Later Developments

The year 1919 was an eventful year for the Frank Mossberg Company, as the founder Frank Mossberg sold a controlling interest in the company, intending to devote more time to other ventures. Walter I. Tuttle became the new company president; Tuttle had previously worked as an engineer for the Frank Mossberg Company and had developed a number of patents.

An important external event was the founding of Blackhawk Manufacturing as a division of the American Grinder Company. By mid 1919 Blackhawk was offering an extensive line of 1/2-drive socket sets featuring heavy-duty machined and broached sockets with a variety of drive tools. The enthusiastic reception given to these new sets by the automotive trades effectively marked the end of the pressed-steel socket era, although it would be a few years yet before this was universally recognized.

The entry of Blackhawk into the automotive service tools business had a huge impact on Walden-Worcester, at that time the leading maker of fixed socket wrenches. In addition to offering heavy-duty interchangeable socket sets, Blackhawk also copied Walden's full line of fixed socket wrenches customized for service jobs on every make of automobile. More information can be found in our article on Walden under Heavy-Duty Interchangeable Sockets.

A Near Miss for Mossberg

Although the sudden new competition from Blackhawk had a more immediate effect on Walden-Worcester, the Frank Mossberg Company, Walden's arch-competitor, was also greatly impacted. Within a decade, Mossberg's market-leading pressed-steel socket business would wither into nothing, leaving a weakened shell of a company that would never regain a leading position.

But in Mossberg's case, the loss of its once valuable franchise is probably best regarded as a self-inflicted injury. We can offer evidence that Mossberg understood beforehand that changes were coming to the socket industry, but then failed to take effective action.

In early 1919 Mossberg began advertising a No. 45 socket set, described in their catalogs as a "'Heavy Duty' Socket Speed Brace Wrench Set". The sockets in the set were made by a process somewhat similar to that for pressed-steel sockets, but used heavier gauge steel and so had some claim to the heavy-duty title. The set consisted of just one drive tool, a 1/2-drive speeder, along with 15 sockets and a universal. The new sockets were designed for 1/2 square internal drive only, unlike the internal/external mixed drive used for Mossberg pressed-set sets.

The Mossberg No. 45 set turned out to be a commercial failure, but the existence of the set and the reasons for its failure provide valuable insights into the company. The proximate causes for the lack of commercial success can be summarized as (1) a lack of depth in the heavy-duty line, and (2) the failure of the company's advertising to distinguish the heavy-duty set from Mossberg's existing line.

To expand on the points in the previous paragraph, we note that initially the new heavy-duty sockets were available only in the No. 45 set, and that the set included only a speeder as a drive tool. Since speeders are not high-leverage drive tools, purchasers of the set might not have even noticed that the new sockets were significantly stronger than the older pressed-steel variety.

If Mossberg had included new drive tools to go with the sockets -- perhaps a version of the Mossberg 350 Ratchet with a 1/2-drive stud, a stronger version of the Mossberg 320 Offset Handle, and a sliding Tee handle with a 10 inch bar -- the introduction of the "Heavy Duty" line might have been much more favorable.

What happened here is that the Frank Mossberg Company fell under the curse identified in The Innovator's Dilemma by Clayton M. Christensen (HarperBusiness 2000), whereby leading companies sometimes fail to respond appropriately to disruptive technology. As the leading maker of pressed-steel socket sets, Mossberg recognized that changes were coming to the industry, but attempted to slow or deflect the flow of progress in order to protect its cash-cow businesses, pressed-steel socket sets and to a lesser degree fixed-socket wrenches.

Mossberg did offer some new products that could have extended its relevance to the industry, but promoted them only half-heartedly, allowing other companies to dominate the next phase of the socket industry. In the next sections we'll look at two of the half-way products Mossberg offered to shore up its product line.

Heavy-Duty "Indestructible" Sockets

By 1919 Mossberg had developed a new line of heavy-wall sockets, pressed from much heavier steel than that used for the older pressed-steel sockets, and designed to be driven from the inside as 1/2-drive sockets. Mossberg called the new sockets "Indestructible", and these new sockets were combined with a speeder handle to form the No. 45 socket set.

Significantly, the same heavy-wall sockets were also used for Mossberg's fixed socket wrenches.

The development of these heavy-wall sockets shows that Mossberg had realized that the older pressed-steel sockets were not strong enough for the increasing demands of automobile and truck service. If the new sockets had been offered with a full line of comparable drive tools, they could have been an important product in the development of socket tools. However, the limited capabilities of the No. 45 set, with just a speeder as the drive tool, made it at best only a modestly successful commercial product.

The "Indestructible" sockets were made for only a short period, as by 1923 they were no longer listed in the Mossberg catalog.

Mossberg No. 45 "Indestructible" Socket Set

Fig. 107A. 1919 Catalog Illustration of Mossberg No. 45 Socket Set.

The scan in Fig. 107A shows the Mossberg No. 45 set as it appeared on page 46 of their 1919 catalog. The set consisted of a No. 359 speed brace, a No. 336 double-male universal, a No. 167 connector socket, and 15 "Indestructible" sockets ranging from 7/8 to 1-1/2 inches.

