The Owatonna Tool Company (OTC)

Table of Contents

Introduction

The Owatonna Tool Company is best known for its gear pullers and related tools.

Company History

The Owatonna Tool Company (OTC) was founded in 1925 by Reuben A. Kaplan, an engineer and inventor who had previously worked for Truth Tool. The company took its name from its location in Owatonna, Minnesota.

The founding date is based on a trademark application for "OTC" in stylized text, which listed September 1, 1925 as the first use date. In addition, by mid 1925 the company had begun placing classified advertisements for tool salesmen in the Chicago Tribune and possibly other newspapers.

Fig. 0A. 1925 Classified Ad for Owatonna Tool Company.

The scan in Fig. 0A shows a classified ad for a tool salesman placed by the Owatonna Tool Company, as published on page 76 of the July 12, 1925 edition of the Chicago Tribune.

In 1926 the company was incorporated by R.A. Kaplan, G.J. Kaplan, and James M. Peterson, as noted in the trade press.

Fig. 0B. 1926 Notice of Incorporation for Owatonna Tool Company.

The scan in Fig. 0B shows a notice of the incorporation of Owatonna Tool Company, as published on page 7 of the September 22, 1926 issue of Automotive News.

The text notes that the company was incorporated with $50,000 capital with the intent to manufacture tools and equipment for the garage business.

In 1927 the company filed an application for an important patent followed shortly by a trademark application for "OTC" in stylized text.

The Gear Puller Patent

Among the company's most successful early products were gear pullers based on patent 1,709,913, filed by Reuben Kaplan on July 15, 1927 and issued in 1929. The design of these pullers was brilliant in its simplicity, with the jaws connected to the yoke by a link so that the upper part of the jaw was braced against the yoke. This arrangement provided a gripping force proportional to the pulling force, ensuring that the jaw could not slip from the work piece.

The First Catalog

In 1975 the company reprinted its first catalog to celebrate its 50th anniversary, and with "1925" and "1975" prominently displayed on the front cover, it is natural to assume that the original catalog was published in 1925. (The cover actually states that it is a reprint of the OTC 1925 catalog.)

However, after a careful review of the contents, we now believe that the catalog was originally published in the latter part of 1927, not 1925. The key to our surprising finding is that the gear pullers are described as patented, and even if we allow "patented" to mean patent pending, this would place the catalog sometime after the July 15, 1927 patent filing date. The illustrations for the gear pullers closely resemble the illustrations for patent 1,709,913, so there is no ambiguity in the patent reference.

Additional evidence to support the later publication date can be found in the foreword to the catalog. The second sentence of the first paragraph states that "The company has achieved a steady growth and wide experience and has made some of the most successful tools ever offered ...", which is not a claim that a company could make just after being organized.

Further evidence is provided by the last sentence of the foreword, which states "The OTC trade mark insures THE UTMOST in tools." The reference to the OTC trademark suggests that the catalog was published after the August 15, 1927 trademark application.

Finally, the development of the new gear pullers in 1927 would have provided a rationale for the company to publish its first catalog.

San Francisco Branch Office

Fig. 1. 1929 Notice for Owatonna Tool Company. [External Link]

By 1929 the company had opened a branch office in San Francisco.

Fig. 1 shows a notice of the opening of the San Francisco branch, as published on page 33 of the June, 1929 issue of Motor West.

Sockets and Drive Tools

The 1929 OTC catalog introduced a line of sockets and drive tools in 3/8 and 1/2-drive, with chrome vanadium steel used for both sockets and tools.

Contract Production by Herbrand

By the mid 1930s OTC was using Herbrand as a supplier of wrenches, including combination, obstruction, and ignition styles. The Herbrand wrenches can be recognized in the catalog illustrations by their distinctive design.

Bearing Pullers and Push-Pullers

By 1936 OTC had developed a specialized bearing cup puller and an early version of a tool that could be set up to either push or pull, initially called a multi-purpose puller but later termed the "push-puller". These tools were covered by patents 2,052,304 and 2,288,906.

