The Owatonna Tool Company (OTC) [Under Construction]

Table of Contents

• Introduction
• Pullers and Presses
• Wrenches
• Sockets and Drive Tools
• Specialty
• References and Resources
• What's New (Last Updated July 3, 2008)
  Recent changes to this page:

  • 07/03/2008: Added a OTC H-260 3/8-Drive Rotating-Head Ratchet.
  • 06/15/2008: Added a OTC No. 6 Ignition Wrench.
  • 06/14/2008: Added a OTC No. 5 Ignition Wrench.
  • 06/03/2008: Added a OTC Early 1/2-Drive Flex-Head Breaker Bar.
  • 04/05/2008: Added a OTC 13/32x7/16 Short Box Wrench.
  • 01/27/2008: Added a OTC No. 1002 Gear Puller.
  • 12/31/2007: Added a OTC A-100 Valve Spring Lifter.
  • 11/28/2007: Updated catalog section.
  • 10/30/2007: Added a OTC Early No. 1001 Gear Puller.
  • 10/23/2007: Added a OTC No. 1001 Gear Puller.
  • 09/12/2007: Added a OTC Half-Moon Box Wrench.
  • 06/25/2007: Added a OTC H-275 3/8-Drive Flex-Head Breaker Bar.
  • 05/09/2007: Added a OTC C-36 Combination Wrench.
  • 04/10/2007: Added an OTC P-61 1.5 Hex Drive Ratchet and an OTC P61-6 1.5 Hex To 3/4 Square Adapter Plug.
  • 04/06/2007: Added a OTC 776 Brake Spoon.
  • 04/03/2007: Added a OTC 1000 Gear Puller.
  • 04/02/2007: Added OTC 714 Snap-Ring Pliers.
  • 03/07/2007: Added OTC H-161 1/2-Drive Ratchet.
  • 03/06/2007: Added OTC 614 Snap-Ring Pliers.
  • 02/13/2007: Added patent table, added a OTC H-160 Rotating-Head Ratchet.
  • 02/12/2007: Added a OTC MA-60 Single-Box Wrench.
  • 02/06/2007: Added OTC Bent Longnose Pliers.
  • 02/02/2007: Added catalog table.
  • 12/17/2006: Added page, not much content yet.

Introduction

Company History

Patents

Trademarks

OTC registered several trademarks, beginning with the "OTC" mark, with the first use date listed as Sept. 1, 1925. The "Grip-O-Matic" and "Push-Puller" trademarks were registered with the first use in 1940.

Tool Identification

Pullers and Presses

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

Fig. 1. OTC No. 1000 Gear Puller.

Fig. 1 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. 2. OTC Early No. 1001 Two-Arm Reversible Gear Puller.

Fig. 2 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. 3. OTC No. 1001 Two-Arm Reversible Gear Puller.

Fig. 3 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. 4. OTC No. 1002 Two-Arm Reversible Gear Puller, with Inset for Marking Detail.

Fig. 4 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.

Wrenches

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

Fig. 5. OTC Early 9/16x5/8 Half-Moon Box Wrench.

Fig. 5 at the left 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.

Early 13/32x7/16 Short Box Wrench

Fig. 6. OTC Early 13/32x7/16 Short Box Wrench, with Inset for Side View.

Fig. 6 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.

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

Fig. 7. OTC F-2224 11/16x3/4 Flex-Box Wrench, with Inset for Side View.

Fig. 7 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.

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

Fig. 8. OTC No. 5 13/64x15/64 Ignition Wrench, with Inset for Reverse.

Fig. 8 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 reverse.

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

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

Fig. 9. OTC No. 6 13/64x15/64 Ignition Wrench, with Inset for Reverse.

Fig. 9 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 reverse.

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

OTC C-12 Combination Wrench

Fig. 10. OTC C-12 3/8 Combination Wrench, with Inset for Reverse Detail.

Fig. 10 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-36 Combination Wrench

Fig. 11. OTC C-36 1-1/8 Combination Wrench, with Inset for Side View.

Fig. 11 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.

OTC MA-60 Single-Box Heavy Duty Wrench

Fig. 12. OTC MA-60 1-7/8 Single-Box Heavy Duty Wrench, with Inset for Marking Detail.

Fig. 12 shows an OTC MA-60 1-7/8 single-box wrench, with markings "Owatonna Tool Co. Owatonna, Minn." and "Made in U.S.A." stamped on the shank.

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

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

Sockets and Drive Tools

OTC Early 1/2-Drive Flex-Head Breaker Bar

Fig. 13. OTC Early 1/2-Drive 10 Inch Flex-Head Breaker Bar, with Insets for Side View and Detail, ca. 1930-1934.

Fig. 13 shows a rare early 1/2-drive OTC flex-head breaker bar in the 10 inch nominal size, stamped "Owatonna Tool Co. Owatonna, Minn." and "Made in U.S.A." on the shank.

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. This drop-forged construction was used to estimate the manufacturing date for this tool, based on catalog descriptions of earlier (1929) and later (1935) models. The 1929 breaker bars are described as being hand-forged, and by 1935 OTC was providing a polished steel finish for these tools.

OTC H-161 1/2-Drive Ratchet

Fig. 14. OTC H-161 1/2-Drive Ratchet, with Inset for Side View.

Fig. 14 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. 15A. OTC H-160 1/2-Drive Rotating-Head Ratchet, with Insets for Marking Detail, ca. 1935+.

Fig. 15A 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 flexibilty 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 Cunha Patent Ratchet.

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

Fig. 15B. OTC H-260 3/8-Drive Rotating-Head Ratchet, with Inset for Side View.

Fig. 15B 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-Head Breaker Bar

Fig. 16. OTC H-275 3/8-Drive Breaker Bar, with Inset for Marking Detail.

Fig. 16 shows a 3/8-drive OTC H-275 flex-head breaker bar, 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 Ratchet

Fig. 17. OTC P-61 1.5 Hex Drive Ratchet, with Inset for Side View.

Fig. 17 shows an OTC P-61 1.5 hex drive 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 P-61 is a heavy-duty ratchet intended for several applications. The 1-1/2 hex opening can be used directly on the hex nuts for some large OTC pullers. In addition, with a suitable adapter the ratchet can 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. 18. OTC P-61-6 1.5 Hex To 3/4 Square Adapter Plug.

Fig. 18 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

Bent Longnose Specialty Pliers

Fig. 19. OTC Bent Longnose Specialty Pliers, with Insets for Side View and Jaw Detail, ca. 1935.

Fig. 19 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. 20. OTC 614 Snap-Ring Pliers.

Fig. 20 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. 21. OTC 714 Snap-Ring Pliers.

Fig. 21 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.

OTC 776 Brake Spoon

Fig. 22. OTC 776 Brake Spoon, with Inset for Side View.

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

OTC A-100 Valve Spring Lifter

Fig. 23. OTC A-100 Valve Spring Lifter, with Inset for Side View.

Fig. 23 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.

References and Resources

Photographs and observations of particular tools are based on items in my personal collection.

Catalog Coverage

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

Patents and Trademarks

Patent information was obtained from the U.S. Patents and Trademarks Office (USPTO) web site at uspto.gov. Patent documents were obtained from sites offering free downloads, notably freepatentsonline.com.

Feedback

If any readers have additional information about OTC, please let us know via the "Contact Us" link at the bottom of any page. Your comments and suggestions are welcome as well.