The Frank Mossberg Company

Table of Contents

• Introduction
• Early Tools
• Sockets and Drive Tools
• General Service and Automotive Specialty Tools
• Later Socket Development
• The APCO Merger and Later Tools
• References and Resources
• What's New (Last Updated Oct. 22, 2009)
  Recent changes to this page:

  • 10/22/2009: Added a Mossberg No. 470 Alligator Wrench.
  • 10/21/2009: Minor reorganization, added a Mossberg No. 210 Open-End Wrench.
  • 10/20/2009: Added a Mossberg No. 253 Open-End Wrench.
  • 10/19/2009: Added a Mossberg No. 275 Open-End Wrench.
  • 09/26/2009: Added a APCO-Mossberg 975 Single-Offset Box Wrench.
  • 09/04/2009: Added a Mossberg "Ever-Wear" 5/8 Socket.
  • 08/26/2009: Added a Mossberg No. 355 Ratchet.
  • 08/24/2009: Split into two pages, added a Mossberg No. 240 Open-End Wrench.
  • 08/19/2009: Added a Mossberg [No. 351] Extension from No. 30 Set.
  • 08/18/2009: Added a Mossberg No. 30 Pressed-Steel Socket Set.
  • 08/11/2009: Updated socket set table.
  • 08/09/2009: Added a Mossberg [No. 310] 1/2-Drive Folding Handle.
  • 08/05/2009: Added a Mossberg No. 6 Pressed-Steel Socket Set.
  • 08/04/2009: Added summary table for socket sets.
  • 07/25/2009: Added a APCO-Mossberg No. 206 Tappet Wrench.
  • 07/24/2009: Added a Mossberg No. 232 Open-End Wrench.
  • 06/17/2009: Added a Mossberg K9 9 Inch Bicycle Wrench.
  • 05/08/2009: Added a Mossberg "C" Bicycle Wrench.
  • 04/20/2009: Minor reorganization of sections, added Cover Detail for "Auto-Cle" No. 1 Socket Set, Mossberg "Auto-Cle" 1/2-Drive Hex Sockets, and a Mossberg "Auto-Cle" 1/2-Drive 10 Inch Extension.
  • 04/19/2009: Added a Mossberg "Auto-Cle" No. 1 Socket Set.
  • 04/17/2009: Added a Mossberg "Sterling" No. 30 Bicycle Wrench.
  • 04/01/2009: Added a Mossberg No. 253 Open-End Wrench.
  • 03/20/2009: Added a APCO-Mossberg 3011 Offset Box Wrench.
  • 03/19/2009: Added a APCO-Mossberg 979 Single-Offset Box Wrench.
  • 02/26/2009: Added a APCO-Mossberg 971 Single-Offset Box Wrench.
  • 02/17/2009: Added date code inset for APCO-Mossberg 3014 Offset Box Wrench.
  • 02/07/2009: Expanded company history, added advertisement of No. 45 socket set.
  • 02/04/2009: Updated company history.
  • 01/07/2009: Added a Mossberg 23/32x25/32 Double Socket Wrench.
  • 12/10/2008: Added a Mossberg 1/2-Drive Ratchet Adapter.
  • 11/16/2008: Added a Auto-Cle 1/2-Drive Ratchet.
  • 04/06/2008: Added a Mossberg "Sterling" No. 2 Bicycle Wrench.
  • 04/02/2008: Added a Mossberg No. 654 Valve Spring Lifter.
  • 03/29/2008: Added discussion of Pressed-Steel Socket Sizes.
  • 03/09/2008: Added a Mossberg Z-Shaped 19/32 Double Socket Wrench.
  • 03/04/2008: Added a Mossberg 371 11/16-Drive Adapter.
  • 01/31/2008: Added a Mossberg No. 355 Non-Reversible Ratchet.
  • 01/25/2008: Added a APCO-Mossberg 3014 Offset Box Wrench.
  • 01/23/2008: Added a Mossberg 715B Open-End Wrench.
  • 01/07/2007: Updated catalog resources.
  • 01/03/2007: Updated catalog resources.
  • 11/30/2007: Added a Mossberg Z-Shaped 17/32x21/32 Double Socket Wrench.
  • 11/09/2007: Added a Mossberg 2149 Socket Wrench.
  • 08/13/2007: Added a Mossberg 260-A Open-End Wrench.
  • 07/18/2007: Added a APCO-Mossberg 974 Single-Offset Box Wrench.
  • 05/21/2007: Added a Mossberg Male Drive Sockets.
  • 05/04/2007: Added a Mossberg 645 Ratcheting Box Wrench.
  • 05/03/2007: Added an APCO Early Double-Hex Box Wrench.
  • 02/19/2007: Added a Mossberg No. 1235 S-Shaped Wrench.
  • 02/03/2007: Added a Mossberg No. 234 Open-End Wrench.
  • 01/09/2007: Added a Mossberg F-2 Bicycle Wrench.
  • 01/04/2007: Added a Mossberg No. 11 Diamond Bicycle Wrench.
  • 11/29/2006: Added a Mossberg No. 1 Sterling Bicycle Wrench.
  • 11/21/2006: Added an Mossberg A1 Bicycle Wrench and a Mossberg Folding Drive Handle.
  • 11/19/2006: Added a APCO-Mossberg 1/2-Drive Extension.
  • 11/15/2006: Added a Mossberg No. 355 Non-Reversible Ratchet.
  • 11/14/2006: Added a Mossberg 624 Ratcheting Connecting-Rod Wrench.
  • 11/13/2006: Added Mossberg No. 363 Speeder Socket Wrench, a Mossberg No. 367 1/2-Drive Speeder, and a APCO-Mossberg 976 Single-Offset Wrench.
  • 11/12/2006: Added Mossberg Heavy-Wall Sockets.
  • 11/11/2006: Added a Mossberg 422 Spark Plug Socket.
  • 11/10/2006: Added a Double-Male Universal.
  • 11/09/2006: Started patent table, added a No. 351 Extension and a 1/2-Drive Socket.
  • 11/08/2006: Added a No. 10 Socket Set.
  • 08/19/2006: Added a rare 631 Ratcheting Socket Wrench.
  • 08/17/2006: Added a 623 Socket Wrench.
  • 08/15/2006: Added page, no content yet.

Introduction

The Frank Mossberg Company was an important early maker of wrenches, automotive tools, and especially interchangeable socket sets. In the years before 1920, Mossberg along with Walden-Worcester both defined and dominated the early market for socket sets, and their products laid the groundwork for the later development of interchangeable socket tools.

