| Alloy Artifacts |
Hokuyo Sangyō (北陽産業) was a maker of wrenches, pliers and other tools operating in Niigata prefecture. The company was originally a division of Sanjō Kikai Seisakusho (三条機械製作所), a maker of machinery and tools, and remained closely associated with the parent company after a 1948 spinoff.
Background information on the Japanese tool industry can be found in our page on Japanese Tool Makers.
Hokuyo Sangyō (北陽産業) was originally a division of Sanjō Kikai Seisakusho (三条機械製作所), a maker of machinery and tools, and remained closely associated with the parent company after a 1948 spinoff.
In 1948 the Hokuyo Sangyō Co. Ltd. was formed by a spinoff of the tool division of Sanjō Kikai. Among its first products were wrenches sold under the "SANKI" brand, with production by Sanjō Kikai and sales by Hokuyo Sangyō.
Since production was being provided by the parent company, the Sanjō Kikai factory was effectively the first factory for Hokuyo Sangyō.
Sanjō Kikai registered "SANKI" as a trademark in 1949.
On June 28, 1951 Sanjō Kikai received JIS certification 655 for class B4604 (adjustable wrenches), with the factory address at Yokaichi (四日市) in Sanjō City. The record for this certification can be seen in the section on the 1951 JIS Summary for Class B4604 and B4605. Sanjō Kikai was one of the first five companies to receive certification for adjustable wrenches.
On October 31, 1951 Sanjō Kikai received certification for cutting pliers at the 1310 Yokkaichi factory, probably as JIS 1016 in class B4623 (side-cutting pliers). The record for this certification can be seen in the 1952-05 Monthly Report for Classes B4623-B4625.
We haven't found any later records for a B4623 certification, suggesting that it may have been discontinued.
On June 17, 1954 Sanjō Kikai received certification 3195 for B4614 (combination pliers) at the 1310 Yokkaichi factory. The record for this certification can be seen in the 1955 JIS Summary for Class B4614.
By the late 1950s or early 1960s Sanjō Kikai was providing JIS-certified adjustable wrenches to Nissan, an example of which can be seen as the [Sanki] Nissan 250mm Adjustable Wrench.
Sanjō Kikai was listed in the 1962 Certified List but not in the 1964 Certified List, suggesting that it had relinquished its JIS certificates and had transferred tool production to Hokuyo Sangyō by 1964.
On January 13, 1964 Hokuyo Sangyō received JIS certification 9786 for class B4604 (adjustable wrenches), with the factory address at 4144 Nishi Honjoji in Sanjō City. The record for this certification can be seen in the 1964-04 Monthly Report for Class B4604. (A later report provided notes indicating a 15° offset in normal and heavy grade.)
On the same date the company also received JIS 9787 for class B4614 (combination pliers) at the same factory address. The record for this certification can be seen in the 1964-04 Monthly Report for Class B4614.
Later on September 15, 1964 the company received 364147 for class B4630 (open-end wrenches) at the Nishi Honjoji factory. The record for this certification can be seen in the Aggregated Monthly Reports for 1964-12.
The fact that Hokuyo Sangyō received JIS certification in 1964 shows that it was managing its own factory by this time.
In 1968 the company opened a new factory at the 1825 Higashi Honjoji in Sanjō City.
On August 1, 1968 Hokuyo Sangyō received JIS certification 9786 for class B4604 (adjustable wrenches) at the 1825 Higashi Honjoji factory. The record for this certification can be seen in the Aggregated Monthly Reports for 1968-11.
On the same date the company received JIS certification 9787 for class B4614 (combination pliers) at the 1825 Higashi Honjoji factory. The record for this certification can be seen in the Aggregated Monthly Reports for 1968-11.
On the same date the company received JIS certification 364147 for class B4630 (open-end wrenches) at the 1825 Higashi Honjoji factory. The record for this certification can be seen in the Aggregated Monthly Reports for 1968-11.