The push-puller operated on a different principle than conventional pulling tools. Although it resembled a yoke with arms and a central pressure screw, the arms of the push-puller could be rigidly bolted to the yoke to form compression struts, and the central screw then operated in tension as it extracted the work piece or a separate puller attachment.

Since the pressure screw was sometimes attached to the work piece, the hole in the yoke was not tapped and the pressure screw was moved by a nut on either side of the yoke. For work pieces with tapped holes available for pulling, the push-puller could also be operated as a conventional puller using long bolts as the pulling arms.

By 1940 the company had coined the term "Grip-O-Matic" for its gear puller line and later registered the term as a trademark.

Later Events

In 1985 OTC was acquired by the Sealed Power Corporation, a maker of piston rings and other OEM parts. Sealed Power later changed its name to the SPX Corporation. After the acquisition OTC operated as a division of SPX.

In 2012 SPX sold their Service Solutions business (including OTC) to Robert Bosch Gmbh.

Continuing Operations

OTC continues in operation as a division of Bosch Automotive Service Solutions, and additional information can be found at the OTC Tools [External Link] website.

Patents

Trademarks

In 1927 OTC filed a trademark application for the "OTC" logo, a design with the central "T" rising above and partially covering the "O" and "C". The application listed the first use date as September 1, 1925, and the trademark was issued as #237,653 on January 17, 1928. Reuben A. Kaplan was listed as president of the company.

The "Grip-O-Matic" and "Push-Puller" trademarks were registered with the first use in 1940.

Tool Identification

OTC tools were typically marked with the "OTC" logo, first used in 1925 and registered as trademark #237,653 in 1928.

Later tools may be marked with the OTC "Shield" logo, first used in 1944 and issued as trademark #788,115 in 1965.

OTC Logo

Fig. 2. OTC Logo from Trademark #237,653.

The scan in Fig. 2 shows the OTC logo as presented for trademark #237,653.

OTC-Shield Logo

Fig. 3. OTC-Shield Logo from Trademark #788,115.

The scan in Fig. 3 shows the OTC-Shield logo as presented for trademark #788,115.

References and Resources

Photographs and observations of particular tools are based on items in the Alloy Artifacts collection.

Catalog Coverage

Product information was obtained from a number of OTC catalogs, as summarized in the table below.

Many of the OTC catalogs are undated but can be placed in sequence by the assigned catalog number, which then allows an estimate of the publication date.

Gear Pullers

OTC initially offered its gear pullers in a two-jaw style in three sizes, which were given model numbers 1, 2 and 3.

By around 1936 the model numbers had changed to 1001 through 1003, and the selection expanded with additional sizes in later years.

By 1940 the company had started using the term "Gripomatic" (later written as "Grip-O-Matic") for its gear pullers. In addition, gear pullers with a three-jaw yoke were being offered in models 1011, 1012, and 1013, which corresponded in size with models 1001, 1002, and 1003.

No. 1000 "Grip-O-Matic" Two-Arm Gear Puller

Fig. 4. OTC No. 1000 Gear Puller.

Fig. 4 shows the smallest of the many OTC "Grip-O-Matic" puller models, the OTC No. 1000 gear puller.

The pressure screw is 4.0 inches long, the jaws is 2.7 inches long, and the yoke is 2.7 inches wide. The finish is plain steel for the yoke and pressure screw, and chrome plating for the jaws.

The "Grip-O-Matic" puller design is described by patent #1,709,913, filed by R.A. Kaplan in 1927 and issued in 1929.

No. 1001 "Grip-O-Matic" Two-Arm Reversible Gear Pullers

The next figures show two more examples of the OTC "Grip-O-Matic" line, both No. 1001 two-arm gear pullers, but with some differences in the construction.

Fig. 5. OTC Early No. 1001 Two-Arm Reversible Gear Puller.