The caption in the illustration notes the "Interchangeable Heavy-Duty Indestructible Sockets", showing that Mossberg was clearly trying to address the markets for which pressed-steel sockets were too weak.

Note though that the limited range of socket sizes, with nothing smaller than 7/8 inch, makes it clear that this set was intended as a niche product only. The target customer was apparently someone who intended to buy a number of speeder socket wrenches, and by purchasing this set gained the advantage of a compact set with interchangeable sockets.

We have an example of the No. 45 socket set and are currently preparing it for display.

Mossberg No. 360 1/2-Drive Short Speeder Handle

Fig. 108. Mossberg No. 360 1/2-Drive Short Speeder Handle, with Inset for Detail, ca. 1918-1920.

Fig. 108 shows a 1/2-drive Mossberg No. 360 short speed handle or brace, marked "Made in U.S.A." with the M-Diamond logo.

The overall length is 11.5 inches.

The drive end has a detent ball and four pinched tabs as stops, typical construction for early tools of this type.

The circular end cap is marked "Patent Pending", and a similar but later Mossberg tool showed the patent date to be March 20 of 1920.

A search of the patent records found the corresponding patent to be #1,335,408, titled "Brace Construction" and issued to W.I. Tuttle. Based on the filing date of October 3 in 1918, this particular tool was likely made between 1918-1920.

This was the type of speeder (though not the exact model) included in the No. 45 socket set of 1919.

Mossberg "Indestructible" Sockets

The next figure shows examples of the new style of heavy-wall "Indestructible" sockets used in the No. 45 socket set.

Fig. 109. Mossberg Heavy-Wall "Indestructible" Sockets, with Inset for Interior, ca. 1919-1922.

Fig. 109 shows two Mossberg sockets made with a new style of heavy-wall construction, marked "Made in U.S.A." with the M-Diamond logo.

The fractional sizes are marked but a bit difficult to read. The left hand socket marking appears to be 1-1/64 and measures 1.016 inches, and the right hand socket is apparently 1-9/64 and measures 1.140 inches.

Note that the intended service size for these sockets would have been 1 inch and 1-1/8 respectively. Mossberg had been able to improved the size tolerance for the dies used in making these sockets, and as a result the oversize allowance had been reduced to 1/64. (Recall that the pressed-steel sockets were specified as 1/32 oversize.) It's unfortunate that Mossberg chose to mark these in 64th fractions, instead of marking the nominal size and burying the small oversize allowance.

Although the sockets are constructed with a square base resembling the pressed-steel sockets, these sockets were designed to be driven by the 1/2-square inner opening. Note that a hole has been drilled in the side to help secure the socket with a friction ball, or to secure the socket with a pin if used to make a fixed socket wrench.

Note the striations along the walls of the sockets in the photograph. These marks provide a clue about the production process, as sheet steel was forced into a cylindrical die using a hexagonal mandrel. Mossberg's production process was probably fairly similar to the cold-forming technology that became the dominant method of socket production by the 1970s.

Mossberg No. 363 3/4 Speeder Socket Wrench

This next figure shows an example of how Mossberg incorporated its "Indestructible" sockets into the production of fixed-socket speeder wrenches.

Fig. 110. Mossberg No. 363 3/4 Speeder Socket Wrench, with Insets for Socket and Marking Detail.

Fig. 110 shows a Mossberg No. 363 3/4 speeder socket wrench, marked "Made in U.S.A." with the M-Diamond logo. The socket is marked 49/64, the actual size when the 1/64 oversize allowance is added. (Earlier pressed-steel sockets required a 1/32 oversize allowance.)

The speeder has a throw of 4.2 inches and an overall length of 13.0 inches, and the finish is nickel plating.

This speeder wrench is basically a standard 1/2-drive short brace with a permanently attached "Indestructible" socket. The rotating hand grip and end piece are made of seamless tubing, swaged to the shank diameter, and the hand grip is held in place by two pins (not shown in photograph).

The left inset provides a close-up of the socket attachment, showing a standard "Indestructible" socket attached with a pin to the square-drive speeder. The socket is marked "Made in U.S.A." with the fractional size (49/64) and the M-Diamond logo, the standard markings for Mossberg sockets.

Mossberg No. 366 1/2-Drive 14 Inch Speeder

Fig. 111. Mossberg No. 366 1/2-Drive 14 Inch Speeder, with Insets for Marking Detail, ca. 1920s.

Fig. 111 shows a 1/2-drive Mossberg No. 366 14 inch speeder (or brace), stamped "Frank Mossberg Corp." and "Attleboro, Mass. U.S.A." with the M-Diamond logo on the shank.

The tool is also marked with "Frank Mossberg Co." and "Attleboro, Mass. U.S.A." stamped on the rotating grip and end-piece.

The overall length is 13.9 inches, and the throw is 5.2 inches.

The rotating end piece is constructed from rolled sheet metal held in place with crimped end caps. Although not marked with a patent notice, the handle construction is covered by patent #1,438,970, issued to W. Tuttle in 1922.

Rotating hand grips of this type are characteristic of Mossberg's construction in the 1920s.