The JIS Certifications for August of 1968 all list the company name followed by "本社栄工場" or "Head Office Sakae Factory". (The "Sakae" name is a bit of a mystery, since it doesn't appear in the address.)
On May 29, 1969 Hokuyo Sangyō received JIS certification 369042 for class B4632 (box-end wrenches) at 1825 Higashi Honjoji. The record for this certification can be seen in the Aggregated Monthly Reports for 1969-08. (The certification for JIS 369042 was later transferred to JIS 364147.)
Hokuyo Sangyō is known to have been a contract manufacturer for KTC, based on numerous observations of KTC adjustable wrenches marked with an "SA" code or with JIS 9786, indicating production by Hokuyo Sangyō.
In addition, examples have been found of "Sears" and "Companion" brand adjustable wrenches with production characteristics that identify Hokuyo Sangyō as the maker. The Sears 12 Inch Adjustable Wrench is in an older style and appears to have been made around 1968, and the Companion "BF" 12 Inch Adjustable Wrench was probably made in 1969.
From the known examples, it appears that Sanki's production for both KTC and Sears started in the late 1960s, around the same time as the opening of Hokuyo Sangyō's factory at 1825 Higashi Honjoji. We think that the timing of these important contracts and the new factory is not at all coincidental, but rather indicates that the company had signed contracts to supply wrenches for KTC and Sears and was expanding its facilities in preparation.
Based on the opening of a new factory in 1968, we think that this year marks the start of significant production for KTC and its affiliated contracts.
Hokuyo Sangyō had been supplying adjustable wrenches to the Fuller Tool Company for a number of years, going back to the original production by Sanjō Kikai in the late 1950s. With the addition of KTC and Sears as customers, Hokuyo Sangyō became a major producer of adjustable wrenches.
By 1985 the company was operating a new factory at 7-54 Doba in Sanjō City (新潟県三条市土場７番５４号). (Google sometimes translates 土場 as "Tsuchiba" instead of "Doba".)
On December 27, 1985 Hokuyo Sangyō received JIS certification 385133 for class B4626 (water pump pliers) at the 7-54 Doba factory. The record for this certification can be seen in the Aggregated Monthly Reports for 1986-03.
On May 24, 1990 the company transferred JIS certificates 9786, 9787, 364147, and 369042 from the 1825 Higashi Honjoji factory to the 7-54 Doba factory. The records for these certifications can be seen in the Aggregated Monthly Reports for 1990-11.
The 1999 Summary listed the 7-54 Doba factory for all of the company's JIS certifications.
With the transfer of production of adjustable wrenches, pliers, open-end wrenches, and box-end wrenches to the new factory, it would appear that the old factory at 1825 Higashi Honjoji would have closed. However, in the 1999 Summary the Hokuyo Sangyō name is still followed by "Head Office Sakae Factory", the same listing used when 1825 Higashi Honjoji was the active factory.
We're not sure what this means, except possibly that other production continued at the old location and the company still considered it to be the head office factory.
By the early 1990s the "SUNKEY" brand had superseded the SANKI brand.
Sanjō Kikai (the parent company) had registered "SUNKEY" as a trademark in 1984.
In 2000 Toho Kōki relinquished its JIS certification for adjustable wrenches and began outsourcing production. Hokuyo Sangyō became one of the production partners for Toho Kōki, based on observations of "Strong HIT" wrenches marked with an "SA" code and JIS 9786.
By 2002 the Hokuyo Sangyō website was no longer available and the company is assumed to have closed.
![[Japanese Trademark 25-12124]](Photos/tools/scans/japan_trademark_25-12124_sanki_cropped.jpg)
Fig. 1 shows the announcement for Japanese trademark 25-12124, issued to Sanjō Kikai on Showa 25.8.11 or August 11, 1949.
The illustration shows the text "SANKI" in a slanted font.