Fig. 5 shows an early example of the OTC No. 1001 two-arm reversible gear puller, stamped "OTC Owatonna, Minn." and "Pat. 1709913" on one connecting plate with the model number on the opposite plate.

The pressure screw for this early model is 7.1 inches long and has a 1/2-20 diameter and thread pitch. The yoke is 3.0 inches wide, and the reversible jaws are 4.8 inches long. The finish is cadmium plating.

The "Grip-O-Matic" puller design is described by patent #1,709,913, filed by R.A. Kaplan in 1927 and issued in 1929.

Fig. 6. OTC No. 1001 Two-Arm Reversible Gear Puller.

Fig. 6 shows a somewhat later example of the OTC No. 1001 puller, stamped "OTC Owatonna, Minn." and "Pat. 1709913" on the connecting plate, with the model number stamped on the opposite plate.

The pressure screw for this puller is shorter at just 6.0 inches long, and the diameter has been increased to 9/16-20 diameter and thread pitch.

The yoke is 3.0 inches wide, and the reversible jaws are 4.8 inches long.

The finish is cadmium plating.

No. 1002 "Grip-O-Matic" Two-Arm Reversible Gear Puller

Fig. 7. OTC No. 1002 Two-Arm Reversible Gear Puller, with Inset for Marking Detail.

Fig. 7 shows a larger example of the Grip-O-Matic series, an OTC No. 1002 two-arm reversible gear puller, stamped "Owatonna Tool Co. Owatonna, Minn." and "Made in U.S.A." on the connecting plate.

The pressure screw is 8.9 inches long with an 11/16-18 diameter and thread pitch.

The yoke is 4.3 inches wide, and the reversible jaws are 8.6 inches long.

The finish is chrome plating.

The "Grip-O-Matic" puller design is described by patent #1,709,913, filed by R.A. Kaplan in 1927 and issued in 1929.

No. 927 "Push-Puller" Yoke

Fig. 8. OTC No. 927 Push-Puller Yoke, with Inset for Top View.

Fig. 8 shows an OTC No. 927 push-puller yoke, stamped with the OTC logo and "Owatonna Tool Co." above "Owatonna, Minn." on the side.

The inset shows a top view of the yoke, illustrating the two slots and the center hole.

The yoke is 8.2 inches long, 1.4 inches high and 1.4 inches wide. The slots are 0.5 inches wide, and the hole for the pressure screw has a 13/16 diameter.

The finish is cadmium plating.

The "Push-Puller" design is described by patent 2,288,906, filed by R.A. Kaplan in 1938 and issued in 1942.

The center hole is not tapped, as the pressure screw may be attached to the work piece and must be moved by a nut.

No. 518 Flange-Type Puller

Fig. 9. OTC No. 518 Flange-Type Puller, with Inset for Marking Detail, ca. 1970s.

Fig. 9 shows an OTC No. 518 flange-type puller, stamped with the OTC logo and "Owatonna Tool Co." followed by the model number.

The center hole has been tapped for use with a 5/8-18 pressure screw.

The puller body is 5.9 inches long by 5.3 inches wide by 1.0 inches high.

The finish is cadmium plating.

This puller is designed for removing parts such as pulleys or steering wheels that have been equipped with tapped holes. With slots along the center and in the side arms, the puller can accomodate work pieces with two or three tapped holes in a range of sizes.

The No. 518 puller was listed in catalog AM-75 from the mid 1970s.

Wrenches

OTC began as a maker of automotive specialty tools and did not rush to provide the standard styles of wrenches widely available from other manufacturers. By 1929 the company was offering box-end wrenches (still relatively new at that time) and tappet wrenches.

Box-End Wrenches

By 1929 OTC was offering 12-point box-end wrenches in a number of sizes, and in standard, single-ended, and short styles.

Fig. 10. 1929 Catalog Listing for OTC Box-End Wrenches.

