Kyoto Tool Company (KTC) [Page 2]

Production for Nissan

KTC began producing adjustable wrenches for Nissan OEM tool kits in the mid 1950s. These early adjustable wrenches were quite unusual (as OEM tools) both for having JIS certification and for their dual branding for KTC and Nissan.

The 1966 KTC catalog mentioned Nissan as one of their best customers, and KTC probably continued as a supplier at least into the 1970s.

Nissan adjustable wrenches were also produced by Sanjō Kikai, and examples can be seen in the section on Sanjō Kikai Production for Nissan.

Early Dual-Branded KTC-Nissan Wrenches

KTC supplied JIS-certified adjustable wrenches to Nissan beginning around 1953, with initial production outsourced to Yamaco.

Early production for Nissan was unusual not only for the JIS certification, but also for being dual-branded for KTC, even down to the "Nijūmarukyo" logo. As would be expected of tools bearing KTC's name, the wrenches were finely finished with polished faces and nickel plating. We will refer to these as KTC-Nissan wrenches, to emphasize the unusual dual branding.

The KTC-Nissan wrenches were produced in 200mm and 250mm sizes, and although the 250mm size is quite rare, the 200mm size was apparently produced in huge quantities and is very common. We are fortunate to have several examples available for display.

KTC-Nissan 200mm Adjustable Wrenches

The next three figures show examples of KTC-Nissan adjustable wrenches, with some differences in construction and markings.

Fig. 39. KTC-Nissan "51 N" 200mm Adjustable Wrench, with Insets for Back Side, Side View, and Construction Detail, ca. Late 1954 to 1959.

Fig. 39 shows a KTC-Nissan 200mm adjustable wrench, marked with the Nissan logo and "Boron Steel" forged into the front, with "KYOTO" and "K.T.C." plus the Nijūmarukyo logo and JIS-Circle logo forged into the back.

The wrench is also marked with a "51 N" code forged into the front near the hanging hole.

The lower inset shows a close-up of the open jaws, illustrating the rounded transition at the corner of the fixed jaw and the inset convex cutaway of the movable jaw. Note also the full width of the tailpiece of the movable jaw.

Note the relatively thick head, as illustrated in the top inset.

The overall length is 8.2 inches and the maximum opening is 0.9 inches. The head thickness was measured at 0.59 inches.

The finish is nickel plating with polished faces.

This wrench is also displayed in an earlier section as the KTC "Nissan" Adjustable Wrench, as an example of KTC's first-generation adjustable wrenches.

Fig. 40. KTC-Nissan "6 N" 200mm Adjustable Wrench, with Insets for Back Side, Side View, and Construction Detail, ca. Late 1954 to 1959.

Fig. 40 shows a KTC-Nissan 200mm adjustable wrench, marked with the Nissan logo and "Boron Steel" forged into the front, with "KYOTO" and "K.T.C." plus the Nijūmarukyo logo and JIS-Circle logo forged into the back.

The wrench is also marked with a "6 N" code forged into the front near the hanging hole.

The overall length is 8.1 inches and the maximum opening is 1.0 inches. The head thickness was measured at 0.54 inches.

The finish is nickel plating with polished faces, with minor losses due to wear and rust

Fig. 41. KTC-Nissan "61 N" 200mm Adjustable Wrench, with Insets for Back Side, Side View, and Construction Detail, ca. Late 1954 to 1959.

Fig. 41 shows a third KTC-Nissan 200mm adjustable wrench, marked with the Nissan logo and "Boron Steel" forged into the front, with "KYOTO" and "K.T.C." plus the Nijūmarukyo logo and JIS-Circle logo forged into the back.

The wrench is also marked with a "61 N" code forged into the front near the hanging hole.

The overall length is 8.2 inches and the maximum opening is 1.0 inches. The head thickness was measured at 0.51 inches.

The finish is nickel plating with polished faces, with minor losses due to wear and rust

The measured head thickness of the first wrench ("51 N") at 0.59 inches is substantially greater than the second ("6 N") at 0.54 inches and the third ("61 N") at 0.51 inches. We have two more examples of KTC-Nissan wrenches, one with lot number "33 N" and "61 N", and the head thicknesses were measured at 0.54 and 0.51 inches respectively.

The differences in head thickness suggest that KTC may have been experimenting with different grades of steel and adjusting its engineering accordingly, and the thinner heads probably correspond with later production.

A comparison of the back side markings of the three wrenches shows that the layout in each is slightly different from the others. For example, in the first wrench the "KYOTO ... K.T.C." marking is more spread out, leading to a smaller gap between the markings and JIS symbol. We plan to make a composite photo of the back sides to simplify the comparison.

Later Nissan Wrenches

Later Nissan 200mm adjustable wrenches were marked only for Nissan, with no obvious marks to indicate KTC (or any other company) as the maker. In addition, the wrenches were no longer JIS certified and were somewhat roughly finished, with faces ground flat but not polished, and with a zinc (or possibly cadmium) plated finish.

Interestingly though, the 250mm size continued to be JIS certified, and while the branding was only for Nissan, the known examples were marked with the JIS ID for Sanjō Kikai ("Sanki"). An example can be seen as the [Sanki] Nissan 250mm Adjustable Wrench.