Mossberg No. 367 1/2-Drive 20 Inch Speeder

Fig. 112. Mossberg No. 367 1/2-Drive 20 Inch Speeder, with Insets for Marking Detail, ca. 1920s.

Fig. 112 shows a 1/2-drive Mossberg No. 367 20 inch speeder, marked "Frank Mossberg Corp." and "Attleboro, Mass. U.S.A." with the M-Diamond logo.

The speeder has a throw of 4.2 inches and an overall length of 19.6 inches.

The rotating end piece is constructed from rolled sheet metal held in place with crimped end caps. Although not noted on this tool, the handle construction is covered by patent #1,438,970, issued to W. Tuttle in 1922.

Rotating hand grips of this type are characteristic of Mossberg's construction in the 1920s.

"Ever-Wear" Male Drive Sockets

By around 1922 Mossberg had introduced a new style of male-drive sockets under the "Ever-Wear" brand. The sockets were forged from a slug of chrome-manganese alloy steel and then machined on one end to form an approximately 11/16 square drive stud, a size designed to fit the standard Mossberg ratchets used for pressed-steel sockets.

The "Ever-Wear" sockets are significant as one of the earliest sockets produced from alloy steel, but their non-standard male drive kept them from becoming popular except among existing Mossberg customers. [Recently found information (2021) indicates that the Abegg & Reinhold "Varco" line offered nickel alloy steel sockets in 1920.]

Although the "Ever-Wear" sockets already fit the older No. 350 ratchet by design, providing other drive tools meant that Mossberg had to design a suite of special tools with 11/16 female receptacles. These included a longer No. 356 ratchet, a No. 341 Tee handle and extension, a No. 352 Ell handle, Nos. 353 and 354 braces, and a No. 339 universal.

The apparent reason for the creation of the "Ever-Wear" sockets was that Mossberg had begun making its speeder wrenches with an alloy-steel socket permanently joined. According to 1924 catalog, these wrenches were made by upsetting and forging a socket on the end of piece of chrome-manganese steel rod, so that the entire unit was made of alloy steel. (Blackhawk had started offering fixed-socket wrenches with welded sockets in late 1920.)

Since Mossberg would have needed production equipment for forging the alloy-steel sockets, creating the "Ever-Wear" socket line may have been an afterthought.

If Mossberg had chosen to make "Ever-Wear" as 1/2-female-drive sockets to be used with 1/2-drive interchangeable handles, Mossberg could have been one of the first manufacturers to offer alloy sockets in the industry standard configuration, and this might have given the company a significant share of the rapidly growing market for socket tools.

Instead, the "Ever-Wear" line must be seen as another wasteful diversion from a company unwilling to cannibalize the sales of its pressed-steel socket business, in keeping with our earlier comments on the The Innovator's Dilemma.

Mossberg No. 65 "Ever-Wear" Socket Set

Fig. 113A. 1924 Catalog Listing of Mossberg No. 65 "Ever-Wear" Socket Set.

The scan in Fig. 113A shows a catalog listing for the Mossberg No. 65 "Ever-Wear" socket set, consisting of a No. 356 ratchet, No. 341 Tee handle, No. 339 universal, 10 "Ever-Wear" sockets in sizes from 7/16 to 7/8, and two spark-plug sockets.

We were fortunate to acquire a rare Mossberg No. 65 "Ever-Wear" socket set in its original wooden box. Although not complete, the set has most of the specified components.

The set is currently being prepared for display.

"Ever-Wear" Sockets

Fig. 114. Mossberg "Ever-Wear" Male Drive Sockets, with Insets for Broaching and Marking Detail, ca. 1922-1925.

Fig. 114 shows several examples of the Mossberg "Ever-Wear" male drive sockets, each stamped on the base with the M-Diamond logo and fractional size.

The sizes are, from the left, 7/16 square, 7/16 hex, 11/16 hex, and 31/32 hex.

"Ever-Wear" 5/8 Socket

Fig. 115. Mossberg "Ever-Wear" 5/8 Socket, with Insets for Broaching and Marking Detail, ca. 1922-1925.

Fig. 115 shows a Mossberg "Ever-Wear" 5/8 socket, stamped on the base with the fractional size and two M-Diamond logos.

The finish is plain steel.

Later Pressed-Steel Socket Sets

Mossberg continued to produce pressed-steel socket sets throughout the 1920s, although the number and variety of the models gradually declined as sales tapered off. During this period the sets didn't change much, but one notable change was the switch from wooden cases to metal boxes, which occurred during the mid 1920s.

Another notable change appears in the context of the Mossberg sets sold by Sears Roebuck. Sears had long been a customer for Mossberg (possibly their biggest reseller) and offered a number of Mossberg products, including socket sets No. 6, No. 14, and No. 15, plus a slightly modified version of the Auto-Clé No. 1 set called the "Aristocrat No. 1" by Sears.

The Auto-Clé sets sold by Sears usually substituted a No. 350 ratchet for the tubular ratchet, but in 1922 a Sears Justice Tires catalog illustrated the Aristocrat No. 1 Socket Set with a forged-body ratchet, immediately recognizable as the "W.&M. Co." mystery ratchet shown in the next figure.

