Japanese Tool Makers

Table of Contents

Introduction

Japan has a long history of fine craftsmanship in tool making going back hundreds of years. Although the country was late to industrialize, after opening up to the West in the 1870s Japan rapidly built an industrial economy, with special strength in heavy industries such as shipbuilding. In the post-war era Japan developed an export-oriented economy and became a dominant supplier in areas such as cameras, consumer electronics, automobiles, and robots.

As would be expected from these industrial capabilities, Japanese toolmakers can produce tools that rank with the finest available anywhere. However, some Japanese tools are not readily available outside their home market, and the examples available here at Alloy Artifacts are generally limited to those produced for export to the U.S. market. For this reason our site cannot do justice to the full range of Japanese toolmaking.

When looking through the examples here, keep in mind that most of these tools are much more recent than the tools in other parts of this site. Our oldest Japanese tools (for the Allenite brand) barely go back to the 1950s, and many of the others are probably from the 1970s or later.

Lost in Translation

Most of the companies listed here maintain a website, some of which offer an English section, but otherwise in Japanese only. English speakers can make use of Google Translate or other machine translations, but the language and cultural differences will inevitably lead to some unexpected or confusing results.

Spanners and more. Japan's early industrial development was heavily influenced by Great Britain, and some British terms are still in wide use. For example, open-end wrenches are called "spanners" in Japan, and this term may come up in translations. Most of our readers are probably already familiar with spanners, and if we asked for a ring spanner, most would hand us the box-end wrench.

But how about an eyeglasses wrench? In Japan a box-end wrench is めがねレンチ ("megane renchi"), literally "eyeglasses wrench". Depending on the context available, some machine translations will occasionally spit out an eyeglasses wrench.

Monkey Wrenches. Another unexpected term is the usage of "monkey wrench". In America a monkey wrench usually means a wrench with jaws at right angles to the shank, with the lower jaw moving parallel to the shank. But in Japan the term "monkey wrench" is a synonym for a Crescent-style adjustable wrench.

Trading Companies. The histories of Japanese tool companies often mention the establishment of a "trading company". In America the term "trading company" usually means a financial company trading stocks and bonds, or perhaps agricultural commodities like corn and soybeans.

The issue comes down to the translation for kanji 商社 (shōsha) in the context of tools, which our CWC Japanese source says is a distributor, but which Google Translate renders as "trading company". For now we will call this a distributor.

We're currently trying to clarify whether the tool companies have set up an actual distributor operation that handles tools from other companies as well, or if it's more like a sales and marketing organization for their own products.

Company, Ltd. Company histories may sometimes mention a reorganization leading to a name followed by "Company, Ltd.", which is a translation for 株式会社 ("kabushikigaisha"), meaning a public company trading on the stock market. (Written Japanese actually includes the special character ㈱ as an abbreviation for these four kanji, formed by taking the first character and putting parentheses around it.)

On this site we generally don't care whether companies are public or private, unless it affects the markings on their tools, and so we will often drop the "Company, Ltd." for brevity.

A Note on the "Japan" Marking

Under Japanese law products made for export must be marked "Japan" to show the country of origin, but this marking is optional for domestic production. This means that if a Japanese tool is found in the US without a "Japan" marking, it was originally made for domestic use and then accidentally or informally exported later.

References and Resources

Photographs and observations of particular tools are based on items in the Alloy Artifacts collection.

CWC

Historical information on Japanese tool companies can be found (in Japanese) at the コンビネーションレンチ･コレクション Combination Wrench Collection [External Link] web site. We will refer to this reference as "CWC" in the text.

Japan Institute of Standards

No, the Japan Institute of Standards doesn't make tools, at least to our knowledge. But it does set standards for quality in hand tools, and companies whose tools meet these standards are allowed to mark the tools with a special symbol.

Testing Standards

JIS testing has different standards for different types of tools, and a company that makes many kinds of tools would need to pass a number of tests in order to offer JIS certification for their entire line. The JIS standards evolved over time as new standards were enacted or modified, and some standards were discontinued in the process.

In general the standards for hand tools are expressed as a JIS class, consisting of a "B" prefix followed by a four-digit number of the form B46xx.

The table below shows the JIS classes relevant to the tools of interest at Alloy Artifacts, and the "Notes" column includes a link to the formal definition for the class.

As might be expected, testing standards have been revised over the years, with the result that sometimes earlier tests are not directly comparable with later tests.