Sanjō Kikai received JIS certification for classes B4604 (adjustable wrenches) and B4614 (combination pliers).
View Company History with Factories for Sanjō Kikai.
View JIS Certification Events for Sanjō Kikai.
Hokuyo Sangyō is known to have received JIS certification for classes B4604 (adjustable wrenches), B4614 (combination pliers), B4626 (water pump pliers), B4630 (open-end wrenches), and B4632 (box-end wrenches).
Background information on the JIS program can be found in our article on Japanese Industrial Standards.
Tools made by Sanjō Kikai were typically marked with the "Sanki" brand and the 3-Ki-Circle logo.
Later tools made by Hokuyo Sangyō were typically marked with the "Sanki" or "Sunkey" brands.
![[3-Ki-Circle Logo]](Photos/tools/scans/sanki_3_ki_logo.jpg){kind=logo}
Fig. 2 shows the 3-Ki-Circle logo as it was presented in a 1962 Japanese industry directory.
The logo was derived from the first syllables of Sanjō Kikai and is composed of three Katakana キ ("ki") characters arranged in a circle. ("San" is three in Japanese.)
Photographs and observations of particular tools are based on items in the Alloy Artifacts Collection.
| Catalog | Year | Notes |
|---|---|---|
| Energy Tools | 1989 | Catalog in Japanese. 88 pages.
Available for Download [External Link] from ITCL. |
| Energy Tools | 1990 | Catalog in Japanese. 38 pages.
Available for Download [External Link] from ITCL. Lists JIS B4623, B4625, B4631, and B4635 pliers from Maruto Hasegawa. |
![[Sanki AS-600 6-Piece Open-End Wrench Set]](Photos/tools/sanki_oe_wrench_set_jis_6pc_f_cropped_inset_w2048.jpg)
Fig. 3A shows a Sanki 6-piece open-end wrench set in its metal holder, embossed with "SANKI" and the JIS-Circle logo on the front.
The wrench sizes are 8x9mm, 10x12mm, 12x14mm, 14x17mm, 17x19mm, and 21x23mm.
All of the wrenches are marked with "Sanki" and the JIS-Circle logo forged into the front, with "S" and "Drop Forged" forged into the back.
The JIS symbol refers to JIS 364147, first received by the company in 1964.
The set is not marked with a model number, but was identified as the AS-600 set by a listing in the 1989 catalog. Sanki also offered similar sets with different selection of sizes, including fractional inch sizes.
![[Sanki 21x23mm Open-End Wrench]](Photos/tools/sanki_oe2123mm_wrench_jis_6pc_f_cropped_inset_w2048.jpg)
Fig. 3B shows a Sanki 21x23mm open-end wrench, marked with the JIS-Circle logo and "SANKI" forged into the front, with "S" and "Drop Forged" forged into the back side.
The wrench is also marked with a "0AH" production code forged into the back side at the right.
The overall length is 8.8 inches, and the finish is chrome plating.
The JIS symbol refers to JIS 364147, first received by the company in 1964.
The "S" marking is a reference to the "spear-type" elongated jaws, a popular style in Japan.
This wrench was acquired as part of an AS-600 6-piece wrench set in a metal clip.
![[Early Sanki 250mm Adjustable Wrench]](Photos/tools/sanki_adj_250mm_wrench_jisn_f_cropped_inset3_w2048.jpg)
Fig. 4A shows an early Sanki 250mm adjustable wrench, marked with "SANKI" and the 3-Ki-Circle logo forged into the front, with "Specially Selected Steel" and the JIS-Circle logo forged into the back side.
The wrench is also marked with an "N" code forged into the front, an indication of JIS "Normal" grade.
The center inset provides a close-up of the jaw construction. Note the angled transition at the corner of the fixed jaw and the corresponding angled inset on the movable jaw.
The overall length is 10.2 inches, and the maximum jaw opening is 1.2 inches.
The finish is chrome plating, with extensive losses due to wear and rust.