"W. & M. Co." Mystery Ratchet

Fig. 116. W. & M. Co. Female-Drive Ratchet, with Inset for Side View, ca. Early to Mid 1920s.

Fig. 116 shows an example of the mysterious "W. & M. Co." female-drive ratchet, marked only with "W. & M. Co." forged into the shank.

The overall length is 9.0 inches.

The square drive opening is the correct size for the standard pressed-steel sockets made by Mossberg, Walden, and others.

This ratchet model has been seen frequently in sets of pressed-steel sockets, sometimes with unmarked sockets or sockets from several makers. Although the ratchet is clearly marked, no information has yet been found for the identity of the "W. & M." company.

An important clue to the origin is provided by the 1922 patent #1,426,127, filed by W.I. Tuttle in 1920 and issued in 1922, with assignment to the Frank Mossberg Company. The patent illustration matches this ratchet almost exactly, and the construction details (such as the detent ball in the opening) also match this example.

With the discovery of the Sears catalog listing showing this ratchet in the Aristocrat No. 1 Socket Set, we are now confident that the ratchet was produced by Mossberg for its Sears production. However, the meaning or reason for the "W. & M. Co." marking remains unknown.

Alloy Steel Socket Sets

Fig. 117A. 1928 Notice for Apco-Mossberg Socket Sets.

By around 1925 Mossberg had finally accepted the emerging industry standards and began producing 1/2-drive socket sets with sockets made of chrome-molybdenum steel.

The socket sets included Nos. 81 and 82 for professional use, Nos. 80 and 84 for automobile owners, plus an inexpensive No. 83 "Han-D-Set" made with cheaper steel.

The scan in Fig. 117A shows several Apco-Mossberg socket sets (along with Bonney "C-V" wrench sets), as published on page 85 [External Link] of the January, 1928 edition of Motor Record.

The upper left shows a No. 800 display cabinet intended for dealers, and the lower left illustration shows the Apco-Mossberg No. 82 set.

In later years Mossberg also offered socket tools in larger drive sizes, including 7/8 square drive, a size also offered by Blackhawk and Snap-on.

By 1929 Mossberg had completely redesigned its socket tools in an attempt to appeal to professional mechanics. The new tools were given a 900 series of model numbers and resembled the models available from Blackhawk and Snap-on at the time, with rotating knurled hand grips on many of the drive tools. The Nos. 80 to 84 socket sets were discontinued and replaced by a 900 A.B.C. set, which could be ordered in three separate parts (or complete), depending on the needs of the customer.

At this time the company also divided its tools into two separate catalogs, a "Mossberg Line" catalog for the new professional tools, and a "Mossberg Wrenches" catalog for the older line of Model T tools and pressed-steel socket sets. This revamping of the product line in 1929 was significant, as it shows that Mossberg had realized that the company's long association with pressed-steel socket sets was now hindering its attempts to compete in the market for professional tools.

Although the Mossberg alloy-steel socket sets were very well made, the sales volumes appear to have been quite low, as these sets are fairly rare. The delay in producing industry standard sets meant that the Mossberg company made a late entry into a highly competetive market, and the company never gained a significant market share in this second-generation socket technology.

Mossberg No. 80 1/2-Drive Socket Set

Fig. 117B. 1928 Catalog Listing of Mossberg No. 80 Socket Set.

The Mossberg No. 80 1/2-drive socket set was a compact set in a metal box intended for automobile owners. The set consisted of a No. 350 reversible ratchet, a No. 371 drive adapter, No. 372 and No. 373 extensions, and 10 chrome-molybdenum sockets ranging from 7/16 to 7/8.

The scan in Fig. 117B, from page 564 of the 1928 McMaster-Carr catalog, provides an illustration of the No. 80 set and lists the contents, noting that the sockets are made of chrome-molybdenum steel. The set was available for a $5.60 net price.

We are fortunate to have an example of this somewhat rare set. Our No. 80 set was acquired complete and in very good condition, and also included a Mossberg No. 370 1/2-drive sliding Tee handle added by the previous owner.

Fig. 118A. Mossberg No. 80 1/2-Drive Socket Set, ca. 1927-1928.

Fig. 118A shows a rare Mossberg No. 80 1/2-drive socket set in its metal box, consisting of a [No. 350] reversible ratchet, a No. 371 drive adapter, a No. 372 5 inch extension, a No. 373 10 inch extension, and 10 chrome-molybdenum sockets ranging from 7/16 to 7/8.

The decal on the inside of the lid shows "No. 80 Socket Wrench Set", followed by the M-Diamond logo and "Made by Frank Mossberg Co.", with "Attleboro, Mass. U.S.A." at the bottom.

The socket sizes are, from the left, 7/16, 1/2, 9/16, 19/32, 5/8, 11/16, 3/4, 25/32, 13/16, and 7/8. The sockets are marked with the fractional size flanked by M-Diamond logos, but without a model number.

The tools and sockets have a nickel plated finish, except for the ratchet, which has a cadmium finish.

Fig. 118B. Top Cover of Mossberg No. 80 1/2-Drive Socket Set, ca. 1927-1928.