For example, initially adjustable wrenches were split into two classes based on the jaw offset angle, with 15 degree offsets in B4604 and 23 degree offsets in B4605. The standard was changed in 1954 and class B4605 was folded into B4604.

As another example, socket tools were originally placed in classes B4636 to B4641 based on the functional type, but a 1998 revision placed all socket tools into revised classes B3636-1 or B4636-2 based on the drive size. A side effect of the 1998 revision was that some prior results apparently couldn't be classified into drive sizes and were instead lumped into an odd 00225 class.

JIS Suffixes

Sometimes a JIS symbol will be followed by a letter code, of which "H" appears to be most common in our examples, but "N", "P", or "S" may also appear.

We don't have all of the details for these suffixes, but the "N" and "H" codes apply to certain JIS standards (such as B4604 and B4630) that have been split into a Normal/Ordinary class and a Heavy-Duty/Strong class. Presumably this means that additional (or more difficult) tests had to be passed to be able to display the "H" suffix.

The split into JIS-N and JIS-H occurred around 1955, and in some cases the absence of a suffix may provide information on the manufacturing date. The establishment of the JIS-H class may have been motivated by the increased use of alloy steel during the early 1950s.

The "S" code appears to apply only to standard B4630 (open-end wrenches) and designates a "spear type" style of wrench.

The "P" code appears to apply only to adjustable wrenches (B4604) and indicates a partially forged product, presumably a wrench with a malleable iron body and a forged moveable jaw. (This would seem to apply to pipe wrenches as well.)

From these brief descriptions it should be apparent that the suffixes represent a sub-class of the associated product class. Thus if we ask how the suffix qualifications should be reported, to us the the most logical approach would have been to list the qualifying suffixes after the class. For example, if a company passed the tests for open-end wrenches in normal and strong grades, the certification could be reported as class "B4630 NH"

What was done instead was to add some phrases in Japanese to a "notes" field listing various attributes of the product. The table below shows the phrases typically used to denote each suffix.

(The opposite of partial forging was 全鍛造品 or "fully forged product".)

In order to determine whether any suffixes apply to a test, you have to scan the notes field for any of these particular phrases and then add the indicated suffix. And to make matters more difficult, some of the JIS summary reports omitted the "notes" field! 😢

Test Administration

The Japan Institute of Standards defines the test standards, but the actual administration of JIS certification tests is handled by a different organization.

Initially the certification tests were administered by MITI, the government trade ministry. MITI handled test administration from its beginning in 1951 up through 1961.

In 1962 administrative responsiblility passed to the JSA, and then in 2005 the JQA took over responsibility. The latter change coincided with the change to a new JIS symbol, and tools marked with the new symbol will sometimes be marked "JQA" as well.

JIS certification involves more than just testing some tools, as it applies to the entire factory at a particular location. In some cases companies were required to be re-certified after simply moving their office functions!

JIS Numbers

If a company passes the required tests, it receives a certificate with an assigned number, and is then allowed to display that number as proof of certification.

When JIS testing began in the early 1950s the certificate numbers were assigned sequentially, making it possible to estimate a test date by the value of the number.

The numbering system changed in April of 1964 when responsibility for testing and issuing certificates was handed out to nine separate regional offices of MITI. The new numbers had six digits, with the first digit signifying the office as follows.

1. Hokkaido
2. Tohoku
3. Kanto (including Tokyo and Niigata)
4. Chubo
5. Kinki (including Osaka and Kyoto)
6. Chugoku
7. Shikoku
8. Kyushu
9. Okinawa

The second and third digits of the number specify the calendar year (in the Western calendar!) when the certificate number was first issued. The last three digits were then sequential, but only within the region.

As part of the new numbering scheme, tests typically applied to multiple classes of tools instead of just a single class. For example, classes B4630 (open-end wrenches), B4632 (box-end wrenches), and B4651 (combination wrenches) were grouped together for testing purposes. Companies would then receive a certificate for one or more of the classes in the group.

The numbering changed again in 2005 when the JQA took over JIS testing in 2005, and numbers issued after this time will have a "JQ" prefix.

Compliance with Standard

The JIS standard appears to include mechanisms to ensure compliance, in the sense of ensuring that any tool with a JIS marking was made in a factory certified for production of that type of tool.

ID Marks

Companies that have a JIS certification are expected to mark their tools with the company's own brands and forge marks, and periodic publications provide a list of factories with JIS certifications.