The wrench was extremely dirty and rusty when we acquired it and had obviously been subjected to hard use and abuse. As can be seen in the photo, the handle is slightly bent, and the stud securing the worm gear has even been replaced with a machine screw!
We gave the wrench an overnight soak in our electrolytic "spa" (see the section on Electrolytic Derusting for details) and then disassembled it for a thorough cleaning. It cleaned up nicely and now operates smoothly and is fully functional.
This wrench has a very distinctive style with its 15° jaw offset, constant width handle, drilled hanging hole, and open panel sloping up to the head. We acquired it specifically as an "anchor", in order to show the continuity of early production by Sanjō Kikai with later contract production for Fuller and Sears. Examples of wrenches in this same style can be seen as the:
The last wrench in the list was made around 1968, and shortly after this it appears that Sanki (Hokuyo Sangyō at that time) switched to making wrenches with tapered handles and a ridge around the hanging hole. Thus this style of wrench was likely produced from the early 1950s until 1968.
![[Sanki 250mm Adjustable Wrench]](Photos/tools/sanki_adj_250mm_wrench_cv_jis_japan_f_cropped_inset4_w2048.jpg)
Fig. 4 shows a Sanki 250mm adjustable wrench, marked with "SANKI" and "15° Type" forged into the front, with the JIS-Circle+H logo and "Chrome Vanadium" forged into the back side.
The back side also has a forged-in "JAPAN" marking near the hanging hole, with the text perpendicular to the axis of the wrench.
The center inset provides a close-up of the jaw construction. Note the angled transition at the corner of the fixed jaw, and the corresponding angled inset on the movable jaw.
The overall length is 10.1 inches, and the maximum jaw opening is 1.2 inches. The finish is chrome plating.
The bottom inset shows an unexpected detail: the threaded pin securing the worm gear has a crosspoint opening! Most adjustable wrenches use a conventional slotted pin, so this detail may assist with identifying Sanki production. Another detail to note is that the pin is threaded on the inside end.
The 15° jaw offset angle of this wrench is a less common design choice, and Sanki was one of the few companies to offer wrenches of this type. As a practical matter there are few situations where the jaw offset would really matter, although it's possible that a hexagonal nut in a tight position might be easier to turn with this wrench.
The company also made the more common 23° offset wrenches.
In 1954 Sanjō Kikai received JIS certificate 3195 for combination pliers (class B4614), with the address listed as 1310 Yokkaichi in Sanjō City. The parent company continued making pliers until 1964, when Hokuyo Sangyō received JIS certificate 9787 for class B4614.
![[Sanki 7 Inch Thin-Nose Combination Pliers]](Photos/tools/sanki_pliers_7in_combo_thin_f_cropped_inset3_w2048.jpg)
Fig. 5 shows a pair of Sanki 7 inch thin-nose combination pliers, marked with the 3-Ki-Circle logo and "SANKI" forged into the handle.
The top inset shows a side view of the pliers, illustrating the thin jaws and the unusual fan-like gripping pattern on the handles.
The overall length is 7.1 inches.
The finish is plain steel, with possible traces of cadmium plating.
In later years Sanki sourced fixed-pivot pliers from Maruto Hasegawa, a makor of pliers in Niigata prefecture.
![[Sanki 125mm Diagonal Cutting Pliers]](Photos/tools/sanki_pliers_125mm_diag_alloy_jis_mh_f2_cropped_inset4_w2048.jpg)
Fig. 5B shows a pair of Sanki 125mm diagonal cutting pliers, stamped with "Sanki" and "Alloy Steel" around the pivot, with the JIS-Circle+H logo in the center.
The pliers are also stamped with an "MH 84M" code on the back.
The overall length is 5.2 inches, and the finish is plain steel with red plastic hand grips.
The "MH" code indicates production by Maruto Hasegawa.