Our hypothesis is that at some point Nissan had to reduce the costs for its OEM tool kits, and since the 200mm size was made in much higher volume than the 250mm size, these would have been the obvious targets for cost reduction. The dual-branded KTC-Nissan wrenches probably came at a premium price, both for the JIS certification and for the prestige branding by KTC, so there could have been substantial savings in dropping JIS certification and going with Nissan-only branding and a lesser finish.

At the same time, the company maintained JIS certification for the lower-volume 250mm size, but with Nissan-only branding and a less expensive manufacturer.

The timing for these changes is still uncertain, but we think that sometime around 1960 is a good estimate.

The construction features of later Nissan 200mm adjustable wrenches closely resemble the earlier wrenches, with a rounded transition at the fixed jaw, a full-width tailpiece, and a maru style jaw outline. With KTC known to be a supplier to Nissan, it's highly likely that the adjustable wrenches were made by KTC.

[KTC] Nissan 200mm Adjustable Wrench

Fig. 42. Nissan 200mm Adjustable Wrench, with Insets for Back Side, Side View, and Construction Detail, ca. 1960s to Early 1970s.

Fig. 42 shows a later Nissan 200mm adjustable wrench, marked with "Nissan Motor" and the Nissan logo forged into the front. The back side is unmarked.

The lower inset shows a close-up of the open jaws, illustrating the rounded transition at the corner of the fixed jaw and the inset convex cutaway of the movable jaw.

Note also the full width of the tailpiece of the movable jaw.

The overall length is 8.0 inches and the maximum opening is 0.9 inches. The head thickness was measured at 0.51 inches.

The finish is zinc plating, with extensive losses due to rust.

This wrench was very rusty when we acquired it, but after an overnight soak in the electrolytic derusting bath, we were able to take the rusty areas down to bare metal in most places.

The plain hanging hole suggests production during the 1960s to early 1970s.

[KTC] Later Nissan 200mm Adjustable Wrench

Fig. 42B. Later Nissan 200mm Adjustable Wrench, with Insets for Back Side, Side View, and Construction Detail, ca. Early 1970s.

Fig. 42B shows a later Nissan 200mm adjustable wrench with a ridge around the hanging hole, marked with "Nissan Motor" and the Nissan logo forged into the front. The back side is unmarked.

The lower inset shows a close-up of the open jaws, illustrating the rounded transition at the corner of the fixed jaw and the inset convex cutaway of the movable jaw.

Note also the full width of the tailpiece of the movable jaw.

The overall length is 8.1 inches and the maximum opening is 1.0 inches. The head thickness was measured at 0.59 inches.

The finish is zinc (or possibly cadmium) plating.

We disassembled the wrench for cleaning and noted that the pin securing the worm gear is threaded on the inside end.

In estimating the production date for this wrench we noted that KTC changed to using a ridge around the hanging hole sometime in the early to mid 1970s, and in the same timeframe also changed to a movable jaw with a tapered tailpiece. We have observed photographs wrenches very similar to the present example but with a tapered tailpiece, suggesting that the present example is in the earlier range of changes. These considerations lead to an early 1970s estimate.

The head of this wrench is substantially thicker than the previous example (0.59 vs. 0.51 inches), suggesting that the steel used for the wrench has reverted to a less expensive carbon steel formulation.

Production for Fuller and Award Brands

The figures in this section show examples of tools produced by KTC for the Fuller Tool Company and its Award subsidiary. Award Tool was founded in 1963 as a reseller of hand tools, and from 1965 onward operated as a subsidiary of Fuller. (It's possible that KTC might have provided production for Award while it was still independent, but we do not have any specific evidence.)

Wrenches

Wrenches made for Fuller and Award have been observed in three styles as noted in the list below. The sections will offer production date estimates based on catalog references when available, but with a large degree of uncertainty for one style.

More discussion on these wrenches can be found in the section on Fuller Wrenches.

Recessed Oval Panels
Wrenches with recessed oval panels are believed to represent the earliest production period and were likely made beginning in the early 1960s. Wrenches in this style were made with forged-in markings, and the known examples were marked for chrome vanadium steel.

The open-end wrenches of this generation closely resemble KTC's own production, as illustrated on page 8 [External Link] of the 1966 KTC catalog.
Raised Oval Panels
The second style was characterized by raised oval panels and stamped markings. The wrenches were marked either as "Drop Forged" or "Forged Alloy", but no specific alloy references are known.

Another characteristic of this style is a forged-in "Fx" manufacturing code, with the "F" prefix believed to indicate a Fuller-specific forging die.

Currently we do not have a clear catalog reference for this style, but the wrenches are believed to have been sold as wrench sets in plastic pouches.
Raised Parallelogram Panels
The third style is characterized by raised paralleogram panels and stamped markings, with production commencing in the late 1970s. The earliest published reference is in a 1979 catalog, which can be seen as the Catalog Listing of Fuller Parallelogram Wrenches.

Wrenches in this style were usually marked with a specific alloy as either "Chrome Vanadium" or "Chrome Molybdenum".

This style has a forged-in manufacturing code of the form "Ux".

The figures below will show examples of the different styles.

[KTC] Fuller 11/16x3/4 Open-End Wrench

Fig. 43. Fuller 11/16x3/4 Open-End Wrench, with Inset for Back Side, ca. 1980s.