Our original inference was that every company must have provided information on its brand markings and symbols at the time of certification. However, we were wrong — the JIS certification process does not capture the ID marks used by a company, and instead these marks are expected to be "well known" by the industry.

Outsourced Production. The situation becomes more complicated in the case of outsourced or contract production. Suppose that company A has JIS certification itself, but wishes to have company B make a certain tool, and that the tool will be marked with company A's brand.

In order for the tool to carry the JIS marking, company B must be certified to produce that type of tool, and in addition company B must add its own identifying mark near the JIS symbol, so that the JIS certification can be traced to company B.

The net result of these compliance measures is that (in our understanding) there should be no anonymous tools with JIS markings — every tool with a JIS symbol must be traceable to a particular factory. A corollary of this is that companies with multiple factories would need to have a distinct marking symbol for each factory.

We hope to discover the identifying marks used by the companies listed here, and will document the marks in the "Tool Identification" section for each company.

Relinquishment of Certification

Companies may be required to relinquish their JIS certification in the event of a bankruptcy or other business interruptions. [Editor's note: would this include fires and earthquakes?] The logic here seems to be that if the company's management or procedures have been disrupted, they may no longer be able to ensure the quality control necessary for production.

In such cases, a company might wish to temporarily outsource production while it tries to recover from the problem, and the notes pertaining to JIS markings for outsourced production in the previous section would apply.

Tool Identification

Tools that have passed the relevant JIS standards are allowed to include a special marking, as noted below.

Fig. 1 shows the JIS Unicode symbol U+3004 resembling "JIS" in a circle, read from top to bottom and right to left.

We will refer to this symbol as the JIS-Circle logo in the text. This is actually the older version of the JIS symbol and was in use from the 1950s until 2008.

The newer JIS symbol was phased in beginning in 2005 and consists of the text "JIS" with the hook of the "J" extended to a circle. It is not yet available as a Unicode entity.

JIS-Circle Logo

Fig. 2. JIS-Circle Logo.

Fig. 2 shows the JIS-Circle logo as found forged into a tool.

The JIS-Circle mark is stamped on or forged into a tool that has passed the JIS quality standards.

JIS Queries

The CWC Japanese website is currently doing historical research on JIS certifications, including reconstruction of lost records for the early (1951-1961) era. We think this information is important for understanding the Japanese tool industry, and as a result are providing a database of JIS certification data as it becomes available.

Currently the project is still in development and the data is incomplete, but the information we have is at least useful as a "proof-of-concept".

The links below will provide some "canned" reports to show the type of information available in the database.

• Company Histories with Factory Locations
• List of Factories by Successor Company
• JIS Certification Events by Date
• JIS Certification Events by Successor Company
• JIS Certification Events for Class B4604

Free-Form Search

We've put together an experimental free-form query for JIS events that allows you to search the JIS database for any combination of company name, ID mark, JIS number, JIS class, or JIS super-class. You can enter a search in the box below:

The results of the query will show the JIS events (if any) that match all of the input keywords. For example, entering "3064" would show the JIS events having 3064 as the JIS number, and entering "B4604" would show all JIS events for class B4604 (adjustable wrenches).

A few rules for the search to keep in mind:

• A search consists of one or more keywords ("tokens") separated by spaces.
• The search is case-insensitive.
• The search generates a report of the JIS events matching all of the keywords.
• JIS numbers should be entered as a string of digits, with a "JQ" prefix for new numbers.
• JIS classes for tools are in the form B46xx, such as B4604 or B4630.
• JIS super-classes for tools are in the form B0xx, such as B010 or B027. The product categories "Wrenches", "Pliers", and "Sockets" are also treated as super-classes.
• Company names can be entered in English or Japanese, and only part of the name is required.
• A name spanning multiple words can be joined by an underscore (_) to make a single token.

Certain ID marks with special graphics have a two-character abbreviation in the database, in particular I-Circle (I○), I-Diamond (I◇), and 3-Blocks (▮▮).

Please try out the new JIS search facility, and let us know if you find any problems!

JIS Certification Reports

We have added a "JIS Certification History" section to the company articles for companies known to have passed the certification tests, and these sections include a link to generate a report of the certifications for the company.

We hope that this will eventually prove useful for estimating the production dates of some tools.

JIS Resources

The following archived links have JIS information (in Japanese).

• JIS Tests [External Link]
• JIS Classes [External Link]

Aiba Sangyō

The company was founded in 1935 by Takejiro Aiba (相場竹治郎) as the Aiba Copper and Iron Shop (相場銅鉄店) and operated in the scrap metals industry.