Company History

Frank Mossberg was a notable inventor and businessman in Attleboro, Massachusetts, a center for jewelry manufacturing in the 19th century. Mossberg was born in Wermland, Sweden in 1858 and had immigrated to America in 1882. After working as a draftsman for Brown & Sharpe for a few years, he began his first manufacturing business in 1889 as the Mossberg Manufacturing Company in Attleboro, Massachusetts. (Another early business venture is referred to as the Mossberg Wrench Company and is presumed to be a subsidiary of Mossberg Manufacturing, although the exact relationship is not yet clear.)

The company was initially a maker of tools for the jeweler's trade, but by the early 1890s had begun producing several styles of adjustable bicycle wrenches, which were very popular tools at the time. Several patents for adjustable wrenches were issued to Mossberg in the 1890s, with assignments made to the Mossberg Wrench Company.

In 1899 Frank Mossberg and other investors founded the Frank Mossberg Company to manufacture tools, with the intended production of pipe wrenches, bicycle wrenches, and related items. The company was initially located in Providence, Rhode Island and operated independently of Mossberg's earlier business(es), but by 1900 the company had moved to Attleboro, and then in 1901 the earlier business operations were merged into the Frank Mossberg Company. By the early 1900s the company was producing bicycle wrenches in a number of styles, with names such as Sterling and Diamond.

The Auto-Cle Line

In 1908 the company made a key acquisition with the purchase of the "Auto-Cle" line of automotive socket wrenches from the Quincy, Manchester, Sargent Company. These socket wrench sets consisted of pressed-steel sockets with a ratcheting drive tool, and were based on patents #751,055 and #RE12,379, issued in 1904 and 1905 respectively. Mossberg had previously been the contract manufacturer for the Auto-Cle socket sets and realized their significant market potential. The Auto-Cle acquisition was the starting point for a very successful line of socket wrench products, and Mossberg made numerous improvements and additions over the years.

In 1909 the Frank Mossberg Company built a significant new factory in Attleboro, with $50,000 of funding provided by a local group of business investors. This factory project is noted in the August, 1909 issue of The Horseless Age on page 186 at the top center. The article describes the factory as a two-story brick building of dimensions 60 by 290 feet, with a separate power plant included as well. Construction was expected to be complete by December 1 of that year.

The expansion of the automobile industry created great demand for automotive service tools, and in the years from 1910 to 1920 the Frank Mossberg Company became a significant maker of automotive specialty tools. These tools consisted primarily of fixed socket wrenches in many shapes and sizes, and Mossberg was probably second only to Walden-Worcester as a producer of such tools.

The Late Teens

In early 1919 Mossberg released an important new product, the No. 45 Socket Wrench Set, which combined a 1/2 square drive speeder handle with a selection of heavy-duty sockets. This socket set was featured in an advertisement on page 137 of the January 1919 issue of Popular Science Monthly, and the illustration shows the speeder handle together with a generous selection of sockets.

The No. 45 set was clearly intended for professional mechanics, who needed the faster operation of a speeder handle plus the stronger sockets for everyday use. (Modern readers may strain to imagine a time when there were no air-powered drive tools, but at that time a speeder was the fastest way to spin off a nut.) And with the interchangeable sockets, the No. 45 set could fit a wide range of nut sizes at a much lower cost and weight than a comparable set of fixed socket wrenches.

The timing for this set was critical too, as in early 1919 Blackhawk Manufacturing was just getting started (and its name hadn't even been decided yet), and the Snap-On Wrench Company was more than a year in the future. If the No. 45 socket set had turned out to be a huge commercial success, it very possibly could have significantly altered the balance of competition in the 1920s.

Later Developments

During the 1920s the company continued to expand its automotive service tools line. In 1927 the company was reorganized as the APCO-Mossberg Company by merger with APCO (The Auto Parts Company) of Providence, Rhode Island. APCO was a maker of parts and specialty tools for the Model T Ford, and some examples of their products can be seen in a later section.

Sometime during the 1930s APCO-Mossberg decided to drop their general service tools, perhaps because of excess competition, and became instead a specialized maker of torque measurement products. The APCO-Mossberg torque products remained in production for many years.

Patents

Frank Mossberg was extremely prolific as an inventor, and the following table lists only the tool-related patents, representing a small fraction of his total output.

Trademarks

A search of the USPTO trademark records found only one trademark registered by Frank Mossberg, the M-Diamond logo. The trademark was filed in 1907 and listed the first use as November 1902.

Early Tools

Early Model C Bicycle Wrench

Fig. 1. Mossberg Model C Bicycle Wrench, with Insets for Side View and Marking Detail, ca. 1895-1899.

Fig. 1 shows an early Mossberg "C" bicycle wrench, stamped "Mossberg Wrench Co." and "Attleboro, Mass. U.S.A" with "[Pat.] Nov. 19 & Dec. 31, '95" patent dates. (The left side of the markings was stamped very lightly and is difficult to read.)

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

The first patent date refers to patent #550,025 filed by Frank Mossberg in 1894. The patent describes an adjustable wrench with a thin profile made possible by the laminated steel construction.

The later date refers to patent #552,325, filed by Frank Mossberg in 1895.

"Sterling" No. 1 Bicycle Wrench

Fig. 2. Mossberg "Sterling" No. 1 Bicycle Wrench, ca. 1900-1902.

Fig. 2 shows a Mossberg "Sterling" No. 1 bicycle wrench, stamped "Manf'd by Frank Mossberg Co." and "Attleboro, Mass. U.S.A" with a "Pat. Nov. 13, 00" patent date.

The overall length is 5.0 inches, and the finish is fully polished with nickel plating.

The patent date corresponds to patent #661,810, filed by Frank Mossberg in 1900 and issued later that year.

The absence of the M-Diamond trademark suggests that this is an early tool, made before the general use of the trademark logo.

"Sterling" No. 2 Bicycle Wrench

Fig. 3. Mossberg "Sterling" No. 2 Bicycle Wrench.

Fig. 3 shows a later Mossberg "Sterling" No. 2 bicycle wrench, stamped with the M-Diamond logos on either side of the model number, with "Manf'd by Frank Mossberg Co." and "Attleboro, Mass. U.S.A" at the end of the shank.

The overall length is 6.5 inches, and the finish is polished nickel, but with some loss due to wear and rust.

The wrench is also stamped with a "Pat. Nov. 13, 00" patent date, corresponding to patent #661,810, filed by Frank Mossberg in 1900 and issued later that year.