Fig. 43 shows a Fuller 11/16x3/4 open-end wrench with raised oval panels, stamped with "Fuller" and the fractional sizes on the front panel, with "Drop Forged" and "Japan" plus the KTC-Oval logo on the back panel.

The back side of the shank also has a forged-in "F24" code visible at the right.

The overall length is 7.3 inches, and the finish is chrome plating with polished faces.

[KTC] Fuller 3/4x7/8 Open-End Wrench

Fig. 44. Fuller 3/4x7/8 Open-End Wrench, with Inset for Back Side, ca. 1960s to Mid 1970s.

Fig. 44 shows an early Fuller 3/4x7/8 open-end wrench with recessed oval panels, marked with "*Fuller*" and "Chrome Vanadium" plus the fractional sizes forged into the front, with "Drop Forged" and "Japan" plus the KTC-Oval logo forged into the back.

The overall length is 8.6 inches, and the finish is chrome plating, with extensive losses due to wear and rust.

This wrench closely resembles the illustration on page 8 [External Link] of the 1966 KTC catalog, which is consistent with our estimate of production in the 1960s.

[KTC] Fuller/Award 15/16x1 Open-End Wrenches

The next figures show two generations of Fuller/Award 15/16x1 inch wrenches.

Fig. 45. [KTC] Award 15/16x1 Open-End Wrench, with Insets for Back Side and Marking Detail, ca. Mid 1960s to Mid 1970s.

Fig. 45 shows an Award 15/16x1 open-end wrench with recessed oval panels, marked with "Chrome Vanadium" and the fractional sizes forged into the shank, with "Drop Forged" and "Japan" plus the KTC-Oval logo forged into the back side.

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

The KTC-Oval logo indicates that the wrench was produced by the Kyoto Tool Company.

Fig. 46. Fuller 15/16x1 Inch Open-End Wrench, with Inset for Back Side, ca. Late 1970s to 1980s.

Fig. 46 shows a Fuller 15/16x1 inch open-end wrench with parallelogram panels, stamped with "Fuller" and the fractional sizes on the front panel, with "Chrome Molybdenum" and "Japan" plus the KTC-Oval logo on the back panel.

The back side of the shank also has a forged-in code "U02" visible at the right.

The overall length is 11.9 inches, and the finish is chrome plating with polished faces.

[KTC] Fuller 13x15mm Open-End Wrench

Fig. 47. Fuller 13x15mm Open-End Wrench, with Inset for Back Side, ca. 1980s.

Fig. 47 shows a Fuller 13x15mm open-end wrench with raised oval panels, stamped with "Fuller" and the metric sizes on the front panel, with "Drop Forged" and "Japan" plus the KTC-Oval logo on the back panel.

The back side of the shank also has a forged-in "F35" code visible at the right.

The overall length is 5.9 inches, and the finish is chrome plating with polished faces.

[KTC] Fuller 17x19mm Open-End Wrench

Fig. 48. Fuller 17x19mm Open-End Wrench, with Inset for Back Side, ca. 1980s.

Fig. 48 shows a Fuller 17x19mm open-end wrench with raised oval panels, stamped with "Fuller" and the metric sizes on the front panel, with "Drop Forged" and "Japan" plus the KTC-Oval logo on the back panel.

The back side of the shank also has a forged-in "F79" code visible at the right.

The overall length is 7.1 inches, and the finish is chrome plating with polished faces.

[KTC] Award 3/8 Combination Wrench

Fig. 49. [KTC] Award 3/8 Combination Wrench, with Insets for Back Side and Edge View, ca. Mid 1960s to Mid 1970s.

Fig. 49 shows an Award 3/8 combination wrench with recessed oval panels, marked with "Award" and "Chrome Vanadium" plus the fractional size forged into the shank, with "Drop Forged" and "Japan" plus the KTC-Oval logo forged into the back side.

The overall length is 4.6 inches, and the finish is chrome plating with polished faces.

[KTC] Fuller/Award 7/16 Combination Wrenches

The next figures show two generations of the Fuller/Award 7/16 combination wrenches.

Fig. 50. Award "KTC" 7/16 Combination Wrench, with Insets for Back Side and Side View, ca. Mid 1960s to Mid 1970s.

Fig. 50 shows an Award 7/16 combination wrench with recessed oval panels, marked with "Award" and "Chrome Vanadium" plus the fractional size forged into the front panel, with "Drop Forged" and "Japan" plus the KTC-Oval logo forged into the back panel.

The overall length is 5.5 inches, and the finish is chrome plating with polished faces.

Fig. 51. Fuller 7/16 Combination Wrench, with Insets for Back Side and Edge View, ca. 1980s.

Fig. 51 shows a Fuller 7/16 combination wrench with raised oval panels, stamped with "Fuller" and the fractional size on the front panel, with "Forged Alloy" and "Japan" plus the KTC-Oval logo on the back panel.

The back side of the shank also has a forged-in code "F4" visible at the left.

The overall length is 5.0 inches, and the finish is chrome plating with polished faces and ends.

[KTC] Fuller 1/2 Combination Wrench

Fig. 52. Fuller 1/2 Combination Wrench, with Insets for Back Side and Edge View, ca. 1980s.