By 1945 the company had become a steel wholesaler.

Formation of Aiba Sangyō

In 1963 the company established the Aiba Sangyō Co., Ltd. (相場産業) under president Tetsuo Aiba (相場鉄夫). The company began manufacturing agricultural equipment and wrenches, which were sold under the "ABC" brand.

JIS Certification

In 1984 the company received JIS certificate 384052 for class B4632 (box-end wrenches). The record for this certification can be seen in the 1999 JIS Summary for Super-Class B027.

In 1988 the company began forging titanium alloys and produced titanium wrenches.

The RUNWELL Brand

In 2011 the company developed the RUNWELL brand for bicycle parts and tools and entered the bike racing industry.

Continuing Operations

The company remains in business today and more information can be found at the Aiba Sangyō [External Link] website.

JIS Certification History

In 1984 Aiba Sangyō received JIS certification in class B4632.

The factory location is 1691-5 Kaneko Shinden Otsu, Sanjo City, Niigata Prefecture.

View Company History with Factories for Aiba Sangyō.

View JIS Certification Events for Aiba Sangyō.

AIGO Kōgyō

AIGO Kōgyō (相伍工業) was a maker of wrenches and other tools operating in Niigata Prefecture. The company was founded in 1928 and closed in 2011.

The company was initially founded in 1928 by Gosaburo Aida (相田五三郎) as the Aida Iron Works, and manufactured forged agricultural tools at a factory in Sanjo City, Niigata prefecture.

After the war ended, in 1945 the company became the AIGO Noki Seisakusho (AIGO Agricultural Machinery Works). The name "AIGO" was formed from the first syllables of the founder's name, so that AIda GOsaburo became AIGO.

In 1950 company was listed on the stock market.

In 1958 the company began to make power tools, and in 1960 the name was changed to the AIGO Kōgyō Company, Ltd.

JIS Certification

On February 1, 1966 the company received JIS certificate 366008 for class B4630 (open-end wrenches). The record for this certification can be seen in the 1967 Certified List for Class B4630.

In 1967 the company received JIS certification for "H" (heavy-duty) and "S" (spear shaped) wrenches, but due to data limitations we don't have a record of this.

Contract Production

In addition to making tools for its own brand, AIGO did extensive contract production for other companies, notably for the "Truecraft" brand of the Daido Corporation U.S.A., as well as many other U.S. brands.

AIGO typically marked its wrenches with a distinctive two-line manufacturer's code, with one or two alphabetic characters on the top line and two numbers on the lower line. The presence of a code in this form provides reasonably certain identification of AIGO as the maker of a tool.

AIGO supplied Truecraft combination wrenches probably beginning in the mid 1960s, and flex-box combination wrenches beginning in 1968. Production of Truecraft flex-box combination wrenches continued until the late 1990s or early 2000s.

In addition to Truecraft, brands known to have been produced by AIGO include Bernzomatic, Cen-Tech, Chicago Industrial, Chicago Pneumatic, Globemaster, KAL, and Tatools.

Factory Construction in Niigata?

The company's history notes the 1969 construction of a factory in Niigata to increase forging capacity, but we think this was probably an expansion of the existing Shinbo facility.

In 1973 the company received JIS certificate 373112 for class B4632 (box-end wrenches), but we don't have a JIS record for this. A later record for this certification can be seen in the 1982 JIS Summary for Class B4632.

On October 4, 1974 the company received JIS certificate 374091 in class B4604 (adjustable wrenches), with notes indicating fully-forged production, 23° jaw angle, and "H" (heavy) grade. The record for this certification can be seen in the 1974-10 Monthly Report for JIS 374091.

New President

In 1975 Akio Aida (相田明雄) became president after the death of the founder.

New Factory at Tsukanome

In 1977 the company opened a new factory in 2153-5 Tsukanome in Sanjo City, and moved the head office to the new factory location.

On February 22, 1978 the company received JIS certificate 373112 for class B4632 at the new factory. The record for this certification can be seen in the 1982 JIS Summary for Class B4632.

On February 22, 1978 the company received JIS certificate 374091 for class B4604 at the new factory. The record for this certification can be seen in the 1982 JIS Summary for Classes B4604 and B4606.

On February 13, 1979 the company received JIS certificate 366008 for class B4630 at the new factory. The record for this certification can be seen in the 1982 JIS Summary for Class B4630.