"Sterling" No. 30 Bicycle Wrench

Fig. 4. Mossberg "Sterling" No. 30 Bicycle Wrench, with Inset for Reverse Detail.

Fig. 4 shows a Mossberg "Sterling" No. 30 bicycle wrench, stamped with the M-Diamond logo above the model number. The reverse is stamped "Manf'd by Frank Mossberg Co." and "Attleboro, Mass. U.S.A" with "Pat'd. Nov. 13, 00", "Pat'd. Mar. 11, 02", and "Pat. Applied For" patent notices.

The overall length is 7.9 inches, and the finish is polished nickel, with minor losses due to wear and rust.

The patent dates correspond to patents #661,810 and and #695,072, filed by Frank Mossberg in 1900 and 1901, respectively.

"Diamond" No. 11 Bicycle Wrench

Fig. 5. Mossberg "Diamond" No. 11 Bicycle Wrench.

Fig. 5 shows a Mossberg "Diamond" No. 11 bicycle wrench, marked "Frank Mossberg Co." and "Attleboro Mass. U.S.A" with M-Diamond logos on each side, and with patent notations "Pat'd. Nov. 13, 00" and "Pat'd. Mar. 11, 02".

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

The patent dates refer to patents #661,810 and #695,072, both of which describe methods of constructing adjustable wrenches of this design.

A-1 Bicycle Wrench

Fig. 6. Mossberg A-1 Bicycle Wrench.

Fig. 6 shows a Mossberg A-1 bicycle wrench, marked with the M-Diamond logo and patent notations "Pat. Nov. 13, 00 Mar. 11, 02".

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

The patent dates refer to patents #661,810 and #695,072, both of which describe methods of constructing adjustable wrenches of this design.

F-2 Bicycle Wrench

Fig. 7. Mossberg F-2 Bicycle Wrench.

Fig. 7 shows a Mossberg F-2 bicycle wrench, stamped with two M-Diamond logos and the patent notations "Pat. Nov. 13, 00 Mar. 11, 02".

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

K-8 8 Inch Bicycle Wrench

Fig. 8. Mossberg K-8 8 Inch Bicycle Wrench, ca. 1905.

Fig. 8 shows a rare Mossberg K-8 8 inch bicycle wrench, marked "Made in U.S.A." with the M-Diamond logo, and with patent notations "Patd. Nov. 13, 00 Mar. 11, 02".

The overall length is 7.9 inches.

One unusual feature is that the wrench body appears to be constructed of a copper alloy, as can be seen in the bright areas where the greenish tarnish has been removed.

K-9 9 Inch Bicycle Wrench

Fig. 9. Mossberg K-9 9 Inch Bicycle Wrench, ca. Early 1900s.

Fig. 9 shows a rare Mossberg K-9 9 inch bicycle or auto wrench, stamped "Manf'd by Frank Mossberg Co." and "Attleboro, Mass. U.S.A." with two M-Diamond logos bracketing the model number.

The overall length is 9.0 inches and the maximum opening is about 2.1 inches. The finish is plain steel with traces of nickel plating.

Although we've called this a "bicycle wrench", the larger size suggests that it may have been intended primarily for motorcycle or automotive service.

Sockets and Drive Tools

Mossberg was a pioneer in the development and production of sockets and drive tools, and their earliest product in this area was the "Auto-Cle" line of socket sets, first offered probably around 1905. Initially Mossberg was the contract manufacturer for the Auto-Cle line, but within a few years had purchased the rights to the patents and brand for the product line.

The sockets in the early Mossberg sets were made of pressed steel, and the drive ends were cleverly sized to allow being driven either on the outside (approximately 11/16 square), or from the inside as 1/2 square drive. This drive configuration quickly became a standard, and sockets from other early makers (such as Walden-Worcester) were generally interchangeable.

By 1912 Frank Mossberg had filed a patent for a reversible ratchet to drive the sockets, and the resulting socket sets with reversible ratchets became best sellers of their time.

Size Conventions for Pressed-Steel Sockets

Before proceeding to show examples of the socket sets, we'll first take a look at the somewhat odd size conventions used for pressed-steel sockets. This is an area that will probably cause as much confusion for modern readers as it likely did for early auto owners or "automobilists", as they were sometimes called.

Readers familiar with early Model T socket sets may have wondered about the numerous "oddball" socket sizes in 32nds, sizes such as 17/32 or 23/32 that are seldom seen today. Based on the socket sizes, you might have concluded that the early automobiles used a lot of strange fastener sizes.

However, if you check the open-end wrenches from the same time era, these tools don't include all of the opening sizes seen on sockets. (Keeping in mind that wrench openings were marked by a U.S.S. or S.A.E. size.) So if a Model T really used 17/32 or 23/32 nuts, why weren't these sizes available in open-end wrenches?

This discrepancy turns out to be due to pressed-steel socket sizes being specified as 1/32 oversize, apparently an allowance for the manufacturing tolerance. This means that a 17/32 pressed-steel socket would be specified for an (across-flats) 1/2 inch nut, for which a modern 1/2 socket would work fine. This same nut would use an open-end wrench marked as "1/4 U.S.S." or "5/16 S.A.E." under the old size conventions.

So in reality the Model T didn't have any 17/32 or 23/32 nuts. The early automobiles used a mix of fasteners with sizes following the U.S.S., S.A.E., or Hex Capscrew conventions, which use a few of the 32nd sizes, but the "strange" sizes appear only when the 1/32 oversize socket allowance is added. Open-end wrenches (and modern sockets) don't need to use an explicit oversize allowance, as the manufacturing tolerances allow for a small oversize to be hidden in the nominal size.

Table 2. Pressed-Steel Hex Socket Sizes for U.S.S., S.A.E., and Hex Capscrew Nuts

To help further clarify the situation, we've added a table showing the recommended pressed-steel socket size for the commonly used fasteners, along with the corresponding across-flats nut (or bolt) size. The information in Table 2 is from a 1922 Marwedel catalog listing for Mossberg sockets, and the catalog clearly states that a 1/32 clearance will be added if the sockets are ordered by nut size.

Keep in mind that the above table applies only to pressed-steel sockets -- later sockets were made with a broaching or forging technology that didn't require such a large oversize allowance.

Auto-Cle Socket Sets

We'll begin this section with a look at the early "Auto-Cle" socket sets, which served as Mossberg's introduction to pressed-steel socket technology.

The Auto-Cle socket sets were based on patents issued in 1904 and 1905 to Camille Contal, a French engineer. The earlier patent #751,055 was filed by Contal in 1903 and issued on February 2, 1904. (The date of this patent is sometimes marked incorrectly on tools.) The later patent was a re-issue of the original, issued as #RE12,379 on August 15, 1905.