Fig. 52 shows a Fuller 1/2 combination wrench with raised oval panels, stamped with "Fuller" and the fractional size on the front panel, with "Forged Alloy" and "Japan" plus the KTC-Oval logo on the back panel.

The back side of the shank also has a forged-in code "F6" visible at the left.

The overall length is 5.5 inches, and the finish is chrome plating with polished faces and ends.

[KTC] Fuller/Award 5/8 Combination Wrenches

The next figures show three generations of the Fuller/Award 5/8 combination wrenches.

Fig. 53. Award "KTC" 5/8 Combination Wrench, with Insets for Back Side and Side View, ca. Mid 1960s to Mid 1970s.

Fig. 53 shows an Award 5/8 combination wrench with recessed oval panels, marked with "Award" and "Chrome Vanadium" plus the fractional size forged into the shank, with "Drop Forged" and "Japan" plus the KTC-Oval logo forged into the back side.

The overall length is 7.8 inches, and the finish is chrome plating, with losses due to wear.

Fig. 54. Fuller 5/8 Combination Wrench, with Insets for Edge View and Back Side Detail, ca. 1980s.

Fig. 54 shows a Fuller 5/8 combination wrench with raised oval panels, stamped with "Fuller" and the fractional size on the front panel, with "Forged Alloy" and "Japan" plus the KTC-Oval logo on the back panel.

The back side of the shank also has a forged-in "F6" code visible at the left.

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

Fig. 55. Fuller 5/8 Combination Wrench, with Insets for Back Side and Edge View, ca. late 1970s to 1980s.

Fig. 55 shows a Fuller 5/8 combination wrench with raised parallelogram panels, stamped with "Fuller" and the fractional size on the front panel, with "Chrome Molybdenum" and "Japan" plus the KTC-Oval logo on the back panel.

The back side of the shank also has a forged-in "U0" code visible at the left.

The overall length is 7.8 inches, and the finish is chrome plating with polished faces and ends.

[KTC] Fuller 11/16 Combination Wrench

Fig. 56. Fuller 11/16 Combination Wrench, with Insets for Back Side and Edge View, ca. Late 1970s to 1980s.

Fig. 56 shows a Fuller 11/16 combination wrench with raised parallelogram panels, stamped with "Fuller" and the fractional size on the front panel, with "Chrome Vanadium" and "Japan" plus the KTC-Oval logo on the back panel.

The back side of the shank also has a forged-in "U1" code visible (upside-down) at the left.

The overall length is 8.6 inches, and the finish is chrome plating with polished faces and ends.

[KTC] Fuller 3/4 Combination Wrench

Fig. 57. Fuller 3/4 Combination Wrench, with Insets for Edge View and Back Side Detail, ca. Late 1970s to 1980s.

Fig. 57 shows a Fuller 3/4 combination wrench with raised parallelogram panels, stamped with "Fuller" and the fractional size on the front panel, with "Chrome Molybdenum" and "Japan" plus the KTC-Oval logo on the back panel.

The back side of the shank also has a forged-in "U4" code visible at the left.

The overall length is 9.5 inches, and the finish is chrome plating with polished faces and ends.

[KTC] Fuller No. 12 12 Inch Adjustable Wrench

Fig. 58. [KTC] Fuller No. 12 12 Inch Adjustable Wrench, with Insets for Back Side, Side View, Construction Detail, and Marking Detail, ca. Mid 1960s to Early 1970s.

Fig. 58 shows a Fuller No. 12 12 inch adjustable wrench, marked with "Fuller No. 12" and "Chrome Alloy" forged into the front, with "Full Drop Forged" forged into the back side.

The back side is also marked with the KTC-Oval logo and "JAPAN" forged along a curved arc near the hanging hole.

The lower inset shows a close-up of the open jaws, illustrating the rounded corner of the fixed jaw and the inset convex cutaway of the movable jaw.

The overall length is 12.0 inches, and the maximum opening is 1.4 inches. The finish is chrome plating with polished faces.

We were able to remove the pin securing the worm gear on this wrench and noted that it is threaded on the inside end.

This wrench is a nearly perfect embodiment of the "KTC Style" of adjustable wrenches as expressed on page 11 [External Link] of the 1966 KTC catalog. Note in particular the details of the jaw construction, the full width of the tailpiece of the movable jaw, and the absence of a ridge around the hanging hole.

KTC is known to have relied heavily on Hokuyo Sangyō ("Sanki") for production of adjustable wrenches, but we believe that this wrench is an example of KTC's own production. This conclusion is based on the close match of all features with the 1966 catalog illustration and the relatively large hanging hole compared to Sanki.

In addition, the presence of the KTC-Oval logo on a Fuller wrench strongly suggests KTC production, though of course the company's production partners were authorized to replicate the logo. There are numerous examples of Fuller wrenches made by and marked with "Sanki", and if this wrench had been made by Sanki, it probably would have been marked that way.

[KTC] Later Fuller No. 10 "KTC" 10 Inch Adjustable Wrench

Fig. 59. Later Fuller No. 10 "KTC" 10 Inch Adjustable Wrench, with Insets for Back Side, Side View, Construction Detail, and Marking Detail, ca. Mid 1970s.

Fig. 59 shows a later Fuller No. 10 10 inch adjustable wrench, marked with "Fuller No. 10" and "Chrome Alloy" forged into the front, with "Full Drop Forged" forged into the back side.