Sanjō Kikai was a supplier of adjustable wrenches for Nissan, with production probably beginning in the late 1950s or early 1960s. The wrenches were very similar to the Sanki 250mm Adjustable Wrench shown earlier but with the Nissan logo on the front.
Currently we have observed only wrenches in the 250mm size, and the wrenches have all been marked for JIS "H" grade.
![[Sanki Nissan 250mm Adjustable Wrench]](Photos/tools/nissan_adj_250mm_wrench_jish_sanki_3f_f_cropped_inset3_w2048.jpg)
Fig. 6A shows a Nissan 250mm adjustable wrench, marked with the Nissan logo and a "3F" production code forged into the front, with "Specially Alloy Steel" and the 3-Ki-Circle logo forged into the back.
The wrench is also marked with "H" and the JIS-Circle logo forged into the back at the left.
The lower inset shows a close-up of the open jaws, illustrating the angled transition at the corner of the fixed jaw and the corresponding angled cutaway of the movable jaw.
The overall length is 10.2 inches and the maximum opening is 1.2 inches.
The finish is nickel plating with polished faces, with losses due to wear and rust.
We disassembled the wrench for cleaning and verified that the pin securing the worm gear is threaded on the inside end.
The 3-Ki-Circle logo indicates production by Sanjō Kikai, but even without the logo, Sanjō Kikai can be recognized as the maker by the distinctive construction features of the wrench. Note in particular the constant width of the handle, the small plain hanging hole, the 15° jaw offset angle, and the way the handle panel opens and slopes towards the head.
The JIS-Circle logo refers to JIS 655, first received by the company in 1951. The "H" marking indicates JIS "Heavy" grade, although we currently don't have a record of the company receiving JIS "H" certification. Note that the 3-Ki-Circle logo is acting as the JIS ID code.
This wrench is very similar to the Sanki 250mm Adjustable Wrench displayed in an earlier figure. One important difference is that this wrench is marked for JIS "H" grade instead of "N" grade, and the marking on the back has changed from "Specially Selected Steel" to the (grammatically challenged) "Specially Alloy Steel".
![[Sanki Nissan 250mm Adjustable Wrench]](Photos/tools/nissan_adj_250mm_wrench_jish_sanki_f_cropped_inset3_w2048.jpg)
Fig. 6B shows another similar Nissan 250mm adjustable wrench, marked with the Nissan logo and a "4D" production code forged into the front, with "Specially Alloy Steel" forged into the back.
The back side is also marked with "H" and the JIS-Circle logo on the left and the 3-Ki-Circle logo on the right.
The lower inset shows a close-up of the open jaws, illustrating the angled transition at the corner of the fixed jaw and the corresponding angled cutaway of the movable jaw.
The overall length is 10.0 inches and the maximum opening is 1.2 inches.
The finish is nickel plating with polished faces, with losses due to wear, rust, and welding.
The 3-Ki-Circle logo indicates production by Sanjō Kikai. This wrench is very similar to the previous figure and most of our comments there apply here as well.
This wrench has seen extensive use and abuse and was apparently owned by a welder, as the end of the handle has been flattened by welding, and the wrench has welding splatter is several places.
In addition, the pin securing the worm gear has also been welded in place for a really permanent installation — perhaps the pin came loose one too many times? If you look closely at the lower inset you can seen a welding bead where the hole for the pin used to be.
Hokuyo Sangyō was a major supplier to the Fuller Tool Company, an American tool company with a major Japanese import business.
Production for Fuller probably began around 1958 with an early series of "Thin Pattern" wrenches, a time when production was still under the control of the parent company Sanjō Kikai.
The next two figures show examples of early Fuller "Thin Pattern" adjustable wrenches made by Sanki.
![[Early Fuller SANKI 6 Inch Thin-Pattern Adjustable Wrench]](Photos/tools/fuller_adj_6in_wrench_thin_cas_sanki_japan_f_cropped_inset3_w2048.jpg)
Fig. 7A shows an early Fuller 6 inch thin-pattern adjustable wrench, marked with "Fuller" and "Drop Forged" forged into the front, with "Thin Pattern" and "Chrome Alloy Steel" forged into the back.