The scan in Fig. 10 shows the listing for box wrenches, as published on page 9 of the 1929 catalog 20-A.

The text notes that the wrenches were forged from chrome-vanadium steel.

A close look at the illustration shows the distinctive tapered box ends, a style that appears to have been first offered by P & C. P & C was one of the first companies to offer box-end wrenches forged from chrome-vanadium steel, and by 1929 it had begun offering twelve-point offset box wrenches.

We think it's likely that OTC sourced these wrenches from P & C.

Early [3034] 15/16x1-1/16 Offset Box Wrench

Fig. 11. OTC Early [3034] 15/16x1-1/16 Offset Box Wrench, with Insets for Side View and Marking Detail, ca. Late 1920s to Early 1930s.

Fig. 11 shows an early OTC [3034] 15/16x1-1/16 offset box wrench, marked only with the "OTC" logo.

The overall length is 16.5 inches, and the finish is plain steel.

This wrench is identified as model No. 3034 in the 1929 OTC catalog.

Note the distinctive tapered box ends of the wrench, a style also found in wrenches from P & C. An example can be seen as the P & C 2222-E 5/8x11/16 Offset Box-End Wrench.

Early 13/32x7/16 Short Box-End Wrench

Fig. 12. OTC Early 13/32x7/16 Short Box-End Wrench, with Inset for Side View.

Fig. 12 shows an early OTC short box wrench in an unusual 13/32x7/16 size, marked only with the "OTC" logo.

The overall length is 5.7 inches, and the finish is plain steel.

Open-End Wrenches

OTC E-1013 5/16x13/32 Open-End Wrench

Fig. 14. OTC E-1013 5/16x13/32 Open-End Wrench.

Fig. 14 shows an OTC E-1013 5/16x13/32 open-end wrench, stamped "Owatonna Tool Co." and "Owatonna, Minn." with "Made in U.S.A." on the shank. The shank also has a forged-in code "8740" visible at the left.

The overall length is 5.0 inches, and the finish is chrome plating.

OTC E-2225 11/16x25/32 Open-End Wrench

Fig. 15. OTC E-2225 11/16x25/32 Open-End Wrench, with Inset for Back Side Detail.

Fig. 15 shows an OTC E-2250 11/16x25/32 open-end wrench, stamped "Owatonna Tool Co." and "Made in U.S.A." with the OTC logo on the shank, with the model number and fractional sizes on the back side.

The overall length is 8.1 inches. The finish is chrome plating, with extensive losses due to wear.

OTC E-3640 1-1/8x1-1/4 Open-End Wrench

Fig. 16. OTC E-3640 1-1/8x1-1/4 Open-End Wrench, with Inset for Back Side Detail.

Fig. 16 shows an OTC E-3640 1-1/8x1-1/4 open-end wrench, stamped "Owatonna Tool Co." and "Made in U.S.A." with the OTC logo on the shank, with the model number and fractional sizes on the back side.

The overall length is 12.9 inches, and the finish is chrome plating.

OTC O-2428 3/4x7/8 Tappet Wrench

Fig. 17. OTC O-2428 3/4x7/8 Tappet Wrench, with Inset for back side.

Fig. 17 shows an OTC O-2428 3/4x7/8 tappet wrench, stamped "Owatonna Tool Co." and "Made in U.S.A." with the OTC logo on the shank, with the model number and fractional sizes on the back side.

The overall length is 9.4 inches, and the finish is chrome plating.

OTC B-12 3/8x3/8 Angle-Head Obstruction Wrench

Fig. 18. OTC B-12 3/8x3/8 Angle-Head Obstruction Wrench, with Inset for back side.

Fig. 18 shows an OTC B-12 3/8x3/8 obstruction wrench, stamped with the OTC logo and "Chrome-Vanadium Steel" on the shank.

The overall length is 5.5 inches, and the finish is nickel plating.