The back side is also marked with the KTC-Oval logo and "JAPAN" forged along a curved arc near the hanging hole.

The lower inset shows a close-up of the open jaws, illustrating the rounded corner of the fixed jaw and the corresponding inset convex cutaway of the movable jaw.

The overall length is 10.1 inches, and the maximum opening is 1.2 inches.

The finish is chrome plating with polished faces.

We disassembled the wrench for cleaning and noted that the pin securing the worm gear is threaded on the outside end.

The construction of this wrench is very similar to the KTC 300mm Adjustable Wrench shown in an earlier figure. Note in particular the details of the jaw construction, the tapered tailpiece of the movable jaw, the "spear type" jaw outline, and the ridge surrounding the hanging hole. These details identify the wrench as representative of KTC's third-generation adjustable wrench style.

The main visible changes from KTC's second to third generation styles are the ridge around the hanging hole and the tapered tailpiece of the movable jaw. An important change in construction also occurred with the switch from inside to outside threads on the pin securing the worm gear.

Fig. 60. Close-up of Jaw Parts for Fuller "KTC" 10 Inch Adjustable Wrench.

KTC's change to use outside threads for its adjustable wrenches was completely unexpected, as we don't know of any other company that has changed this construction detail, especially after using inside threads for so many years.

Fig. 60 shows a close-up of the disassembled jaw parts for the later Fuller No. 10 "KTC" 10 inch adjustable wrench. From top to bottom, the parts are the movable jaw, the worm gear, a small spring, and the threaded pin.

Note that the pin is threaded on the outside (slotted) end.

[KTC] Fuller "Super/Quality" 14 Inch Heavy-Duty Pipe Wrench

Fig. 61. Fuller 14 Inch Heavy-Duty Pipe Wrench, with Insets for Back Side, Side View, and Marking Detail, ca. Late 1960s to 1980s.

Fig. 61 shows a Fuller 14 inch heavy-duty (Ridgid pattern) pipe wrench, marked with "Fuller" and "Super/Quality" cast into the front, and with the same markings plus "Japan" cast into the back side.

The movable jaw is marked with "Drop Forged" (partially visible) and the KTC-Oval logo forged into one side, with graduations for the opening size on the other side.

The overall length is 12.5 inches closed and approximately 15.6 inches fully extended. The finish is plain steel and red paint.

This wrench is nearly identical (except for markings) to the [KTC] Sears 30852 "BF" 14 Inch Pipe Wrench.

Other Tools

In addition to wrenches, adjustable wrenches, and pipe wrenches, KTC is known to have supplied Fuller with bolt cutters.

In addition, KTC's Kyoto Kōki subsidiary may have supplied Fuller with slip-joint pliers, but we're still gathering evidence to show a connection. In contrast to the case for wrenches, no examples of Fuller pliers have been found with a "KTC" marking.

Production for Sears Roebuck

KTC supplied tools to Sears Roebuck for several of its brands, including "Sears", "Companion", and "Craftsman". Contract production for Sears was marked with a "BF" code.

Tools in the "BF" series were introduced in 1964 and KTC was involved from the beginning with production of carbon-steel forged wrenches, which were made as copies of Dunlap wrenches from the mid to late 1950s. Early production also included adjustable wrenches.

A more extensive discussion of the development of the "BF" series can be found in our article on Distributor "BF".

We recently (2024) discovered that prior to the start of the "BF" series, KTC and Toho Kōki provided "Dunlap" brand adjustable wrenches to Sears in 1962 as part of a trial order. (Sears sometimes ran test marketing experiments before deciding on a new supplier.) The Dunlap wrenches were apparently well received by the market, and the "BF" series was launched shortly afterwards.

Carbon Steel Wrenches

Sears carbon steel wrenches were one of their most popular products and were available in open-end, combination, and box-end styles.

Additional examples can be seen in the section on Sears Carbon Steel Wrenches in our article on later Craftsman tools.

[KTC] Sears "BF" 9/16x5/8 Open-End Wrenches

The next figures show two generations of the Sears "BF" 9/16x5/8 wrench, with minor differences in the markings and length.

Fig. 62. [KTC] Sears "BF" 9/16x5/8 Open-End Wrench, with Insets for Back Side and Side View, ca. 1964 to Mid 1960s.

Fig. 62 shows an early Sears "BF" 9/16x5/8 open-end wrench with depressed panels, marked with "Sears" and the fractional sizes forged into the front panel, with "Drop Forged" between "B.F" and "Japan" forged into the back panel.

The top inset shows a side view of the wrench, with traces of the trimming operation visible on the edge.

The overall length is 6.1 inches, and the finish is chrome plating with polished faces.

This wrench is marked with the first generation variant of the KTC Standard Forged Markings, which indicates production by KTC for the Sears "BF" contract. Note that in this example the "BF" and "Japan" markings are split by "Drop Forged", and the back panel doesn't repeat the size markings.

The first generation marking suggests production from 1964 to the mid 1960s.

Fig. 63. [KTC] Later Sears "BF" 9/16x5/8 Open-End Wrench, with Insets for Back Side and Side View, ca. Mid 1970s+.