The shank is also marked with "SANKI" forged along a curved arc near the hanging hole, with "Japan" along a curved arc on the back side.
The lower inset shows a close-up of the open jaws, illustrating the angled transition at the corner of the fixed jaw and the corresponding angled cutaway of the movable jaw.
The overall length is 6.3 inches and the maximum opening is 0.9 inches. The finish is chrome plating with polished faces.
We removed the pin securing the worm gear and noted that it is threaded on the inside end.
Please see the comments following the next figure for additional information applying to both wrenches.
![[Early Fuller SANKI 10 Inch Thin-Pattern Adjustable Wrench]](Photos/tools/fuller_adj_10in_wrench_thin_cas_sanki_japan_f_cropped_inset3_w2048.jpg)
Fig. 7 shows an early Fuller 10 inch thin-pattern adjustable wrench, marked with "Fuller" and "Drop Forged" forged into the front, with "Thin Pattern" and "Chrome Alloy Steel" forged into the back.
The shank is also marked with "SANKI" forged along a curved arc near the hanging hole, with "Japan" along a curved arc on the back side.
The lower inset shows a close-up of the open jaws, illustrating the angled transition at the corner of the fixed jaw and the corresponding angled cutaway of the movable jaw.
The overall length is 10.2 inches and the maximum opening is 1.2 inches. The finish is chrome plating with polished faces.
We removed the pin securing the worm gear and noted that it is threaded on the inside end.
The markings on this wrench suggest an early production date. The "Thin Pattern" marking is rare for Fuller wrenches and suggests a contrast with a "thick" pattern, presumably a carbon steel (or non-alloy) wrench. We haven't seen a non-alloy Fuller adjustable wrench, but "Thin Pattern" would be a reminder that alloy-steel wrenches are thinner and lighter.
Another detail to note is that the wrench is not marked with "No. <size>", the "model number" marking found on most other Fuller wrenches.
Some readers may have already noticed another detail worth mentioning, which is that this wrench has a 15° jaw offset angle, instead of the more common 22.5° offset. The 15° offset was Sanki's preferred construction during the 1950s and 1960s.
The early markings suggest a production date in the late 1950s to early 1960s. During that period the "SANKI" marking would indicate production by Sanjō Kikai Seisakusho, the parent company of Hokuyo Sangyō. Sanjō Kikai turned over production of "SANKI" wrenches to Hokuyo Sangyō in 1964.
![[Fuller No. 10 SANKI 10 Inch Adjustable Wrench]](Photos/tools/fuller_adj_no10_wrench_ca_plainhole_sanki_japan_f2_cropped_inset4_w2048.jpg)
Fig. 8 shows a Fuller No. 10 10 inch adjustable wrench, marked with "Fuller" and "Chrome Alloy No. 10" forged into the front, and with "Full Drop Forged" and "JAPAN" forged into the back side.
The shank is also marked with "SANKI" forged along a curved arc near the hanging hole, as seen in the small upper inset.
The lower inset shows a close-up of the jaw construction, illustrating the angled transition to the fixed jaw and the angled inset on the movable jaw.
The overall length is 10.2 inches, and the maximum opening is 1.1 inches. The finish is chrome plating with polished faces.
The "SANKI" marking indicates production by Hokuyo Sangyō or possibly Sanjō Kikai, depending on the date.
One construction detail to note is that the pin securing the worm gear is threaded on the inside end, a characteristic of Hokuyo Sangyō production.
Another important detail is that there is no ridge round the hanging hole, a less common design choice that can also be found on KTC wrenches prior to the 1970s. Notice though that the diameter of Sanki's hole is substantially smaller than what would fit within the outer ridge of the shank.