In 1983 the company installed NC milling machines and other equipment to automate the die-cutting process.

In 1991 the company installed CAD/CAM tools to improve its design capabilities.

Discontinued Operations

The company closed in 2011, and its last address was 2153-5 Tsukanome, Sanjo City, Niigata prefecture.

Our information on the company history was adapted from the CWC Japanese website and from an archived web page of the company's profile. The CWC website has an extensive article on AIGO's contract production on their AIGO OEM Edition [External Link] web page.

JIS Certification History

AIGO is known to have received JIS certifications for several classes, including B4604 (adjustable wrenches), B4630 (open-end wrenches), B4632 (box-end wrenches), and B4651 (combination wrenches).

Factory locations were in Shinbo (新保) and Tsukanome (塚野目), both in Niigata prefecture.

View Company History with Factories for AIGO Kōgyō.

View JIS Certification Events for AIGO Kōgyō.

Trademarks

AIGO registered several Japanese trademarks, as noted in the table below.

The early trademark #35-188 was for an interesting logo used by the company, which consisted of five "5" numerals arranged inside a circle. Five in Japanese is "Go", so this logo could be read as "Go-Go", perhaps a play on the founder's name.

Tool Identification

Tools made by AIGO were typically marked with the AIGO-Oval trademark #40-585.

Contract production by AIGO can sometimes be identified by forged-in codes on the shank. AIGO's codes consist of two lines, with an alphabetic character (typically B, D, or F) on the top line, and two numbers on the lower line.

5-5-Circle Logo

Fig. 3. 5-5-Circle Logo from Japanese Trademark #58-94000.

The scan in Fig. 3 shows the 5-5-Circle logo as it was presented for the Japanese trademark #58-94000.

Wrenches

AIGO 15mm Combination Wrench

Fig. 4. AIGO 15mm Combination Wrench, with Insets for Back Side, Edge View and marking Detail.

Fig. 4 shows an AIGO 15mm combination wrench with parallelogram panels, stamped with "AIGO" and the metric size on the front panel, with "Forged Alloy Steel" and "Japan" on the back panel.

The shank also has a forged-in code "B 15-3" visible to the left of the back panel, and shown as a close-up in the small inset.

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

The top inset shows an edge view of the wrench, illustrating the small bend in the shank to provide an offset for the box end.

Contract Production for Truecraft

AIGO did extensive contract production for the "Truecraft" brand managed by the Diado Corporation U.S.A., with production dates ranging from the mid 1960s to the early 2000s.

[AIGO] Truecraft 1108 8mm Combination Wrench

Fig. 5. [AIGO] Truecraft 1108 8mm Combination Wrench, with Insets for Back Side, Edge View, and Marking Detail, ca. 1975 to Early 1990s.

Fig. 5 shows an [AIGO] Truecraft 1108 8mm combination wrench with parallelogram panels, stamped with "Truecraft" and the metric size on the front panel, with "Drop Forged Steel" and "Japan" on the back panel.

The shank also has a forged-in code "B 8-85" visible to the left of the back panel, and shown as a close-up in the small inset.

The overall length is 4.2 inches, and the finish is chrome plating with polished faces.

This wrench can be identified as production by AIGO Kōgyō by the forged-in "B 8-85" code. Note that the shank has a small bend near the box end to provide the offset angle.

The numeric model number and plain Truecraft marking suggest production from around 1975 to the early 1990s.

[AIGO] Truecraft B423B 11mm Combination Wrench

Fig. 6. [AIGO] Truecraft B423B 11mm Combination Wrench, with Insets for Back Side, Edge View, and Marking Detail, ca. Late 1960s to 1975.

Fig. 6 shows a Truecraft B423B 11mm combination wrench with parallelogram panels, stamped with "Truecraft" and the metric size on the front panel, with "Drop Forged Tool Steel" and "Japan" on the back panel.

The shank also has a forged-in code "B 11-38" visible to the left of the back panel, and shown as a close-up in the small inset.

The overall length is 5.1 inches, and the finish is chrome plating with polished faces.

This wrench can be identified as production by AIGO Kōgyō by the forged-in "B 11-38" code. Note that the shank has a small bend near the box end to provide the offset angle.

The Truecraft alphabetic-prefix model number suggests production from the late 1960s to around 1975.