Fig. 63 shows a later Sears "BF" 9/16x5/8 open-end wrench with depressed panels, marked with "Sears" and the fractional sizes forged into the front panel, with "Drop Forged" and "BF Japan" plus the fractional sizes forged into the back panel.

The top inset shows a side view of the wrench, illustrating the smoothly finished and polished edge of the wrench.

The overall length is 6.4 inches, and the finish is chrome plating with polished faces.

This wrench is marked with the third generation variant of the KTC Standard Forged Markings. which indicates production by KTC for the Sears "BF" contract. Note that the "BF" and "Japan" markings are joined together, and the size markings are repeated on the back panel.

The third generation marking suggests production from the mid 1970s onward.

Sears "BF" 5/8 Combination Wrenches

The next figures show two generations of the Sears "BF" 5/8 combination wrench, with minor differences in the markings.

Fig. 64. Sears "BF" 5/8 Combination Wrench, with Insets for Back Side and Side View, ca. 1964 to Mid 1960s.

Fig. 64 shows an early Sears 5/8 combination wrench with depressed panels, marked with "Sears" and the fractional size forged into the front panel, with "Drop Forged" between "B.F" and Japan" forged into the back side.

The top inset shows a side view of the wrench. Note that the edge of the shank has been ground smooth, but a few traces of the trimming process still remain.

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

This wrench has an early variation of the KTC Standard Forged Markings with "B.F" and "Japan" on opposite ends of the back panel.

Fig. 65. Sears "BF" 5/8 Combination Wrench, with Insets for Back Side and Side View, ca. Mid 1960s to 1970s.

Fig. 65 shows a somewhat later Sears 5/8 combination wrench with depressed panels, marked with "Sears" and the fractional size forged into the front panel, with "Drop Forged" and "BF Japan" plus the fractional size forged into the back side.

The top inset shows a side view of the wrench. Note that the edge of the shank has been ground smooth, and the edges of the open-end are rounded and polished.

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

The KTC Standard Forged Markings identify this wrench as production by KTC for the Sears "BF" contract.

These wrenches closely resemble the Dunlap "LC" 5/8 Combination Wrench shown in another article, strongly suggesting that the Sears "BF" wrenches were made as intentional copies.

[KTC] Sears "BF" 9/16x5/8 Offset Box-End Wrench

Fig. 66. Sears "BF" 9/16x5/8 Offset Box-End Wrench, with Insets for Back Side and Side View, ca. Mid 1970s+.

Fig. 66 shows a Sears 9/16x5/8 offset box-end wrench with depressed panels, marked with "Sears" and the fractional sizes forged into the front panel, with "Forged" and "BF Japan" plus the fractional sizes forged into the back panel.

The overall length is 9.4 inches, and the finish is chrome plating, with losses due to wear and rust.

This wrench can be identified as production by KTC based on a display in KTC's tool museum, which shows a wrench closely resembling this example identified as contract ("OEM") production for Sears. The wrench in the exhibit has the same distinctive production characteristics, including the short horizontal sections joining the box ends.

This wrench was designed as an intentional copy of Dunlap offset box wrenches made by Lectrolite, an example of which can be seen as the Dunlap "LC" 3/8x7/16 Offset Box-End Wrench. Note the precisely formed depressed panels with crisp forged-in markings, a hallmark of KTC's production. The marking for "BF Japan" is made with a smaller font and placed to the right of the "Forged" marking.

We will refer to the marking style of this wrench as the KTC Standard Forged Markings and will use this to identify other examples of KTC's production.

[KTC] Dunlap "Japan" 6 Inch Adjustable Wrench

We recently (2024) discovered that in 1962 Sears placed a trial order for "Dunlap" brand adjustable wrenches from its prospective Japanese suppliers. We haven't found any mention of Japanese imports for Dunlap in the catalogs, and presumably these wrenches were sold only in stores.

Fig. 67. [KTC] Dunlap "Japan" 6 Inch Adjustable Wrench, with Insets for Back Side, Side View, and Construction Detail, ca. 1962.

Fig. 67 shows a Dunlap 6 inch adjustable wrench, marked with the Dunlap oval logo and "Chrome" over "Alloy Steel" forged into the shank, with "Full Drop Forged" and "Japan" forged into the back side.

The center inset shows the construction of the jaws. Note the rounded transition at the corner of the fixed jaw, with a corresponding inset convex cutaway on the movable jaw.

The overall length is 6.1 inches and the maximum opening is 0.8 inches. The finish is chrome plating with polished faces.

We verified that the pin securing the worm gear is threaded on the inside end. However, it wasn't easy to remove the pin — the threads push the head of the pin only slightly beyond the edge of the wrench, and we had to grasp the pin with needlenose pliers to pull it out.

This wrench has been identified as part of a trial order placed by Sears in 1962 and imported by the Fuller Orient Corporation. At that time Fuller's primary manufacturing partners were KTC and Toho Kōki, and the inside threads on the pin of this wrench identify KTC as the maker.

Note the round or "maru" outline of the jaws in the center inset. In later years KTC adopted a "spear-type" outline, and this wrench will help us narrow the date estimate for the change.

The distinctive stacked "Chrome/Alloy Steel" marking is a production characteristic believed to be unique to KTC for its 6 inch adjustable wrenches. This same marking has also been observed on Sears brand 6 inch adjustable wrenches.