OTC No. 5 13/64x15/64 Ignition Wrench

OTC offered ignition wrenches in paired sizes with the same opening sizes but different offset angles. The next two figures show examples of a size pair.

Fig. 19. OTC No. 5 13/64x15/64 Ignition Wrench, with Inset for Back Side.

Fig. 19 shows an OTC No. 5 13/64x15/64 ignition wrench, stamped with the OTC logo and model on one side, with the fractional sizes on the back side.

The overall length is 3.1 inches, and the finish is nickel plating.

OTC No. 6 13/64x15/64 Ignition Wrench

Fig. 20. OTC No. 6 13/64x15/64 Ignition Wrench, with Inset for Back Side.

Fig. 20 shows an OTC No. 6 13/64x15/64 ignition wrench, stamped with the OTC logo and model on one side, with the fractional sizes on the back side.

The overall length is 3.1 inches, and the finish is nickel plating.

Combination Wrenches

OTC first offered combination wrenches in 1935 in four sizes from 7/16 to 5/8. Based on the illustration in catalog No. 26, these tools were Herbrand "MultiType" wrenches supplied as contract production.

By 1941 (catalog No. 32) OTC had changed to a different supplier for combination wrenches, and the wrenches were available in 16 sizes from C-12 (3/8) up to C-46 (1-7/16).

OTC C-12 3/8 Combination Wrench

Fig. 21. OTC C-12 3/8 Combination Wrench, with Inset for Back Side Detail.

Fig. 21 shows an OTC C-12 3/8 combination wrench, marked "Owatonna Tool Co" and "Made in U.S.A." with the OTC-Shield logo.

The overall length is 7.0 inches, and the finish is chrome plating with polished faces.

OTC C-22 11/16 Combination Wrench

Fig. 22. OTC C-22 1-1/8 Combination Wrench, with Inset for Side View.

Fig. 22 shows an OTC C-22 11/16 combination wrench, stamped "Owatonna Tool Co." and "Owatonna, Minn." with "Made in U.S.A." on the shank.

The overall length is 8.6 inches, and the finish is plain steel.

OTC C-36 1-1/8 Combination Wrench

Fig. 23. OTC C-36 1-1/8 Combination Wrench, with Inset for Side View.

Fig. 23 shows an OTC C-36 1-1/8 combination wrench, marked "Owatonna" and "USA" with the OTC logo.

The overall length is 15.9 inches, and the finish is chrome plating with polished faces.

Stub-Handle Box Wrenches

Stub-handle box wrenches were first offered in the 1936 catalog No. 28 and were available in straight, angled, and offset styles.

OTC offered tubular steel extension handles for the stub-handle wrenches, and the extension handles were provided with a drilled hole at each end to accept the locking pins of the stub handles.

OTC MA-60 1-7/8 Single-Box Heavy Duty Wrench

Fig. 13. OTC MA-60 1-7/8 Single-Box Heavy Duty Wrench, with Inset for Marking Detail, ca. 1941+.

Fig. 13 shows an OTC MA-60 1-7/8 single-box wrench, stamped with "Owatonna Tool Co. Owatonna, Minn." and "Made in U.S.A." on the shank.

The overall length is 13.6 inches, and the finish is plain steel.

The stub handle is fitted with a locking button to engage a hole in a tubular extension handle.

Flex-Box Wrenches

By 1941 OTC was offering flex-box wrenches in six sizes from F-1214 (3/8x7/16) up to F-2628 (13/16x7/8), and by 1947 a seventh size F-3032 (15/16x1) had become available.

F-1820 9/16x5/8 Flex-Box Wrench

Fig. 24. OTC F-1820 9/16x5/8 Flex-Box Wrench, with Inset for Top View, ca. 1941+.

Fig. 24 shows an OTC F-1820 9/16x5/8 flex-box wrench, stamped "Owatonna Tool Co. Owatonna, Minn." and "Made in U.S.A." on the raised panel.