[AIGO] Truecraft [B434B] 22mm Combination Wrench

Fig. 7. [AIGO] Truecraft [B434B] 22mm Combination Wrench, with Insets for Back Side, Edge View and Marking Detail, ca. Mid to Late 1960s.

Fig. 7 shows a Truecraft [B434B] 22mm combination wrench with parallelogram panels, stamped with "Truecraft" and the metric size on the front panel, with "Drop Forged Tool Steel" and "Japan" on the back panel.

The shank also has a forged-in code "B 22-6" visible to the left of the back panel, and shown as a close-up in the small inset.

The overall length is 11.2 inches, and the finish is chrome plating with polished faces.

This wrench can be identified as production by AIGO Kōgyō by the forged-in "B 22-6" code. One construction detail to note is that the shank has a small bend near the box end.

Note that this wrench is not marked with a model number, but would have been model B434B in Truecraft's alphabetic-prefix model number system. The absence of a model number here is probably accidental, possibly due to a misunderstanding of what markings were required during the early production phase.

[AIGO] Truecraft B717 17mm Flex-Box Combination Wrench

Fig. 8. [AIGO] Truecraft B717 17mm Flex-Box Combination Wrench, with Insets for Back Side, Edge View and Marking Detail, ca. 1968 to 1975.

Fig. 8 shows a Truecraft B717 17mm flex-box combination wrench with raised oval panels, stamped with "Truecraft" and the metric size on the front panel, with "Chrome Vanadium Drop Forged" and "Japan" on the back panel.

The shank also has a forged-in code "B 17-1" visible to the left of the back panel, and shown as a close-up in the small inset.

The overall length is 10.2 inches fully extended, and the finish is chrome plating with polished faces.

This wrench can be identified as production by AIGO Kōgyō by the forged-in "B 17-1" code.

The alphabetic-prefix model number indicates production up to around 1975.

[AIGO] Truecraft B719B 19mm Flex-Box Combination Wrench

Fig. 9. [AIGO] Truecraft B719B 19mm Flex-Box Combination Wrench, with Insets for Edge View and Back Side Detail, ca. 1968 to 1975.

Fig. 9 shows a Truecraft B719B 19mm flex-box combination wrench with parallelogram panels, stamped with "Truecraft" and the metric size on the front panel, with "Drop Forged Tool Steel" and "Japan" on the back panel.

The shank also has a forged-in code "B 19-2" visible to the left of the back panel, and shown as a close-up in the small inset.

The overall length is 10.3 inches fully extended, and the finish is chrome plating with polished faces.

This wrench can be identified as production by AIGO by the forged-in "B 19-2" code, with the "B" indicating the raised parallelogram panels.

The Truecraft alphabetic-prefix model number indicates production up to around 1975.

[AIGO] Truecraft 1312 3/8 Flex-Box Combination Wrench

Fig. 10. [AIGO] Truecraft 1312 3/8 Flex-Box Combination Wrench, with Insets for Back Side, Edge View, and Marking Detail, ca. 1975 to Early 1990s.

Fig. 10 shows a Truecraft 1312 3/8 flex-box combination wrench with raised oval panels, stamped with "Truecraft" and the fractional size on the front panel, with "Drop Forged" and "Japan" on the back panel.

The shank also has a forged-in code "F 1-9" visible to the left of the back panel, and shown as a close-up in the small inset.

The overall length is 7.4 inches fully extended, and the finish is chrome plating with polished faces.

This wrench can be identified as production by AIGO Kōgyō by the forged-in "F 1-9" code.

The numeric model number and plain "Truecraft" marking suggest production from around 1975 to the early 1990s.

[AIGO] Truecraft 1318 9/16 Flex-Box Combination Wrench

Fig. 11. [AIGO] Truecraft 1318 9/16 Flex-Box Combination Wrench, with Insets for Back Side, Edge View, and Marking Detail, ca. 1994 to Early 2000s.

Fig. 11 shows a later Truecraft 1318 9/16 flex-box combination wrench with raised oval panels, stamped with the "Truecraft" Hex logo and the fractional size on the front panel, with "Drop Forged Truecraft" and "Japan" on the back panel.

The shank also has a forged-in code "F 4-46" visible to the left of the back panel, and shown as a close-up in the small inset.

The overall length is 10.3 inches fully extended, and the finish is chrome plating with polished faces.

This wrench can be identified as production by AIGO Kōgyō by the forged-in "F 4-46" code.

The "Truecraft" Hex logo marking suggests production in 1994 or later.