[KTC] Sears [30870] "BF" 6 Inch Adjustable Wrenches

The next figures show two generations of the Sears [30870] 6 inch adjustable wrench, both identified as production from KTC but with differences in the features.

Fig. 68. Sears [30870] "BF" 6 Inch Adjustable Wrench, with Insets for Back Side, Side View, and Construction Detail, ca. 1964-1965.

Fig. 68 shows an early Sears [30870] 6 inch adjustable wrench, marked with "Sears" and "Chrome" over "Alloy Steel" forged into the front, with "Full Drop Forged" and "BF Japan" forged into the back.

The lower inset shows a close-up of the fully open jaws, illustrating the rounded corner of the fixed jaw and the corresponding inset convex cutaway of the movable jaw.

The overall length is 6.1 inches and the maximum opening is 0.8 inches. The finish is chrome plating with polished faces, with some losses due to rust.

The wrench is not marked with a model number, but the early catalogs listed the 6 inch size as model 30870.

The construction of this wrench is nearly identical to the [KTC] Dunlap "Japan" 6 Inch Adjustable Wrench, and the presence of the distinctive stacked "Chrome/Alloy Steel" marking confirms KTC as the maker.

The pin holding the worm gear of this wrench is frozen, so we were not able to confirm the use of inside threads, but based on other details we are confident that the wrench was made by KTC.

Note the round or "maru" outline of the jaws in the center inset. In later years KTC adopted a "spear-type" outline, and this wrench helps us narrow the date estimate for the change.

Continuity with the earlier Dunlap example plus the use of a "maru" outline and a ridge around the hanging hole lead to an early date estimate of 1964-1965 for this example.

Fig. 69. Sears [30870] "BF" 6 Inch Adjustable Wrench, with Insets for Back Side, Side View, and Construction Detail, ca. 1966-1969.

Fig. 69 shows a somewhat later Sears [30870] 6 inch adjustable wrench, marked with "Sears" and "Chrome" over "Alloy Steel" forged into the front, with "Full Drop Forged" and "BF Japan" forged into the back.

The lower inset shows a close-up of the fully open jaws. Note the rounded corner of the fixed jaw, the inset convex cutaway in the movable jaw, and the full width at the end of the tailpiece.

The overall length is 6.0 inches and the maximum opening is 0.8 inches. The finish is chrome plating with polished faces, with minor spots of corrosion.

The wrench is not marked with a model number, but based on the catalogs would have been model 30870.

The markings on this wrench are nearly identical to the Early Sears "BF" 6 Inch Adjustable Wrench shown above, and the presence of the distinctive stacked "Chrome/Alloy Steel" marking confirms KTC as the maker.

We were not able to remove the pin holding the worm gear, but the walls of the bore are smooth, confirming the use of inside threads as expected for KTC.

Although the markings of this wrench match the earlier Sears 6 inch wrench, the construction differs in the use of elongated "spear type" jaws and a plain hanging hole. In these aspects the wrench is nearly identical to the Sears "BF" 8 Inch Adjustable Wrench shown below, and also matches the illustration on page 11 [External Link] of the 1966 KTC catalog.

The absence of a model number suggests production before 1970, when Sears began requiring model number markings. The "spear type" jaws and plain hanging hole suggest production in 1966 or later, as earlier production by KTC for Sears had "maru" outline jaws and a ridge around the hanging hole.

The reader may wish to review the Dunlap "Japan" 6 Inch Adjustable Wrench, the Early Sears "BF" 6 Inch Adjustable Wrench, and the present example as a progression, as these represent three generations of KTC production for Sears.

[KTC] Sears [30871] "BF" 8 Inch Adjustable Wrench

Fig. 70. [KTC] Sears [30871] "BF" 8 Inch Adjustable Wrench, with Insets for Back Side, Side View, and Construction Detail, ca. 1966-1969.

Fig. 70 shows a Sears [30871] 8 inch adjustable wrench, marked with "Sears" and "Chrome Alloy Steel" forged into the shank, with "Full Drop Forge" and "BF Japan" on the back side.

The lower inset shows a close-up of the fully open jaws. Note the rounded corner of the fixed jaw, the inset convex cutaway in the movable jaw, and the full width at the end of the tailpiece.

The overall length is 7.9 inches, and the finish is chrome plating with polished faces.

The wrench is not marked with a model number, but based on the catalogs would have been model 30871.

This wrench closely resembles the illustration on page 11 [External Link] of the 1966 KTC catalog, in particular with the jaw details noted above and the absence of a ridge around the hanging hole. Note also the elongated "spear type" jaw outline.

Another construction characteristic noted for this wrench is that the pin securing the worm gear is threaded on the inside end.

In addition to closely matching the KTC catalog illustration, this wrench is nearly identical (except for markings) to the [KTC] Fuller No. 12 Adjustable Wrench displayed in an earlier figure. The additional comparison with the Fuller example provides strong evidence that this wrench was produced by KTC.

The absence of a model number suggests production from 1964-1969, after which Sears began requiring model number markings. The "spear type" outline of the jaws and plain hanging hole suggest production in 1966 or later, as earlier production by KTC for Sears had "maru" outline jaws and a ridge around the hanging hole.

Pipe Wrenches

KTC began supplying pipe wrenches for the Sears "BF" series in 1968 following an intensive development program.