The French origin of the design provides the "key" to understanding the name given to the sets. The socket sets were originally named Auto-Clé, with the word "clé" meaning "key" in French -- i.e. the key to your auto. Some early advertisements for the sets correctly included the accent mark, but later it was corrupted into the somewhat puzzling Auto-Cle name.

Before Mossberg acquired the rights to the Auto-Cle line, the sets were produced and marketed by the Quincy, Manchester, Sargent Company (Q.M.S.), a maker of hardware and tools located in New Jersey. It's currently an open question as to whether Mossberg served as the original contract manufacturer for the Q.M.S. company, possibly making the entire set, or at least the sockets. Auto-Cle sets are almost always found with Mossberg-marked sockets, and the other tools in the set were certainly well within Mossberg's manufacturing expertise. We're inclined to think that Mossberg was the maker of the sets all along, but will change this section as needed if new information is discovered.

After licensing the rights to the Auto-Cle line in 1908, Mossberg continued to supply the sets to Q.M.S. for some years. In late 1909 Q.M.S. established a subsidary division called the Motor Parts Company to handle all of their automotive specialties, and Auto-Cle sets sold after that time were marked with the Motor Parts name. Mossberg itself continued to sell the Auto-Cle sets for many years, and they were still listed in the catalogs at least into the early 1920s.

Mossberg "Auto-Cle" No. 1 Socket Set

Fig. 10. Mossberg "Auto-Cle" No. 1 Socket Set, ca. 1909-1912.

Fig. 10 shows an early Mossberg "Auto-Cle" No. 1 socket set, consisting of a ratchet, extension, universal, and sockets in a wooden case.

The hex sockets in the set cover the range from 5/16 to 1 inch by 32nds (23 sizes), plus four additional sizes 1-1/32, 1-3/32, 1-5/32, and 1-9/32, giving a total of 27 hex sockets. This particular selection of socket sizes became the de facto standard for "large" pressed-steel socket sets, and both Mossberg and other tool makers offered sets with these sizes for many years. (However, the rationale behind the selected sizes is a bit peculiar, as will be discussed at a later point.)

The set also includes three square sockets of sizes 13/32, 17/32, and 21/32, fitting square-head set screws of sizes 3/8, 1/2, and 5/8. In addition, the 17/32 square socket could be used as a connector for the 1/2-drive tools in the set.

This particular socket set was supplied to the Motor Parts division of the Q.M.S. company, as shown in the next figure.

Fig. 11. Detail for Cover of Auto-Cle No.1 Socket Set, ca. 1909-1912.

Fig. 11 shows the Motor Parts Company logo on the top cover of the socket set, with "Auto-Cle" inside an oval design resembling an old-fashioned keyhole. Within the oval are the markings "Motor Parts Co." and "Plainfield, N.J.", with "Reg. U.S. Pat. Off." below the oval. The markings are printed on (or possibly burned into) the wood cover, rather than being attached as a decal, as was commonly done for later Mossberg socket sets.

Mossberg 1/2-Drive Hex Sockets from "Auto-Cle" Socket Set

The Auto-Cle socket set was acquired with about a third of the sockets missing, but all of the remaining sockets (except one, possibly a later replacement) were marked with an older form of the Mossberg logo. This next figure shows some examples of the sockets.

Fig. 12. Mossberg 1/2-Drive Hex Sockets from "Auto-Cle" Socket Set, ca. 1909-1912.

Fig. 12 shows a group of three of the hex sockets from the Auto-Cle socket set, all stamped with the Mossberg M-Diamond logo on the base, with the fractional sizes stamped on a different side of the base. The sizes are, from left to right, 13/16, 27/32, and 7/8. (The selected sockets are the rightmost socket from the middle row and the left two sockets from the top row of the socket set photograph.)

Readers familiar with Mossberg sockets may notice the different style of marking on these sockets. The M-Diamond logo on the base is stamped with the diamond parallel to the axis of the socket, rather than in the transverse orientation found on later sockets. In addition, the logo is somewhat smaller, and the fractional size is stamped on a different side.

"Auto-Cle" 1/2-Drive Ratchet with Folding Handle

Fig. 13. Auto-Cle [Mossberg] 1/2-Drive Ratchet, with Inset for Marking Detail, ca. 1910-1915.

Fig. 13 shows an early 1/2-drive Mossberg "Auto-Cle" ratchet with a folding handle, stamped "Auto-Cle" and "Made in U.S.A." on the barrel (see inset). The markings also include "Reg. U.S. Pat. Off." with the patent dates "Feb. 5, 04" and "Aug. 15, 05".

The overall length is 9.6 inches, and the handle bar length is 6.5 inches. The finish is nickel plating.

The earlier patent date refers to patent #751,055, filed by Camille Contal in 1903 and issued on February 2 of 1904. (Note that the stamped date is incorrect.) The second patent date refers to the re-issue patent #RE12,379 issued in 1905.

This ratchet is shown included in the Auto-Cle socket set above, but was acquired separately from the set itself.

Mossberg 1/2-Drive 10 Inch Extension from "Auto-Cle" Socket Set

Although the Auto-Cle socket set wasn't advertised as "1/2 inch drive", all of the drive tools were in fact 1/2-drive and would even work with modern sockets. Early socket sets were generally regarded as self-contained tool collections, without regard to compatibility with other tools, but the fact that a very popular early set used 1/2 inch square drive must have helped establish that size as the common standard.

Fig. 14. Mossberg 1/2-Drive 10 Inch Extension, ca. 1909-1912.

Fig. 14 shows the Mossberg 10 inch extension from the Auto-Cle socket set, unmarked but believed to have been made by Mossberg.

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

The construction of the extension includes four stop tabs on each end, produced by a circular dimple on each side.

Mossberg Pressed-Steel Socket Sets

After getting its start with the "Auto-Cle" socket sets, Mossberg continued to develop and improve the pressed-steel socket technology. The introduction of the No. 350 ratchet in 1912 (patented in 1913) was a major improvement in ratchet technology. By 1912 Mossberg was offering an extensive selection of pressed-steel socket sets, with varying numbers of sockets and tools to fit every application and budget. Many of these sets became highly successful products and are still commonly found today, approaching 100 years later.

As the large number of socket sets can be confusing at times, we've added Table 3 below to summarize the various models. The socket set models were typically marked with a decal on either end of the box.

Table 3. Summary of Mossberg Standard Socket Set Models

Mossberg No. 6 Pressed-Steel Socket Set

This next figure shows an early Mossberg No. 6 pressed-steel socket set in a leather case.