Fig. 118B shows the top cover of the Mossberg No. 80 set, with a badly scratched decal reading "Mossberg" and "Socket Wrench Set".

The dimensions of the box are 10.5 inches long by 3.3 inches deep by 1.7 inches high.

APCO-Mossberg [No. 350] 1/2-Drive 10 Inch Ratchet with No. 371 Drive Adapter

Fig. 119. APCO-Mossberg No. 350 1/2-Drive 10 Inch Ratchet, with Insets for Side View and Marking Detail, ca. 1927-1928.

Fig. 119 shows the 1/2-drive APCO-Mossberg [No. 350] 10 inch ratchet and No. 371 drive adapter from the No. 80 set.

The ratchet is stamped "APCO Mossberg" and "Attleboro, Mass. U.S.A." near the drive gear, as seen in the middle inset. The drive adapter is stamped with the M-Diamond logo and model number.

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

Although not marked with a model number, this ratchet is substantially the same as the classic Model 350 Ratchet. One minor improvement is that the shift lever is elevated and longer, making it much easier to use.

The "APCO Mossberg" marking suggests production in 1927 or later. Since the No. 80 socket set was discontinued after 1928, the production date for the set is likely 1927-1928.

Mossberg No. 372 1/2-Drive 5 Inch Extension

Fig. 120. Mossberg No. 372 1/2-Drive 5 Inch Extension, ca. 1927-1928.

Fig. 120 shows the 1/2-drive Mossberg No. 372 5 inch extension from the No. 80 set, stamped "Frank Mossberg Corp." and "Attleboro Mass. U.S.A." with the M-Diamond logo and model number.

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

The extension is constructed from 1/2 inch square steel stock with a forged (upset) head and pinched dimples as stops.

Mossberg No. 373 1/2-Drive 10 Inch Extension

Fig. 121. Mossberg No. 373 1/2-Drive 10 Inch Extension, ca. 1927-1928.

Fig. 121 shows the 1/2-drive Mossberg No. 373 10 inch extension from the No. 80 set, stamped "Frank Mossberg Corp." and "Attleboro Mass. U.S.A." with the M-Diamond logo and model number.

The overall length is 10.1 inches, and the finish is nickel plating.

The extension is constructed from 1/2 inch square steel stock with a forged (upset) head and pinched dimples as stops.

Mossberg No. 370 1/2-Drive Sliding Tee Handle

Fig. 122. Mossberg No. 370 1/2-Drive Sliding Tee Handle, with Inset for Marking Detail, ca. 1927-1928.

Fig. 122 shows a 1/2-drive Mossberg No. 370 sliding Tee Handle, acquired with the No. 80 set but not one of the standard parts.

The top of the sliding head is stamped "Frank Mossberg Corp." and "Attleboro Mass. U.S.A." with the model number and M-Diamond logo.

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

The 1/2 inch bar has pinched tabs as stops on each end, permanently locking the sliding head on the bar.

Mossberg 1/2-Drive Chrome-Molybdenum Sockets

The Mossberg chrome-molybdenum sockets could be purchased individually, in case replacements or additional sizes were needed.

Fig. 123A. 1928 Catalog Listing for Mossberg Chrome-Molybdenum Sockets.

The scan in Fig. 123A shows the listing on page 564 of the 1928 McMaster-Carr catalog for Mossberg chrome molybdenum sockets, as it appeared just below the listing for the No. 80 socket set.

Fig. 123B. Mossberg 1/2-Drive Chrome-Molybdenum Sockets, with Inset for Top View, ca. 1927-1928.

Fig. 123B shows the three largest 1/2-drive Mossberg chrome-molybdenum sockets from the No. 80 set. Each socket is marked with the fractional size between two M-Diamond logos, but without a model number.

The socket sizes are, from the left, 3/4, 13/16, and 7/8. The finish is nickel plating.

The base of the sockets has a wide knurled band to assist with hand-turning when needed.

The top inset shows the interior of the sockets, with a recessed area just below the broaching. This was the typical construction for cold-broached sockets at that time.

Mossberg 1/2-Drive 5/8 Alloy-Steel Socket

Fig. 124. Mossberg 1/2-Drive 5/8 Socket, with Inset for Broaching, ca. 1925+.

Fig. 124 shows another example of the chrome-molybdenum series, a 1/2-drive Mossberg 5/8 hex socket, marked with the fractional size between two M-Diamond logos.

The wide knurled band at the base was a common feature for sockets at this time, meant to assist with gripping the socket when hand-turning was needed.

Mossberg 371 11/16-Drive To 1/2-Drive Adapter

Fig. 125. Mossberg 371 11/16-Drive to 1/2-Drive Adapter, with Inset for Top View, ca. Mid to Late 1920s.

Fig. 125 shows a Mossberg 371 drive adapter to convert 11/16 female drive to 1/2-drive, marked on the top with the M-Diamond logo. Note that this example has a "shelf" on top, to keep it from being pushed through the ratchet.

This adapter allows the older Mossberg 11/16 female drive ratchets (e.g. the Model 350 Ratchet) to be used with industry-standard 1/2-drive sockets.