Contract Production for Other Brands

AIGO provided contract production for a number of U.S. and international brands.

[AIGO] Chicago Industrial 9/16 Combination Wrench

Fig. 12. [AIGO] Chicago Industrial 9/16 Combination Wrench, with Insets for Back Side and Edge View.

Fig. 12 shows a Chicago Industrial 9/16 combination wrench with raised oval panels, stamped with "Chicago Industrial" and the fractional size on the front panel, with "Forged Alloy Steel" and "Japan" on the back panel.

The shank also has a forged-in code "F 4-72" visible at the left of the back panel.

The overall length is 6.6 inches, and the finish is chrome plating with polished faces.

The top inset shows a profile view of the wrench, illustrating the bend in the shank to provide an offset for the box end.

This wrench can be identified as AIGO production by the forged-in code "F 4-72", with the "F" code indicating a raised oval panel.

An'naka Kōgu

The company was founded by Kojiro Annaka (安中幸二郎) in Hiraoka, Osaka as a maker of adjustable wrenches.

JIS Certification

On May 13, 1952 the company received JIS certificate 1448 for adjustable wrenches (class B4604). The record for this certification can be seen in the Monthly Report 1952-09 for Class B4604.

Contract Production

The company is known to have provided adjustable wrenches to Nissan and other companies. These wrenches were typically marked "Partial Forged" with a JIS "P" suffix.

JIS Release and Company Closure

On March 5, 1984 the company released its JIS 1448 registration and is assumed to have closed shortly afterwards. The record for the JIS release can be seen in the Monthly Report 1984-03 for JIS 1448 Release.

JIS Certification History

View Company History with Factories for An'naka Kōgu.

View JIS Certification Events for An'naka Kōgu.

ARM Sangyō

The company was founded in 1946 in Yokocho, Sanjo City as a maker of hardware products.

New Factory in Higashi-Uradate

In 1960 the factory moved to Higashi-Uradate in Sanjo City, and in 1961 began making forged tools.

New Factory in Shimoda

In 1973 the company was reorganized as Kawahiro Tankōsho (川広鍛工所), and the factory relocated to Shimoda-mura in the Minamikanbara District of Niigata Prefecture (新潟県南蒲原郡下田村).

Name Change to ARM Sangyō

In 1978 the company changed its name to ARM Sangyō (アーム産業).

In 1979 the company began producing pliers and bolt clippers.

JIS Certification

On May 27, 1980 the company received JIS certificate 380043 for pliers in classes B4623, B4631, and B4631. The record for this certification can be seen in the 1999 Summary for Super-Class B010.

On April 14, 1987 the company received JIS certificate 387005 for bolt clippers in class B4643. The record for this certification can be seen in the 1999 Summary for Super-Class B090.

Pipe Wrenches

In 1991 the company began making pipe wrenches, and on November 18, 1992 the company received JIS certificate 392057 for pipe wrenches in class B4606. The record for this certification can be seen in the 1999 Summary for Super-Class B013.

JQA JIS Certification

On December 14, 2007 the company received JQA certificate JQ0307055 for class B4606.

Continuing Operations

The company continues in business and more information can be found at the ARM Sangyō [External Link] website. We adapted our history from the timeline on the company's website.

JIS Certification History

The factory location is in Shimoda.

View Company History with Factories for ARM Sangyō.

View JIS Certification Events for ARM Sangyō.

Asahi Kinzoku Kōgyō (Asahi Metal Industries)

Asahi Kinzoku Kōgyō (旭金属工業) produces wrenches and other tools under the "Asahi Tools" brand and currently operates in Tsubame, Niigata Prefecture, Japan.

The company began in 1931 as the Miyano Company, a seller of iron pipe fittings operating in Minamidori, Shinmachi, Osaka.

Formation of Asahi Kōgu Seisakusho

In 1935 the company was reorganized as the Asahi Kōgu Seisakusho and began manufacturing wrenches.

In 1949 the company established Asahi Kinzoku as a spanner specialty distributor, which in 1951 was reorganized to establish the Asahi Kinzoku Company, Ltd.

Asahi Kinzoku Kōgyō with Factory at Fuse

In 1954 the manufacturing division was separated as the Asahi Kinzoku Kōgyō Company, Ltd. in Fuse City, Osaka Prefecture.

JIS Certification

On August 15, 1958 the company received JIS certificate 6159 for class B4630 (open-end wrenches). The record for this certification can be seen in the Monthly Report 1958-08 for JIS 6159. (This certification is not mentioned in the company's history.)