The overall length is 9.7 inches fully extended, and the finish is cadmium plating.

F-2224 11/16x3/4 Flex-Box Wrench

Fig. 25. OTC F-2224 11/16x3/4 Flex-Box Wrench, with Inset for Top View, ca. 1941+.

Fig. 25 shows an OTC F-2224 11/16x3/4 flex-box wrench, marked "Owatonna Tool Co. Owatonna, Minn." and "Made in U.S.A." on the raised panel.

The overall length is 11.0 inches, and the finish is plain steel.

F-2628 13/16x7/8 Flex-Box Wrench

Fig. 26. OTC F-2628 13/16x7/8 Flex-Box Wrench, with Insets for Top View and Back Side Detail, ca. 1941+.

Fig. 26 shows an OTC F-2628 13/16x7/8 flex-box wrench, marked "Owatonna Tool Co." on the raised panel, with "USA" on the back side.

The overall length is 12.3 inches fully extended, and the finish is chrome plating with polished panels and sockets.

F-3032 15/16x1 Flex-Box Wrench

Fig. 27. OTC F-3032 15/16x1 Flex-Box Wrench, with Insets for Top View and Back Side Detail, ca. 1947+.

Fig. 27 shows an OTC F-3032 15/16x1 flex-box wrench, stamped "Owatonna Tool Co." with the OTC logo on the raised panel, with "Made in U.S.A." and the fractional sizes on the back side.

The overall length is 14.3 inches fully extended, and the finish is chrome plating with polished panels and sockets.

Sockets and Drive Tools

OTC H-183 1/2-Drive Speeder

Fig. 28. OTC H-183 1/2-Drive Speeder, with Inset for Marking Detail, ca. 1942-1945

Fig. 28 shows a 1/2-drive OTC H-183 speeder, stamped "Owatonna Tool Co. Owatonna, Minn." and "Made in U.S.A." on the end piece.

The overall length is 15.8 inches, and the finish is cadmium plating.

OTC H-187 1/2-Drive Sliding Tee Handle

Fig. 29. OTC H-187 1/2-Drive Sliding Tee Handle, with Insets for Marking Detail.

Fig. 29 shows a 1/2-drive OTC H-187 sliding Tee handle, stamped "Owatonna Tool Co. Owatonna, Minn." and "Made in U.S.A." on the sliding head.

The overall length is 10.0 inches, and the finish is cadmium plating.

OTC [41-H-1500] 1/2-Drive Flex Handle

Fig. 30. OTC [41-H-1500] 1/2-Drive 10 Inch Flex Handle, with Insets for Side View and Detail, ca. 1941-1945.

Fig. 30 shows a 1/2-drive OTC 10 inch flex handle produced for a military tool kit, stamped "Owatonna Tool Co. Owatonna, Minn." and "Made in U.S.A." on the shank. Although not marked with a model number, the tool was identified as the "41-H-1500 Handle" illustrated in publication ORD 6 SNL G-27, a catalog of the "Tool-Set, General Mechanics'" from the WWII era.

The overall length is 10.8 inches, and the finish is cadmium plating.

The handle is equipped with a cross-bar hole and has a 1/2-drive end broaching, allowing use as a Tee-handle or extension.

The lower inset shows a side view of the tool, clearly illustrating the trimming marks left by the drop-forge trimming operation. The fairly rough finish was appropriate for a tool being made for a military tool kit, as the emphasis was on high-volume low-cost production.

The full description for the tool in the ORD 6 SNL G-27 catalog is "HANDLE, socket wrench, hinged, 1/2 in. sq-drive., length 10 1/2 in.", and the catalog shows a $1.15 unit price.

OTC H-161 1/2-Drive Ratchet

Fig. 31. OTC H-161 1/2-Drive Ratchet, with Inset for Side View.

Fig. 31 shows a 1/2-drive OTC H-161 ratchet, with markings "Owatonna Tool Co. Owatonna, Minn." and "Made in U.S.A." stamped on the shank.