It's currently an open question as to whether the No. 371 adapter was first produced during the years 1919-1922, when it could have been used with the "Indestructible" sockets, or not until around 1925 for use with the chrome-molybdenum sockets. An earlier production date would show that Mossberg was at least trying to broaden the appeal of the "Indestructible" sockets.

Mossberg No. 83 "Han-D-Set" 1/2-Drive Socket Set

The Mossberg No. 83 "Han-D-Set" was an inexpensive 1/2-drive socket set in a compact tool holder.

Fig. 126A. 1928 Catalog Listing for Mossberg No. 83 "Han-D-Set".

The scan in Fig. 126A shows a catalog listing for the No. 83 set from page 139 of the 1928 White Tool and Supply catalog. The listing describes the sockets as made of "Special Analysis Steel", rather than the chrome-molybdenum steel mentioned for other sets. The more economical steel kept the price low at just $1.10.

By the late 1920s 1/2-drive socket sets were being offered at remarkably inexpensive prices by retailers such as Sears Roebuck. For example, in 1929 Sears offered a "Merit Tool Ratchet Wrench Set" for just $1.98, an example of which can be seen as the Duro "Double Guarantee" Socket Set. It's likely that Mossberg's "Han-D-Set" was made with these new retail markets in mind.

Fig. 126B. Mossberg No. 83 "Han-D-Set" 1/2-Drive Socket Set, with Inset for Open View, ca. Mid to Late 1920s.

Fig. 126B shows a Mossberg No. 83 "Han-D-Set" 1/2-drive socket set, consisting of an Ell-handle and six hex sockets in a metal holder. The Ell-handle is stamped "Frank Mossberg Co." and "Attleboro, Mass. U.S.A." with the M-Diamond logo.

The socket sizes are, from the right, 7/16, 1/2, 9/16, 5/8, 11/16, and 3/4. The sockets are unmarked and are finished in nickel plating.

The sockets in the set were made of less expensive "special analysis" steel rather than chrome molybdenum, but have the same design and construction as the high-end alloy steel sockets.

Mossberg [No. 909] 1/2-Drive Ratchet Adapter

Fig. 127. Mossberg [No. 909] 1/2-Drive Ratchet Adapter, with Inset for End View, ca. Early 1930s.

Fig. 127 shows a 1/2-drive Mossberg ratchet adapter, used to provide a clutch-style release action with any drive tool. The tool is marked "Mossberg" and "Attleboro, Mass. U.S.A." on the barrel.

The overall length is 2.8 inches, and the finish is cadmium plating.

Although this tool wasn't marked with a model number, the 1929 catalog listed this as a No. 909 "Frictionless Reversible Ratchet Unit".

Based on the cadmium finish, rather than the buffed nickel specified in 1929, this example is probably from the early 1930s.

Similar examples of spring-loaded ratchet adapters were produced by several other companies, including Snap-On Wrench, Blackhawk, Walden, and Indestro. (The Snap-On tool is believed to have been the first available.) Examples can be seen as the Snap-On No. 6 Ratchet Adapter, Blackhawk T-3 Ratchet Adapter, Walden No. 1113 Ratchet Adapter, and Indestro Chromium-Vanadium Ratchet Adapter.

Mossberg No. 76 7/8-Drive Socket Set

Although we don't have any complete examples of a Mossberg's 7/8-drive socket sets, the following catalog listing shows what the tools were like.

Fig. 128A. 1928 Catalog Listing for Mossberg No. 76 7/8-Drive Socket Set.

The scan in Fig. 128A shows a catalog listing for the Mossberg No. 76 7/8-drive socket set, found on page 139 of the 1928 White Tool and Supply catalog.

The set consisted of a No. 757 18 inch ratchet, a No. 771 sliding Tee handle, Nos. 748 and 749 extensions, and eight sockets ranging from 1-1/16 to 1-13/16. Although not visible in the illustration, the extensions would have been double-male in order to work with the female-drive ratchet and sliding Tee handle.

The 7/8 square drive size was somewhat unusual, but tools in this size were also offered by Blackhawk and Snap-on from the mid 1920s to early 1930s. Examples can be seen as the Blackhawk 7/8-Drive Tools and Snap-on 7/8-Drive Tools.

Mossberg No. 771 7/8-Drive Sliding Tee Handle

This next figure shows a rare example of the Mossberg No. 771 sliding Tee handle.

Fig. 128B. Mossberg No. 771 7/8 Female Drive Sliding Tee Handle, with Insets for Top View and Marking Detail, ca. Late 1920s.

Fig. 128B shows a Mossberg No. 771 7/8 female drive sliding Tee handle, stamped "Frank Mossberg Corp." and "Attleboro Mass. U.S.A." with the model number and M-Diamond logo on the sliding head.

The overall length is 19.4 inches, and the diameter of the bar is 7/8 inch. The finish is plain steel.

The top view inset shows the 7/8 square opening in the sliding head. This tool was designed to be used with the No. 749 short double-male extension as a drive plug, or with the No. 748 14 inch extension.

The APCO Merger and Later Tools

In 1927 the Frank Mossberg Company merged with the Auto Parts Company (APCO) to become the APCO-Mossberg Company. APCO was based in Providence, Rhode Island and specialized in automotive parts and service tools for the Model T Ford.