Fig. 15. Mossberg Early Pressed-Steel Socket Set, ca. 1910-1915.

Fig. 15 shows an early Mossberg No. 6 socket set in a compact leather case, consisting of a No. 310 folding drive handle, seven hex sockets, and one spark-plug socket. Although the model number is not marked on the set, the set was identified by a listing in Mossberg catalog No. 12 from 1910, and the tools in this set match the description in the catalog.

The socket sizes are, from right to left in the bottom row, 17/32, 19/32, 21/32, 23/32, 13/16, and 29/32. The two sockets resting on the lid are a 1-3/32 standard socket at the left and a 29/32 spark-plug socket at the right. All of the sockets are marked with the M-Diamond logo, and the axis of the diamond is parallel to the socket axis, a detail noted in other early production.

The only drive tool in the set is a 1/2-drive No. 310 Folding Tee Handle shown in greater detail below. (The No. 310 model number is not marked on the tool, but was found in a catalog reference.)

Fig. 16. Top View of Mossberg No. 6 Socket Set, ca. 1910-1915.

Fig. 16 shows a top view of the early Mossberg socket set. The black leather case is embossed with the familiar M-Diamond logo on the top, and the cover is secured by two folding clasps on the front. The case is held together by rivets.

The dimensions of the case are approximately 6.5 inches long, 2.5 inches wide, and 2.0 inches tall.

Early [No. 310] 1/2-Drive Folding Tee Handle

Fig. 17. Mossberg No. 310 1/2-Drive Folding Tee Handle, ca. 1910-1915.

Fig. 17 shows the 1/2-drive Mossberg [No. 310] folding Tee handle from the early socket set above. The shank is stamped "Man'f'd by Frank Mossberg Co." and "Attleboro, Mass." with M-Diamond logos on either side, and with a "Pat'd. Feb. 15-10" patent date below. Although not marked with a model number, this tool was identifed as a No. 310 handle by a catalog reference.

The overall length is 6.0 inches folded and about 7.5 inches open. The finish is polished nickel plating.

The patent date refers to patent #949,083, filed by Frank Mossberg in 1909 and issued the following year.

In this early tool the drive stops are raised bosses in the center of the shank, rather than the pinched tabs used in later production.

[No. 310] 1/2-Drive Folding Offset Handle

The next figure shows another example of the No. 310 folding handle.

Fig. 18. Mossberg No. 310 1/2-Drive Folding Offset Handle, ca. 1910-1915.

Fig. 18 shows another somewhat later 1/2-drive Mossberg [No. 310] folding Tee handle, marked "Man'f'd by Frank Mossberg Co." and "Attleboro, Mass." with the M-Diamond logo, and with a "Pat'd. Feb. 15-10" patent date. As with the previous example, the model number is not marked and was identifed by a catalog reference.

The overall length is 6.0 inches folded, and the finish appears to be a thin dark lacquer.

The patent date refers to patent #949,083, filed by Frank Mossberg in 1909 and issued the following year.

This folding handle is very similar to the one shown in the previous figure, but with a few minor differences. The drive stops are pinched tabs at the corners, instead of the raised bosses in the center of the shank. Also, the finish is lacquer rather than the heavy nickel plating of the earlier example.

No. 7 Pressed-Steel Socket Set

The Mossberg No. 7 socket set was one of their more modest collections, consisting of two drive tools and 15 pressed-steel sockets in a wooden box. The drive tools are the No. 320 Ell handle and the No. 324 Tee handle; no ratchet was included in this set.

The socket sizes (all hex) are 13/32, 15/32, 17/32, 19/32, 5/8, 21/32, 23/32, 25/32, 13/16, 27/32, 29/32, 1 inch, 1-1/32, and 1-3/32. Also included is one 29/32 deep spark-plug socket.

Our set is currently being prepared for display.

No. 10 Pressed-Steel Socket Wrench Set

Fig. 20. Mossberg No. 10 Pressed-Steel Socket Set, ca. 1913-1923.

Fig. 20 shows an example of an early pressed-steel socket set, a Mossberg No. 10 socket set in a wooden box.

The original contents of the set were obtained from a 1922 catalog listing, and consisted of a ratchet, extension, universal, 19 standard hex sockets, two spark plug (deep) sockets, and an offset screwdriver. Our set as acquired is reasonably complete, but is missing the offset screwdriver and a few sockets, and at least one other socket is a later replacement.

The standard socket sizes (all hex) were 15/32, 1/2, 17/32, 19/32, 5/8, 21/32, 11/16, 23/32, 25/32, 13/16, 27/32, 7/8, 29/32, 31/32, 1 inch, 1-1/32, 1-3/32, 1-5/32, and 1-9/32. The set as pictured is missing the 15/32, 1/2, 27/32, and 1 inch sizes, and a 9/16 socket has been added.

The two spark plug sockets have sizes 29/32 and 1-5/32, and are shown in detail in the figures below.

Fig. 21 and Fig. 16 below show the decals glued to each end of the box, and it's fortunate that there are two, because both decals have suffered varying amounts of wear and damage over the years.

Fig. 21. First Decal from Mossberg No. 10 Socket Set.

Fig. 22. Second Decal from Mossberg No. 10 Socket Set.

Using both examples to fill in for the missing areas, the upper part of the decal reads "No. 10 Socket Wrench Set" with the M-Diamond logo (in red) in the center. The lower part reads "Made by Frank Mossberg Co." with "Attleboro, Mass. U.S.A." (partially missing) at the bottom.

No. 350 11/16-Drive Reversible Ratchet

Fig. 23. Mossberg No. 350 Ratchet, 1913+.

Fig. 23 shows the Mossberg No. 350 ratchet from the No. 10 set, marked "Frank Mossberg Co." and "Attleboro, Mass. U.S.A." with the M-Diamond logo.

The overall length is 10.0 inches, and the finish appears to be nickel plating.

The ratchet is also marked with the patent notice "Pat. Nov. 11, 1913", which refers to patent #1,078,059, issued to Frank Mossberg and assigned to the company.

The large opening of the ratchet (approximately 11/16) is sized to drive the sockets from the outside, and is fitted with a friction ball to help secure the socket. This 11/16 drive size was a standard for the early pressed-steel socket sets, and the sockets and drive tools from all makers were generally interchangeable. Since the sockets could also be driven by the 1/2 square inside opening, the sockets could be regarded as both 11/16-drive and 1/2-drive.