In contrast, KTC's plain hanging hole is larger and goes close to the edge of the outer ridge, as can be seen in the Fuller No. 12 "KTC" Adjustable Wrench.
![[Fuller No. 6 SANKI 6 Inch Adjustable Wrench]](Photos/tools/fuller_adj_no6_wrench_ca_sanki_f_cropped_inset4_w2048.jpg)
Fig. 9 shows a Fuller No. 6 6 inch adjustable wrench, marked with "Fuller" and "Chrome Alloy No. 6" forged into the front, and with "Full Drop Forged" forged into the back side.
The shank is also marked with "SANKI" forged into the front, with "JAPAN" forged into the back side.
The lower inset shows a close-up of the open jaws, illustrating the angled transition at the corner of the fixed jaw and the angled inset at the corner 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.
The "SANKI" marking indicates production by Hokuyo Sangyō.
We were able to remove the pin securing the worm gear and verified that it is threaded on the inside end.
In the late 1960s Hokuyo Sangyō became a major production partner for KTC and may have supplied the majority of KTC-branded adjustable wrenches in the 1970s to 1980s time frame.
![[KTC 300mm Adjustable Wrench]](Photos/tools/ktc_adj_300mm_wrench_ktc-oval_jish_ridge_9786_f_cropped_inset4_w2048.jpg)
Fig. 10 shows a KTC 300mm adjustable wrench, marked with the KTC-Oval logo and "Kyoto Tool" plus the JIS-Circle+H logo forged into the front, with "KTC, Alloy Steel" and "Japan" forged into the back.
The wrench is also marked with a "9786" code forged into the front below the "H", with a "49 SA" code forged into the back.
The top inset shows a side view of the wrench, illustrating the relatively thin head made possible by alloy steel.
The middle 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 "spear type" jaw outline.
The small bottom inset shows a close-up of the pin securing the worm gear, illustrating the cross-point drive end of the pin.
Note that the hanging hole is fully enclosed by a ridge.
This wrench is very similar to the KTC 300mm Adjustable Wrench displayed in our article on KTC, and at first glance the two wrenches appear identical. But a small difference in the markings allows us to identify this wrench as contract production.
The "9786" marking on the front is the JIS certificate for Hokuyo Sangyō, indicating that this wrench was made for KTC by Sanki. (The "SA" marking is the JIS ID code for Sanki, and some contract production for KTC carries only the "SA" marking on the back.)
Apart from the subtle differences in markings, there are also subtle differences in construction. For Sanki the pin securing the worm gear is threaded on the inside end, but the third-generation wrenches from KTC switched to having the pin threaded on the outside end.
In addition, the pin on this wrench has a cross-point drive end, a feature known only on later Sanki wrenches. This detail suggests production in the 1980s.
Hokuyo Sangyō was a major supplier of adjustable wrenches to both Fuller and KTC, and both of these companies were working closely to supply tools for the Sears Roebuck "BF" series.
Thus it's not surprising that Hokuyo Sangyō also became a supplier of adjustable wrenches to Sears.
![[Sears 30873 12 Inch Adjustable Wrench]](Photos/tools/sears_adj_12in_wrench_cas_ph_angled_f_cropped_inset3_w2048.jpg)
Fig. 11 shows a Sears [30873] 12 inch adjustable wrench, marked with "Sears" and "Chrome Alloy Steel" forged into the front, with "Full Drop Forged" and "Japan" forged into the back.
The lower inset shows a close-up of the fully open jaws. Note the angled transition at the corner of the fixed jaw, with a corresponding angled cutaway on the movable jaw.
The overall length is 11.9 inches and the maximum opening is 1.4 inches. 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 30873.
We removed the pin securing the worm gear and confirmed that it is threaded on the inside end.
This wrench has been identified as production by Hokuyo Sangyō based on the close resemblance to the Fuller No. 10 "SANKI" 10 Inch Adjustable Wrench. Note in particular the relatively small plain hanging hole and the constant width of the handle, which are fairly uncommon production quirks known to have been used by Sanki.