APCO tools are mentioned in some early automotive specialty catalogs. One notable product was an offset box wrench for Model T connecting-rod bolts, offered as early as 1922 and currently the earliest known box wrench made with a double-hex (12-point) broaching.

129A. 1922 Notice for APCO Offset Box-End Wrench. [External Link]

Fig. 129A shows a notice in describing the new APCO offset box-end wrench, as published on page 28 of the February 1, 1922 issue of The Commercial Vehicle.

It mentions the intended use for the fourth connecting rod of the (Model T) Ford and notes the double-hex broaching of the opening, although the tool is incorrectly called a ratchet wrench. The price is listed as 75 cents.

An example of the APCO wrench is shown in the next figure.

APCO Early 5/8 Double-Hex Offset Box Wrench

This next tool is significant as the earliest known offset box-end wrench with a double-hex (12-point) opening.

Fig. 129B. 1922 Catalog Listing for APCO 5/8 Offset Box Wrench.

The scan in Fig. 129B shows an APCO Model T connecting rod wrench, as published on page 122 of the 1922 Western Auto "Ford Owners' Supply Book" (Eastern edition) catalog.

Fig. 129C. APCO Early 5/8 Offset Box-End Wrench, with Inset for Side View, ca. 1922.

Fig. 129C shows an early APCO 5/8 double-hex (12-point) offset box wrench, marked with "APCO" and "Pat. Applied For" forged into the handle.

The overall length is 6.7 inches, and the finish is plain steel.

The patent pending notice is believed to refer to patent #1,424,069, issued to F.W. Blackmar in 1922.

The patent describes the construction of deep offset wrenches with 12-point openings and has a rather interesting history, as it was later acquired by Snap-on around 1930.

APCO-Mossberg No. 206 5/8x11/16 Tappet Wrench

Fig. 130. APCO-Mossberg No. 206 5/8x11/16 Tappet Wrench.

Fig. 130 shows an APCO-Mossberg No. 206 5/8x11/16 tappet wrench, stamped with "APCO Mossberg Tappet Set" with the M-Diamond logo.

The overall length is 7.5 inches, and the finish is plain steel.

APCO-Mossberg 3011 13/16x7/8 Offset Box Wrench for Chevrolet Main Bearings

In the late 1920s Mossberg began offering specialty box wrenches with Bonney acting as the contract manufacturer. The next two figures show examples of these less commonly found wrenches.

Fig. 131. APCO-Mossberg 3011 13/16x7/8 Offset Box Wrench, with Insets for Side View and Marking Detail, ca. 1928.

Fig. 131 shows a Mossberg 3011 13/16x7/8 offset box wrench designed for Chevrolet main bearing service. The back side of the shank is stamped "APCO-Mossberg" and "Attleboro, Mass. U.S.A." with the M-Diamond logo at the left, shown as a close-up in the lower inset.

The overall length is 14.2 inches, and the finish is nickel plating.

This wrench is basically identical to the early production of the Bonney 2540 Main Bearing Wrench, and in fact some of Bonney's forged-in markings are still faintly visible on this example. (The top shank has a faint "CHR" of "CHROME" visible between the 5.0 and 5.5 inch marks, and the "3011" model number is stamped over the "BON" of Bonney.) Unfortunately the Bonney date code has been ground off, but the round shank style places it close to 1928 in Bonney's production.

APCO-Mossberg 3014 9/16x13/16 Specialty Box Wrench

Fig. 132. APCO-Mossberg 3014 9/16x13/16 Specialty Box Wrench, with Insets for Side View and Marking Detail, 1928.

Fig. 132 shows a Mossberg 3014 9/16x13/16 specialty box wrench, intended for Chevrolet connecting-rod and main bearing service.

The shank is marked with the M-Diamond logo plus "APCO-Mossberg Corp." and "Attleboro, Mass. U.S.A." in forged raised letters.

The shank also has a forged-in code "IT" near the small box end, as shown in the lower right inset.

The overall length is 14.0 inches, and the finish is plain steel.

This wrench was recently identified as contract production by Bonney Forge & Tool, based on the similarity of features with early Bonney specialty box wrenches, such as the Bonney 2540 Main Bearing Wrench. The identification was confirmed by the presence of a forged-in code "IT", a mark representing Bonney's date code system. (Similar marks can be found on most of Bonney's forged tools.)

The year code "T" in the Bonney Date Code System indicates production in 1928, somewhat earlier than had been first estimated.

APCO-Mossberg 971 7/16 Single-Offset Box Wrench

The next several figures show examples of Mossberg single-offset box wrenches, a style popular in the late 1920s and 1930s.

Fig. 133. APCO-Mossberg 9711 7/16 Single-Offset Box-End Wrench, with Insets for Side View and Back Side Detail.

Fig. 133 shows a Mossberg 971 7/16 single-offset box wrench, stamped "Chrome Molybdenum" and "Patent No. 1424069" on the top, with "APCO-Mossberg" and "Attleboro, Mass. Made in U.S.A." on the reverse.