The overall length is 11.3 inches, and the finish is plain steel.

OTC H-160 1/2-Drive Rotating-Head Ratchet

Fig. 32. OTC H-160 1/2-Drive Rotating-Head Ratchet, with Insets for Marking Detail, ca. 1935+.

Fig. 32 shows a 1/2-drive OTC H-160 "flex" ratchet with a distinctive rotating head, stamped "Owatonna Tool Co. Owatonna, Minn." and "Made in U.S.A." on the shank.

The overall length is 11.9 inches, and the finish is cadmium plating.

This unusual style of flex-head ratchet allows the head to rotate through 360 degrees, providing the flexibility to operate at any angle in tight places. The OTC catalogs called these "Flex Ratchets", and models of this type (in 3/8-drive as well) were offered as early as 1935 in OTC catalog No. 26. Although this model was offered at a relatively early date, the design borrows from the even earlier Cunha 1919 patent, shown as the Peerless Wrench Cunha Patent Ratchet.

OTC H-260 3/8-Drive Rotating-Head Ratchet

Fig. 33. OTC H-260 3/8-Drive Rotating-Head Ratchet, with Inset for Side View.

Fig. 33 shows the 3/8-drive version of the rotating head ratchet, an OTC H-260 flex ratchet stamped with the OTC logo.

The overall length is 7.0 inches, and the finish is chrome plating.

The ratchet mechanism has a 24-tooth drive gear and uses dual pawls for greater strength. The ratchet action can be reversed by pushing the drive stud through to the other side.

As with other OTC ratchets, the ratchet head has been permanently sealed by crimping the edges.

OTC H-275 3/8-Drive Flex Handle

Fig. 34. OTC H-275 3/8-Drive Flex Handle, with Inset for Marking Detail.

Fig. 34 shows a 3/8-drive OTC H-275 flex handle, marked with the OTC logo on the shank.

The overall length is 8.3 inches, and the finish is plain steel.

OTC P-61 1.5-Hex Drive Stub-Handle Ratchet

Fig. 35. OTC P-61 1.5 Hex Drive Ratchet, with Inset for Side View.

Fig. 35 shows an OTC P-61 1.5-hex drive stub-handle ratchet, marked "Owatonna Tool Co. Owatonna, Minn." and "Made in U.S.A." on the shank.

The overall length is 11.3 inches, and the finish is chrome plating.

The stub handle is fitted with a locking button to engage a hole in a tubular extension handle.

The P-61 was a heavy-duty ratchet intended for several applications. The 1-1/2 inch hexagonal opening could be used directly on the hex nuts for some large OTC pullers.

In addition, with a suitable adapter the ratchet could be used with 3/4-drive and 1 inch drive socket sets.

OTC P61-6 1.5 Hex To 3/4 Square Drive Adapter Plug

Fig. 36. OTC P-61-6 1.5 Hex To 3/4 Square Adapter Plug.

Fig. 36 shows one of the adapters available for the P-61 ratchet, an OTC P61-6 drive adapter going from 1.5 hex to 3/4 square drive. The adapter is marked with the OTC logo and model number.

The overall length is 3.0 inches, and the finish is chrome plating.

Specialty Tools

Specialty Wrenches

Early 9/16x5/8 Half-Moon Box Wrench

Fig. 37. OTC Early 9/16x5/8 Half-Moon Box Wrench.

Fig. 37 shows an early OTC 9/16x5/8 half-moon box wrench, probably intended for starter and manifold service. The wrench is unmarked except for the "OTC" logo.

The overall length is 7.1 inches, and the finish is plain steel.

OTC RB-2428 3/4x7/8 Ratcheting Box Wrench

Fig. 38. OTC RB-2428 3/4x7/8 Ratcheting Box Wrench, with Insets for Side View and Back Side Detail, ca. 1947-1950.