[KTC] Sears 30852 "BF" 14 Inch Heavy-Duty Pipe Wrench

In 1968 Sears offered Japanese heavy-duty pipe wrenches in models 30851 and 30852, with sizes 10 and 14 inches respectively. This next figure shows an example of the larger model.

Fig. 71. Sears 30852 "BF" 14 Inch Pipe Wrench, with Insets for Back Side, Top View, and Marking Detail, ca. Late 1960s to 1970s.

Fig. 71 shows a Sears 30852 14 inch heavy-duty (Ridgid pattern) pipe wrench, marked with "Sears" and "Heavy Duty" plus the model number cast into the shank, with the same markings plus "14" and "Japan" cast into the back side.

The jaw is marked "Drop Forged" (partly obscured) with the KTC-Oval logo and "BF" forged into the recessed panel, as shown in the small inset.

The overall length is 12.8 inches closed and approximately 15.3 inches fully extended. The finish is plain steel and red paint.

For this wrench we don't have to guess the manufacturer, as KTC was thoughtful enough to place their well-known logo on the movable jaw.

By 1978 Sears was offering Japanese heavy-duty pipe wrenches under its "Craftsman" brand, and although we don't have an example available, we strongly suspect that KTC was the maker of the Craftsman pipe wrenches as well.

[KTC] Sears [30884] "BF" 18 Inch Stillson-Pattern Pipe Wrench

By 1969 KTC was supplying Stillson-pattern pipe wrenches to Sears in a distinctive design with a paneled jaw carrier and a hidden spring.

Fig. 72. [KTC] Sears [30884] "BF" 18 Inch Stillson-Pattern Pipe Wrench, with Insets for Back Side, Top View, and Marking Detail, ca. 1969.

Fig. 72 shows a Sears [30884] 18 inch Stillson-pattern pipe wrench, marked with "Sears" forged into the handle, with "Japan BF" forged into the back side.

The overall length is 15.9 inches closed and approximately 18.5 inches fully extended. The finish is plain steel and red paint.

The wrench is not marked with a model number, but based on the catalogs would have been model 30884.

The absence of a model number suggests production before 1970, and the first catalog listing in 1969 leads to a 1969 production date estimate for this wrench.

This wrench can be recognized as the Sears second-generation Stillson pattern by the paneled jaw carrier, the absence of external leaf springs, and the forged-in "Sears" marking. (These wrenches were also made with forged-in "Companion" brand markings.)

The Fuller version of this wrench was identical except for the markings, which typically included the KTC-Oval logo. By 1971 KTC itself was offering this model on page 20 [External Link] of its catalog, and the illustration noted a JIS "H" certification.

[KTC] Craftsman 55677 "BF" 14 Inch (350mm) Heavy-Duty Pipe Wrench

By 1978 KTC was supplying Craftsman brand pipe wrenches to Sears.

Fig. 73. Craftsman 55677 "BF" 14 Inch Heavy-Duty Pipe Wrench, with Insets for Back Side, Side View, and Marking Detail, ca. 1978 to Mid 1980s.

Fig. 73 shows a Craftsman 55677 14 inch heavy-duty pipe wrench, marked with "Craftsman" and "Heavy Duty" cast into the front, with "Extra Strong" and "Japan BF" plus the model number cast into the back.

The overall length is 12.9 inches closed and approximately 15.8 inches fully extended. The finish is plain steel and red paint.

The jaw is marked with "Drop Forged" and "BF" forged into one side and has graduated markings for the opening size (not shown).

The 1978 catalog noted that the Craftsman heavy-duty pipe wrenches were imported and described the construction as a "one piece, ductile-steel housing, frame, and handle." These were the first imported Craftsman pipe wrenches.

KTC is known to have been the manufacturer of heavy-duty pipe wrenches for the "BF" series, and the use of ductile cast iron is a characteristic of KTC's pipe wrench production.

This wrench is quite similar to the Sears 30852 "BF" Heavy-Duty Pipe Wrench, a model first offered in 1968 and still available in the late 1970s. The 1978 catalog provided the shipping weights for the two wrench series, with the 14 inch Craftsman version being 6 ounces heavier than the corresponding Sears version.

Craftsman Wrenches

1n 1969 KTC began supplying Craftsman combination wrenches for the Sears "BF" series, which were the first Craftsman-branded tools in the series.

[KTC] Craftsman "BF" 5/8 Combination Wrench

The next figure shows an early example of KTC's production for the Craftsman brand.

Fig. 74. Craftsman "BF" 5/8 Combination Wrench, with Insets for Back Side, Side View, and Marking Detail, ca. 1969.

Fig. 74 shows a Craftsman "BF" 5/8 combination wrench with raised panels, stamped with the "=Craftsman=" logo and fractional size on the front panel, with "Chrome Molybdenum" and "BF Japan" plus the fractional size on the back panel.

The shank is also marked with a forged-in "C0" code, as seen in the lower inset.

The top inset shows a side view of the wrench. Note the rounded and polished side of the open end, an extra finishing touch provided by this maker.

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

The forged-in "C0" code indicates that this wrench was produced by KTC for the Sears Craftsman brand.

The absence of a model number on this wrench suggests production before 1970. KTC's published history states that production of Craftsman combination wrenches began in 1969, suggesting that this is an early example.