In addition, the wrench uses an angled transition at the fixed jaw and inside threads on the pin, both standard production characteristics for Sanki.
Note that the wrench is missing the forged-in "BF" marking typically placed near "Japan", an omission that suggests that this wrench was among the first made by Sanki for Sears.
The absence of a model number marking suggests production before 1970, and we believe a 1968 production date is most likely.
![[Companion 30873 BF 12 Inch Adjustable Wrench]](Photos/tools/companion_adj_12in_wrench_ca_bf_japan_f_cropped_inset4_w2048.jpg)
Fig. 12 shows a Companion "BF" 12 inch adjustable wrench, marked with "Companion" and "Chrome Alloy" forged into the front, with "Full Drop Forged" and "Japan BF" forged into the back.
The lower inset shows a close-up of the fully open jaws, illustrating the angled transition at the corner of the fixed jaw and the corresponding angled inset 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.
The wrench is not marked with a model number, but based on the catalogs would have been model 30873.
We disassembled the wrench for cleaning and observed that the pin holding the worm gear is threaded on the inside end.
The absence of a model number marking suggests production before 1970, and the "Companion" marking refines this to the late 1960s. But see the discussion below for a further refinement to the production date estimate.
This wrench has been identified as production by Hokuyo Sangyō ("Sanki") based on the close resemblance to the Sears 30874 6 Inch Adjustable Wrench. Important details include the "Chrome Alloy" marking, the use of an angled transition at the fixed jaw, and the ridge around the hanging hole.
In the late 1960s KTC was also a supplier of adjustable wrenches to Sears, but at that time was using a rounded transition at the fixed jaw and a plain hanging hole.
An interesting comparison can be made between this wrench and another wrench made by Sanki, the Sears [30873] "Japan" 12 Inch Adjustable Wrench. The Sears wrench is made in a quirky style with a constant-width handle and a relatively small plain hanging hole, whereas the present wrench has a more standard handle tapering wider towards the end and with a ridge around the hanging hole.
We believe the Sears brand wrench was made when Sanki was just beginning production for Sears, and that it was reusing its own earlier designs to make the forging dies for Sears, and even forgot to add the "BF" code.
In contrast, the present example is close to the style observed for the 1970s and beyond. From these arguments we can conclude that this Companion wrench was made after the Sears wrench, making 1969 the most likely production year.
![[Sears 30874 BF 6 Inch Adjustable Wrench]](Photos/tools/sears_adj_30874_wrench_ca_bf_japan_f_cropped_inset4_w2048.jpg)
Fig. 13 shows a Sears 30874 6 inch adjustable wrench, marked with "Sears" and "Chrome Alloy" forged into the front, with "Forged No. 30874" and "BF Japan" forged into the back.
The lower inset shows a close-up of the fully open jaws, illustrating the angled transition at the corner of the fixed jaw and the corresponding angled inset of the movable jaw.
Note also that the tailpiece narrows rapidly to the cylindrical section of the movable jaw.
The overall length is 6.1 inches, and the maximum jaw opening is 0.8 inches. The finish is chrome plating with polished faces.
The 30874 model number indicates production in 1972 or later. (Earlier catalogs listed the Sears 6 inch adjustable wrenches as model 30870.)
A comparison of this wrench with the Fuller No. 6 "SANKI" 6 Inch Adjustable Wrench found that the tools are nearly identical in construction and dimensions. Based on this comparison, we are confident that this wrench was made by Hokuyo Sangyō.
In later years Hokuyo Sangyō began production of JIS-certified adjustable wrenches for Toho Kōki when the latter company decided to cease internal production. Examples of "Strong HIT" wrenches have been observed marked with Sanki's JIS 9876 certification.
| Alloy Artifacts Home | Text and Photographs Copyright © 2005-2025 Alloy Artifacts | Site Index |