Fig. 38 shows an OTC RB-2428 3/4x7/8 ratcheting box wrench, stamped "Owatonna Tool Co." and "Made in U.S.A." with the OTC logo on the front, with "Pat. App." on the back side.

The overall length is 9.2 inches, and the finish is chrome plating.

The top inset shows the laminated and riveted construction of the wrench, allowing the maker to be identified as A&E Manufacturing, a major producer of ratcheting box wrenches from the 1950s onward.

The pending status refers to patent #2,500,835, filed by John W. Lang in 1947 and issued in 1950.

The round shank is equipped with a push-button locking pin to engage an extender handle.

OTC 7051 1-3/8x1-1/2 Speciaty Open-End Wrench

Fig. 39. OTC 7051 1-3/8x1-1/2 Open-End Wrench, ca. Late 1970s to 1980s.

Fig. 39 shows an OTC 7051 1-3/8x1-1/2 open-end wrench, stamped with the OTC logo on the raised panel.

The overall length is 9.9 inches, and the finish is chrome plating.

This wrench is listed in the 1978 OTC catalog AM-75 for front-end work, specifically for adjusting the camber on Cadillac models with ball-joint suspensions.

OTC 505 1/2 Distributor Wrench

Fig. 40. OTC 505 1/2 Distributor Wrench, with Insets for Construction and Marking Detail, ca. Late 1950s to 1960s.

Fig. 40 shows an OTC 505 1/2 distributor wrench, stamped with the OTC logo and model number around the shank.

The overall length is 9.5 inches, and the finish is cadmium plating.

This wrench is listed in the 1959 OTC catalog A-9 as a distributor lock-nut wrench for Cadillac and Studebaker service.

Specialty Pliers

Bent Longnose Specialty Pliers

Fig. 41. OTC Bent Longnose Specialty Pliers, with Insets for Side View and Jaw Detail, ca. 1935.

Fig. 41 shows a rarely-seen pair of OTC bent longnose specialty pliers, constructed with a groove in the tip for handling pins and wires.

The overall length is 7.9 inches, and the finish is polished steel.

The lower inset shows a closeup of the jaws, with a matching groove in each side to help handle small cylindrical objects.

These pliers were listed in OTC catalog No. 26 from 1935, and were available in both straight and bent-nose styles.

614 Snap-Ring Pliers

Fig. 42. OTC 614 Snap-Ring Pliers.

Fig. 42 shows a pair of OTC 614 snap-ring pliers, marked "Owatonna Tool Co." with "Owatonna, Minn." and "Made in U.S.A." on the handle.

The overall length is 8.3 inches, and the finish is plain steel.

714 Snap-Ring Pliers

Fig. 43. OTC 714 Snap-Ring Pliers.

Fig. 43 shows a pair of OTC 714 snap-ring pliers, marked "Owatonna Tool Co." with "Owatonna, Minn." and "Made in U.S.A." on the handle.

The overall length is 7.2 inches, and the finish is plain steel.

Other Specialty Tools

OTC 776 Brake Spoon

Fig. 44. OTC 776 Brake Spoon, with Inset for Side View.

Fig. 44 shows an OTC 776 brake spoon, stamped with the OTC logo and "Made in U.S.A." on the shank.

The overall length is 7.0 inches, and the finish is plain steel.

OTC A-100 Valve Spring Lifter

Fig. 45. OTC A-100 Valve Spring Lifter, with Inset for Side View.

Fig. 45 shows an OTC A-100 valve spring lifter, stamped with the OTC logo and "Owatonna Tool Co. Owatonna Minn.", plus "Made in U.S.A." and a "Pat. No. 2,119,128" patent notice.

The overall length is 8.5 inches, and the finish is black oxide.

The patent notice refers to patent #2,119,128, filed by I.J. Clark in 1937 and issued in 1938. This patent was used by other tool makers as well as OTC, and an example can be seen in the Herbrand VL-540 Valve Spring Lifter.