No. 351 11/16-Drive 9 Inch Extension

Fig. 24. Mossberg No. 351 11/16-Drive 9 Inch Extension.

Fig. 24 shows the Mossberg No. 351 9 inch extension included in the No. 10 set, marked "Frank Mossberg Co." and "Attleboro, Mass. U.S.A." with the M-Diamond logo.

The overall length is 9.4 inches, and the finish appears to be nickel plating.

The extension has a distinctive design that makes use of the inner and outer drive capabilities of the sockets. The large end of the extension is sized like the socket drive ends, and the other end terminates in a 1/2-drive stud with a friction ball. This design allows several different usage patterns.

One typical usage would be to drive the large end of the extension directly with the ratchet, with the male end driving a socket from the inside. A second usage pattern would be needed to connect the double-male universal joint with the extension. For this case, the universal joint would be inserted in the socket and the large end of the extension, and the ratchet would then drive the male stud of the extension using another socket as a shim.

No. 336 Double-Male Universal

Fig. 25. Mossberg No. 336 Double-Male Universal.

Fig. 25 shows the double-male universal from the No. 10 set, unmarked but identified as a Mossberg No. 336 in the catalogs.

The overall length is 3.8 inches, and the finish is nickel plating.

The male drive studs of the universal are 1/2 inch square, close enough to the industry standard to allow operation with modern sockets. The universal connects to the Mossberg sockets using the inside drive opening, and the connection to the No. 350 ratchet is made by inserting a spare socket as a shim.

402 29/32 Spark Plug Socket

Fig. 26. Mossberg 402 29/32 Spark Plug Socket, with Insets for Broach and Drive End.

Fig. 26 shows a Mossberg 402 29/32 spark plug socket, marked "Frank Mossberg Co." and "Attleboro, Mass. U.S.A." on one face, with the fractional size on another face.

The overall length is 3.5 inches, and the finish is plain steel.

The insets show the hex opening and square drive ends.

This socket was acquired as part of the Mossberg No. 10 Socket Set shown above.

422 1-5/32 Spark Plug Socket

Fig. 27. Mossberg 422 1-5/32 Spark Plug Socket.

Fig. 27 shows a similar Mossberg 422 1-5/32 spark plug socket, marked "Frank Mossberg Co." and "Attleboro, Mass. U.S.A." on one face, with the fractional size on another face.

The overall length is 3.9 inches, and the finish is plain steel.

This socket was acquired as part of the Mossberg No. 10 Socket Set shown above.

No. 11 Pressed-Steel Socket Set

The Mossberg No. 11 socket set included a No. 350 ratchet, No. 351 extension, 14 pressed-steel hex sockets, and one spark-plug socket.

The socket sizes (all hex) are 13/32, 15/32, 17/32, 19/32, 5/8, 21/32, 23/32, 25/32, 13/16, 27/32, 29/32, 31/32, 1-1/32, and 1-3/32. Also included is one 29/32 deep spark-plug socket.

Our set is currently being prepared for display.

No. 30 Pressed-Steel Socket Wrench Set

The next two figures illustrate the Mossberg No. 30 socket set, a compact collection intended for Ford owners.

Fig. 29. Mossberg No. 30 Socket Set, ca. 1915-1917.

Fig. 29 shows a Mossberg No. 30 socket set in a cloth-covered wooden box, consisting of a No. 355 ratchet handle, No. 336 universal, No. 351 extension, and eleven pressed-steel sockets of various types. The set is marked on the top cover with the embossed (not printed) text "Guaranteed Socket Wrench Set", followed by the M-Diamond logo and model number, with "Frank Mossberg Co." and "Attleboro, Mass. U.S.A." at the bottom.

The sockets in the bottom row begin at the left with a 19/32 square and a Ford special oval socket, followed by eight standard hex sockets with sizes 15/32, 17/32, 19/32, 21/32, 23/32, 25/32, 29/32, and 31/32. The set also includes a 31/32 deep spark plug socket. All of the sockets are marked with the Mossberg M-Diamond logo and fractional size, except that the special oval socket omits the size marking.

Fig. 30. Top View of Mossberg No. 30 Socket Set, with Inset for Marking Detail, ca. 1915-1917.

Fig. 30 shows a top view of the Mossberg No. 30 socket set, together with an inset showing the embossed marking on the ends of the set. Each end is marked with "No. 30 Socket Wrench Set" above the M-Diamond logo, with "Made By Frank Mossberg Co." and "Attleboro, Mass. U.S.A." at the bottom.

The dimensions of the box are 10.2 inches long by 3.3 inches wide by 2.8 inches high.

The ratchet in this set is marked with a patent pending notation (see figure below), suggesting that this set was among the earlier production of this model. The earliest known commercial reference to the No. 30 set is in a 1917 issue of The Fordowner, leading to an estimated production date of 1915-1917 for this set.

The No. 30 socket set was similar to Mossberg's earlier No. 15 (or 15A) sets, but included a non-reversible ratchet for slightly lower cost.

No. 355 11/16-Drive (Non-Reversible) Ratchets

Fig. 31. Mossberg No. 355 Ratchet, ca. 1915-1916.

Fig. 31 shows the Mossberg No. 355 non-reversible ratchet from the No. 30 set, stamped "Frank Mossberg Co." and "Attleboro, Mass. U.S.A." with the M-Diamond logo, and with a "Pat. Pend." notice.

The overall length is 8.6 inches, and the finish is black paint.

The No. 355 ratchet is similar to the well-known Mossberg No. 350 Ratchet, but is slightly shorter and does not have a reversing mechanism.

The patent corresponding to the pending status is probably patent #1,165,995, filed in 1915 and issued late in that year. This patent describes the construction of a simple and inexpensive ratchet and is best known for its use with the Mossberg 645 Ford Reverse and Brake Ratchet.

The identification of the patent for the No. 355 model is somewhat uncertain, as no examples of this ratchet are known to have a patent date marking. However, since the No. 355 ratchet was intended as a lower-cost model, and the ratchet is known to have been offered as early as 1916, the #1,165,995 patent seems to be the likely choice.

Fig. 32. Mossberg No. 355 Ratchet, with Inset for Side View.

Fig. 32 shows a later example of the Mossberg No. 355 ratchet, stamped "Manf'd By Frank Mossberg Co." and "Attleboro, Mass. U.S.A." with the M-Diamond logo.

The overall length is 8.6 inches, and the finish is nickel plating.

The ratchet mechanism uses a 21-tooth drive gear with an 11/16 square opening. The opening is fitted with a detent ball to help hold the socket, visible on the top wall in the photograph.

