 1 inch drive, but the 1-11/16 size wasn't available as a standard model. Plomb obliged by taking a model 5554 socket and broaching it for 1 inch drive, and then marked it as a special order part. (Presumably the cross-bar hole wasn't needed for this application.)

Fig. 135. Plomb 5754-S 1 Inch Drive 1-11/16 Socket, with Inset for Broaching, ca. 1939-1942.

Fig. 135 at the left shows another example of the Plomb 5754-S socket, marked "Made in U.S.A." with the PLVMB logo. The finish is cadmium plating, and the cold-broached construction suggests a manufacturing date before 1943.

This socket has a reduced base like the standard 1 inch drive sockets, but without a cross-bar hole. The model number has an "S" suffix to indicate that this was a special-order item.

5764 1 Inch Drive 2 Inch Sockets

The next figures show two variations of the Plomb 5764 socket.

Fig. 136. Plomb 5764 1 Inch Drive 2 Inch Socket, with Inset for Broaching, ca. 1939-1942.

Fig. 136 shows a 1-inch drive Plomb 5764 2 inch socket in the standard cross-bar style, marked "Made in U.S.A." with the PLVMB logo and an "AC" code.

The finish is plain steel.

The inset shows the cold-broached construction used by Plomb up until about 1943.

Fig. 137. Plomb 5764-N 1 Inch Drive 2 Inch Socket, with Inset for Broaching, ca. 1939-1942.

Another special-order variation occasionally seen in the 1 inch drive sockets is the use of a solid base, without the standard cross-bar hole. These sockets were typically given an "N" suffix to the model number, perhaps for "No Cross-Bar".

An example of a solid-base socket is shown in Fig. 137 at the left, a 1-inch drive Plomb 5764-N 2 inch socket without a cross-bar hole, marked "Made in U.S.A." with the PLVMB logo.

The finish is cadmium plating.

The inset shows the cold-broached construction used prior to 1943. Note that the socket does include a hole in the drive end (called a "Hole-Tite" hole in the catalogs) to help secure the socket.

5776 1 Inch Drive 2-3/8 Socket

Fig. 138. Plomb 5776 1 Inch Drive 2-3/8 Socket, with Inset for Broaching, ca. 1943-1945.

Fig. 138 shows a 1-inch drive Plomb 5776 2-3/8 socket in the standard cross-bar style, marked "Made in U.S.A." with the PLVMB logo.

The finish is cadmium plating.

The inset shows the hot-broached construction used by Plomb in 1943 and later. The hot-broached construction and cadmium finish suggest a manufacturing date in the range 1943-1945.

5780 1 Inch Drive 2-1/2 Socket

Fig. 139. Plomb 5780 1 Inch Drive 2-1/2 Socket, with Inset for Broaching, 1941.

Fig. 139 shows a 1-inch drive Plomb model 5780 2-1/2 socket in the standard cross-bar style, marked "Made in U.S.A." with the PLVMB logo and a "1C" date code.

The socket is finished with cadmium plating.

The inset shows the construction details; as expected for this earlier socket, the construction is cold-broached with remnants of the chips visible.

5788 1 Inch Drive 2-3/4 Socket

The next figure will be the final example for this section, and also happens to be (currently) the largest Plomb socket in our collection.

Fig. 140. Plomb 5788 1 Inch Drive 2-3/4 Socket, with Inset for Broaching, ca. 1943-1945.

Fig. 140 shows a 1-inch drive Plomb 5788 2-3/4 socket in the standard cross-bar style, marked "Made in U.S.A." with the PLVMB logo.

The socket has been painted at some point, but the original finish appears to have been either plain steel or cadmium plating.

The inset shows the hot-broached construction used in 1943 and later.

Other Drive Sizes

Plomb also produced tools in 1/4-drive and 9/32-drive, and we'll show a few examples of these in this section.

4749 1/4-Drive Ratchet

Fig. 141. Plomb 4749 1/4-drive Ratchet, with Insets for Side View and Marking DDetail, ca. 1945-1948.

At the opposite extreme of size from "Big Bertha", in Fig. 141 we see a Plomb 4749 1/4-drive ratchet in the pebble style, marked PLVMB with "Mfd. U.S.A." on the reverse.

The overall length is 5.1 inches, and the finish is chrome plating with polished faces.

4769 1/4-Drive Handle

Fig. 142. Plomb 4769 1/4-drive Handle, with Inset for End Broaching, ca. 1939-1948.

Fig. 142 shows a Plomb 4769 1/4-drive handle, marked "Made in U.S.A." with the PLVMB logo.

The overall length is 5.1 inches, and the finish is chrome plating.

The inset shows the 1/4-drive end broaching, allowing the handle to be used as an extension as well.

4785 1/4-drive T-Slider Breaker Bar

Fig. 143. Plomb 4785 1/4-drive T-Slider Breaker Bar, with Inset for Detail, ca. 1939-1945.

Fig. 143 shows a Plomb 4785 1/4-drive T-slider breaker bar, marked "Made in U.S.A." with an "F" code.

The overall length is 4.5 inches.

This tool shows a Down/Up pattern in the arrowheads flanking the PLVMB logo, a recently noted oddity.

4885 9/32-drive T-Slider Breaker Bar

Fig. 144. Plomb 4885 9/32-drive T-Slider Breaker Bar, ca. 1939-1945.

Fig. 144 shows the very similar 9/32-drive Plomb 4885 T-slider Breaker Bar, marked "Made in U.S.A." with an "F" code.

The overall length is 4.1 inches, and the finish is cadmium plating.

As with the previous example, this tool shows a Down/Up pattern in the arrowheads flanking the PLVMB logo.