The overall length is 8.4 inches, and the finish is nickel plating.

The patent notice refers to patent #1,424,069, issued to F. Blackmar in 1922 and later acquired by Snap-On. The patent describes the construction of deep offset wrenches with 12-point openings, and has been noted on 12-point wrenches made by Blue Point, Bonney, and Williams, in addition to the present example.

The single-offset wrench style was popular in the late 1920s and 1930s and appears to have originated with Blue Point. Examples of single-offset wrenches from other makers include the Blackhawk 2924, Blue Point X-20, Bonney 2818, Walden-Worcester 2114, and Williams 8128.

APCO-Mossberg 974 5/8 Single-Offset Box Wrench

Fig. 134. APCO-Mossberg 974 5/8 Single-Offset Box-End Wrench, with Insets for Side View and Back Side Detail.

Fig. 134 shows a Mossberg 974 5/8 single-offset box wrench, stamped "Chrome Molybdenum" and "Patent No. 1424069" on the top, with "APCO-Mossberg" and "Attleboro, Mass. Made in U.S.A." on the reverse.

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

The patent notice refers to patent #1,424,069, issued to F. Blackmar in 1922 and later acquired by Snap-on. The patent describes the construction of deep offset wrenches with 12-point openings.

APCO-Mossberg 975 11/16 Single-Offset Box Wrench

Fig. 135. APCO-Mossberg 975 11/16 Single-Offset Box-End Wrench, with Insets for Side View and Back Side Detail.

Fig. 135 shows a Mossberg 975 11/16 single-offset box wrench, stamped "Chrome Molybdenum" and "Patent No. 1424069" on the top, with "APCO Mossberg" plus "Attleboro, Mass." and "Made in U.S.A." on the reverse.

The overall length is 11.1 inches, and the finish is nickel plating.

The patent notice refers to patent #1,424,069, issued to F. Blackmar in 1922 and later acquired by Snap-on.

APCO-Mossberg 976 3/4 Single-Offset Box Wrench

Fig. 136. APCO-Mossberg 976 3/4 Single-Offset Box-End Wrench, with Insets for Side View and Back Side Detail.

Fig. 136 shows a Mossberg 976 3/4 single-offset box wrench, stamped "Chrome Molybdenum" and "Patent No. 1424069" on the shank, with "APCO Mossberg" and "Attleboro, Mass. Made in U.S.A." on the reverse.

The overall length is 11.7 inches, and the finish is plain steel.

The patent notice refers to patent #1,424,069, issued to F. Blackmar in 1922 and later acquired by Snap-on.

APCO-Mossberg 977 13/16 Single-Offset Box Wrench

Fig. 137. APCO-Mossberg 977 13/16 Single-Offset Box-End Wrench, with Insets for Side View and Back Side Detail.

Fig. 137 shows a Mossberg 977 13/16 single-offset box wrench, stamped "Chrome Molybdenum" and "Patent No. 1424069" on the shank, with "APCO Mossberg" and "Attleboro, Mass. Made in U.S.A." on the reverse.

The overall length is 12.3 inches, and the finish is plain steel.

The patent notice refers to patent #1,424,069, issued to F. Blackmar in 1922 and later acquired by Snap-on.

APCO-Mossberg 979 15/16 Single-Offset Box Wrench

Fig. 138. APCO-Mossberg 979 15/16 Single-Offset Box-End Wrench, with Insets for Side View and Back Side Detail.

Fig. 138 shows a Mossberg 979 15/16 single-offset box wrench, stamped "Chrome Molybdenum" and "Patent No. 1424069" on the top, with "APCO-Mossberg" and "Attleboro, Mass. Made in U.S.A." on the reverse.

The overall length is 13.8 inches, and the finish is nickel plating.

The patent notice refers to patent #1,424,069, issued to F. Blackmar in 1922 and later acquired by Snap-On.

APCO-Mossberg 1/2-Drive Extension

Fig. 139. APCO-Mossberg 1/2-Drive 10 Inch Extension.

Fig. 139 shows a 1/2-drive Mossberg extension, marked "APCO-Mossberg" and "Attleboro, Mass. Made in U.S.A." on the shank.

The overall length is 10.0 inches, and the finish is plain steel.

APCO-Mossberg 3013 Valve Adjuster

Fig. 140. APCO-Mossberg 3013 Valve Adjuster, with Insets for Construction and Marking Detail, ca. Late 1920s to Early 1930s.

Fig. 140 shows an APCO-Mossberg 3013 valve adjusting tool, stamped "APCO Mossberg" and "Attleboro, Mass. U.S.A." on the handle, along with the model number and a "Pat. 6-30-25" patent date.

The overall length is 6.8 inches, and the finish is nickel plating.

The patent date refers to patent #1,544,520, filed by E.P. Putrow in 1924 and issued in 1925.

The lower inset shows the construction of the tool, consisting of a 1/2 inch square drive tang with a rotating screwdriver bit passing through the center. The spring clips at the side secure the socket to the drive stud.

The socket is unmarked, but was acquired with the tool and is probably the original socket.

Other companies are known to have used this patent for similar tools, and an example can be seen as the Snap-on V-21 Valve Adjuster.