[No. 351] 11/16-Drive 9 Inch Extension from No. 30 Set

Fig. 33. Mossberg [No. 351] 11/16-Drive 9 Inch Extension from No. 30 Set, ca. 1915-1917.

Fig. 33 shows the 11/16-drive 9 inch extension from the No. 30 set, unmarked but identified as No. 351 in the catalogs.

The overall length is 9.4 inches, and the finish is black paint.

This extension is very similar to the Mossberg No. 351 Extension in an earlier figure, but is unmarked and has a painted finish instead of nickel plating.

Pressed-Steel Hex Sockets from No. 30 Set

Fig. 34. Mossberg Pressed-Steel Sockets from No. 30 Set, with Inset for Marking Detail, ca. 1915-1917.

Fig. 34 shows the five largest hex sockets from the Mossberg No. 30 set, each stamped with the fractional size and the M-Diamond logo. The socket sizes are, from the left, 21/32, 23/32, 25/32, 29/32, and 31/32.

The finish is black paint.

The inset at the top shows the M-Diamond logo stamped on the base of each socket. Note that the axis of the logo is perpendicular to the axis of the socket, a detail found on later Mossberg production.

General Service and Automotive Specialty Tools

Open-End Wrenches

Mossberg began offering open-end wrenches as early as 1910, with seven models listed in the catalog No. 12 from that year. The wrenches were offered under the title "Mossberg Double End Angle Wrenches", with sizes and models 1/4x5/16 (210), 3/8x7/16 (220), 1/2x9/16 (230), 5/8x3/4 (240), 7/8x1 (250), 1x1-1/16 (260), and 1-1/8x1-1/4 (270).

In later years the selection of sizes was increased substantially, and the model numbers were reworked to keep the standard double-open wrenches in the 2xx model series. For example, the 7/8x1 size was initially model number 250, but later became model number 275.

Mossberg open-end wrenches were constructed of stamped steel, then hardened and tempered. The 1910 catalog offered two finish options, semi-finished and polished nickel.

210 1/4x5/16 Open-End Wrench

Fig. 35. Mossberg No. 210 1/4x5/16 Open-End Wrench.

Fig. 35 at the left shows a Mossberg No. 210 1/4x5/16 open-end wrench of stamped steel construction, marked with the M-Diamond logo.

The overall length is 3.2 inches, and the finish is plain steel.

232 7/16x1/2 Open-End Wrench

Fig. 36. Mossberg No. 232 7/16x1/2 Open-End Wrench.

Fig. 36 at the left shows a Mossberg No. 232 7/16x1/2 open-end wrench of stamped steel construction, marked with the M-Diamond logo.

The overall length is 4.9 inches, and the finish is plain steel.

234 1/2x19/32 Open-End Wrench

Fig. 37. Mossberg No. 234 1/2x19/32 Open-End Wrench.

Fig. 37 shows a Mossberg No. 234 1/2x19/32 open-end wrench of stamped steel construction, marked with the M-Diamond logo.

The overall length is 4.9 inches, and the finish is plain steel.

240 1/2x5/8 Open-End Wrench

Fig. 38. Mossberg No. 240 1/2x5/8 Open-End Wrench.

Fig. 38 shows a Mossberg No. 240 1/2x5/8 open-end wrench of stamped steel construction, marked "M'f'd by Frank Mossberg Co." and Attleboro, Mass. U.S.A." with M-Diamond logos on either side of the model number.

The overall length is 5.8 inches, and the finish is plain steel.

253 5/8x3/4 Open-End Wrenches

The next two figures show examples of the Mossberg No. 253 wrench model.

Fig. 39. Mossberg No. 253 5/8x3/4 Open-End Wrench, with Inset for Side View.

Fig. 39 shows a Mossberg No. 253 5/8x3/4 open-end wrench of stamped steel construction, marked with M-Diamond logos on either side of the model number.

The overall length is 6.9 inches, and the finish is polished steel.

This wrench is more finely finished than was typical for the Mossberg stamped wrenches. The edges have been ground to a slightly convex contour (see top inset), and the faces of the wrench have been polished.

Fig. 40. Mossberg No. 253 5/8x3/4 Open-End Wrench.

Fig. 40 shows a Mossberg No. 253 5/8x3/4 open-end wrench of stamped steel construction, marked with M-Diamond logos on either side of the model number.

The overall length is 6.9 inches, and the finish is plain steel.

260-A 5/8x15/16 Open-End Wrench

Fig. 41. Mossberg No. 260-A 5/8x15/16 Open-End Wrench.

Fig. 41 shows a Mossberg No. 260-A 5/8x15/16 open-end wrench of stamped steel construction, marked with the M-Diamond logo.

The overall length is 7.8 inches, and the finish is plain steel.

275 7/8x1 Open-End Wrench

Fig. 42. Mossberg No. 275 7/8x1 Open-End Wrench.

Fig. 42 shows a Mossberg No. 275 7/8x1 open-end wrench of stamped steel construction, marked with the M-Diamond logo.

The overall length is 8.7 inches, and the finish is plain steel.

715B 1/2x11/16 Open-End Wrench

Fig. 43. Mossberg No. 715B 1/2x11/16 Open-End Wrench.

Fig. 43 shows a Mossberg No. 715B 1/2x11/16 open-end wrench of stamped steel construction, marked "Made in U.S.A." with the M-Diamond logo.

The overall length is 5.9 inches, and the finish is plain steel.

1235 1/2x9/16 S-Shaped Open-End Wrench

Fig. 44. Mossberg No. 1235 1/2x9/16 S-Shaped Open-End Wrench.

Fig. 44 at the left shows a Mossberg No. 1235 1/2x9/16 S-shaped wrench of stamped steel construction, marked with the M-Diamond logo.

The overall length is 4.9 inches, and the finish is plain steel.

551 25/32 Single Open-End Wrench

Fig. 45. Mossberg 551 25/32 Single Open-End Wrench.

Fig. 45 shows a Mossberg 551 25/32 open-end wrench of stamped steel construction, marked with the M-Diamond logo.

The overall length is 6.4 inches, and the finish is plain steel.

470 Alligator Wrench

Fig. 46. Mossberg 470 Alligator Wrench.

Fig. 46 shows a Mossberg 470 alligator wrench of stamped steel construction, stamped with two M-Diamond logos.

The overall length is 6.0 inches, and the finish is polished steel, with minor pitting due to rust.

Fixed Socket Wrenches

Early 17/32x21/32 Z-Shaped Double Socket Wrench

Fig. 47. Mossberg 17/32x21/32 Z-Shaped Double Socket Wrench, with Insets for Socket Detail, ca. 1910-1918.

Fig. 47 shows a Mossberg 17/32x21/32 double socket wrench with a Z-shaped handle, marked with the M-Diamond logo on the shank and sockets.

The overall length is 8.5 inches, and the finish is plain steel.

As can be seen from the photograph, this wrench was constructed by crimping two pressed-steel sockets to a bent steel handle.

This wrench was one of the tools included in the Mossberg No. 17 wrench kit for the Ford Model T, a set of five fixed socket wrenches in a canvas roll. The No. 17 set is listed for $2.00 in a 1916 Central Automobile Supply catalog.

Early 23/32x25/32 Z-Shaped Double Socket Wrench

Fig. 48. Mossberg 23/32x25/32 Z-Shaped Double Socket Wrench, with Insets for Socket Detail, ca. 1910-1918.

Fig. 48 shows another example of the Z-shaped wrenches, a Mossberg 23/32x25/32 double socket wrench of pressed-steel construction, marked with the M-Diamond logo on the shank and sockets.

The overall length is 8.7 inches, and the finish is plain steel.

The 23/32 and 25/32 socket openings on this wrench were intended for servicing 11/16 and 3/4 nut sizes, respectively, as pressed-steel sockets were always specified 1/32 oversize. This wrench was one of the tools included in the Mossberg No. 17 wrench kit for the Ford Model T, a set of five fixed socket wrenches in a canvas roll. The No. 17 set was offered with a list price of $2.00 in the 1916 Central Automobile Supply catalog.

Early 19/32x19/32 Z-Shaped Double Socket Wrench

Fig. 49. Mossberg 19/32x19/32 Z-Shaped Double Socket Wrench, with Insets for Socket Detail, ca. 1916-1918.

Fig. 49 shows another example of the Mossberg Z-shaped wrenches, a double socket wrench with 19/32 sockets of square and oval cross-section, stamped with the M-Diamond logo on the shank.

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

This wrench was intended for servicing the Model T main bearings, which used oval-shaped nuts on earlier models and square nuts after around 1916.

This wrench was one of the tools included in the Mossberg No. 17 wrench kit for the Ford Model T, a set of five fixed socket wrenches in a canvas roll.

Mossberg 623 Socket Wrench

Fig. 50. Mossberg 623 5/8 Socket Wrench, with Inset for Detail.

Fig. 50 shows a Mossberg 623 6-point 5/8 socket wrench with an offset curled-bar handle. The wrench is marked "Frank Mossberg Co." and "Attleboro, Mass. U.S.A.", with "Made in U.S.A." and the M-Diamond logo. The overall length is 10.4 inches.

The finish is a heavy nickel plating. The offset handle was designed for clearance in connecting-rod applications.

Mossberg 2149 Socket Wrench

Fig. 51. Mossberg 2149 3/4 Offset Socket Wrench, with Inset for Construction Detail.

Fig. 51 shows a Mossberg 2149 offset socket wrench with a 3/4 hex opening, stamped "Mossberg Corp." and "Attleboro, Mass. U.S.A." with the M-Diamond logo.

The overall length is 10.0 inches, and the finish is a heavy nickel plating.

The inset shows the hex opening forged into the handle.

Mossberg 630 Triple-Socket Wrench

Fig. 52. Mossberg 630 (9/16x11/16)x5/8 Triple Socket Wrench, with Inset for Detail.

Fig. 52 shows a Mossberg 630 triple-socket wrench with (measured) sizes (9/16x11/16)x5/8, marked with the M-Diamond logo.

The overall length is 10.3 inches.

Specialty Tools

645 Ford Reverse and Brake Ratchet Wrench

Fig. 53. Mossberg 645 11/16 Ratcheting Box Wrench, with Inset for Side View.

Fig. 53 shows a Mossberg 645 11/16 ratcheting box wrench intended for servicing Model T reverse and brake bands. The handle is stamped "Frank Mossberg Co." and "Attleboro, Mass. U.S.A." with the M-Diamond logo, and the application is noted as "For Ford Reverse & Brake Pedal Bands".

The overall length is 6.0 inches, and the finish is plain steel.

The wrench is also marked with a "Pat. Dec. 28, 1915" patent notice, which corresponds to patent #1,165,995. The patent describes the construction of a simple and inexpensive ratchet, as needed for the high-volume but cost sensitive Model T tools market.

No. 654 Valve Spring Lifter

Fig. 54. Mossberg No. 654 Valve Spring Lifter, with Inset for Top View, ca. 1914-1920.

Fig. 54 shows an early Mossberg No. 654 valve spring lifter, stamped "Frank Mossberg Co." and "Attleboro, Mass. U.S.A." with the M-Diamond logo, and with a "Pat. Jul. 28, 14" patent notice.

The overall length is 7.1 inches, and the finish is nickel plating.

The patent date corresponds to patent #1,105,096, filed by S.C. North in 1912 and issued in 1914.

Mossberg 624 Ratcheting Socket Wrench

Our next figure shows the fancy version of a connecting-rod wrench, with a built-in ratchet for more convenient operation.

Fig. 55. Mossberg 624 5/8 Ratcheting Socket Wrench, with Inset for Top View.

Fig. 55 shows a Mossberg 624 5/8 ratcheting socket wrench, marked "Frank Mossberg Co." and "Attleboro, Mass. U.S.A." with the M-Diamond logo. The overall length is 10.6 inches, and the finish shows some traces of the original nickel plating.

The ratchet mechanism is similar to that used on older bit braces, with dual pawls alternately deactivated by a rotating ring. The selector ring actually has three modes of operation, with one position leaving both pawls engaged so that the socket is locked in place.

Mossberg 631 Ratcheting Socket Wrench

Fig. 56. Mossberg 631 19/32x5/8 Ratcheting Double-Socket Wrench, with Inset for Side View.

Fig. 56 shows a rare Mossberg 631 double-socket ratcheting wrench, marked "Made in U.S.A." with the M-Diamond logo. The socket sizes were measured as 19/32 and 5/8 (or possibly 21/32).

The overall length is 9.8 inches, and the finish is polished nickel plating.

The ratchet action can be reversed by using the rod extending from the handle. The rod is first pulled out slightly, and then turned to reverse the ratchet direction. Although the ratchet mechanism is fairly coarse with only 7 teeth, it still offers greater convenience than a fixed socket wrench.

The dual socket unit is held in place by a spring circlip, suggesting that the tool may have had interchangeable socket sizes available. (No catalog reference has been found yet for this model.)