New Main Factory at Yao

In March of 1960 the company relocated its main factory to Yao City in Osaka Prefecture.

On June 6, 1961 the company received JIS certificate 8117 for class B4630 at the Yao factory. The record for this certification can be seen in the section on the 1962 JIS Summary for Class B4630.

Shin Nihon Tool Subsidiary

In 1970 the company established the Shin Nihon Tool Company, Ltd. as a sales subsidiary, and Shin Nihon Tool registered "S.N.T" as a trademark.

JIS Certification for Socket Tools

In 1976 the company received JIS certificate 576049 in classes B4638 (spinner handles) and B4641 (ratchet handles) at the Yao factory. The record for this certification can be seen in the section on the 1982 Certified List for Classes B4638, B4640, and B4641.

Acquisition of Sanjō Asahi and Shin Nihon Tankō

Based on research done by the CWC site, in 1981 Shin Nihon Tool formed Shin Nihon Tankō by acquiring a factory from the Kita Nihon Tanzo Company, a maker of wrenches operating at Higashi-Irifune in Niigata City. This set the stage for a merger that brought Asahi to Niigata Prefecture.

In 1982 Asahi Kinzoku Kōgyō acquired Sanjō Asahi and Shin Nihon Tankō, both in Niigata Prefecture. Asahi continued to operate the factory at Higashi-Irifune acquired with Shin Nihon Tankō, and on April 1, 1982 JIS 372165 was transferred from Shin Nihon Tankō to Asahi.

New Factory at Yoshida

After beginning operations in Niigata at Higashi-Irifune, Asahi built a new factory at Yoshida-cho, Nishikanbara-gun, Niigata Prefecture. Soon afterwards the company moved its head office factory to Yoshida-cho.

Over the next few years the company received JIS certifications for classes B4630, B4632, and B4636-B4641 at Yoshida-cho.

A civic reorganization in Niigata later made Yoshida-cho part of the city of Tsubame, and in 2007 the company absorbed its Shin Nihon Tool sales subsidiary and consolidated manufacturing and sales with the head office in Tsubame.

Continuing Operations

Asahi Kinzoku Kōgyō currently offers the Revowave line of tools with ergonomic design, and a LIGHTOOLS line of wrenches with cutout handles to minimize weight.

The company maintains a website (in Japanese, English, and Chinese) at Asahi Tools [External Link]. Our history was adapted from the historical timeline on the Japanese website and from the CWC website.

JIS Certification History

The company received a number of JIS certifications for class B4630, as manufacturing took place in multiple factories and each location needed to be certified. Later certifications covered classes B4632 and B4651, as well as socket tools in classes B4636-B4641.

Factory locations were in Fuse and Yao in Osaka prefecture, and later in Yoshida-cho (now Tsubame) in Niigata prefecture.

View Company History with Factories for Asahi Kinzoku Kōgyō.

View JIS Certification Events for Asahi Kinzoku Kōgyō.

Trademarks

Tool Identification

Tools from Asahi Kinzoku Kōgyō are typically marked "Asahi Tools" with the ASH-Hex logo, or with one of the other trademarks noted in the table above.

Note though that "Asahi" is a very popular brand in Japan for everything from beer to newspapers, and there are known to be other "Asahi Tools" markings unrelated to Asahi Kinzoku Kōgyō. Thus the ASH-Hex logo (or another trademark) will be a more reliable indicator of the company's production.

ASH-Hex Logo

Fig. 13. ASH-Hex Logo from Japanese Trademark.

The scan in Fig. 13 shows the ASH-Hex logo as it was presented for the Japanese trademark #44-31483.

The trademark logo intentionally omits the period following the "H", although this final period was sometimes marked on tools.

Fig. 14. ASH-Hex Logo.

Fig. 14 shows the ASH-Hex logo as found forged into the shank of an Asahi Tools 36x41mm Offset Box-End Wrench.

Asahi Tools

Asahi Tools 36x41mm Offset Box-End Wrench

Fig. 15. Asahi Tools 36x41mm Offset Box-End Wrench, with Inset for Edge View and Back Side Detail.

Fig. 15 shows an Asahi Tools 36x41mm offset box-end wrench, marked with "Asahi Tools" and the ASH-Hex logo forged into the front, with "Chrome-Vanadium" and a "40-77" code forged into the back side.

The metric sizes are stamped with "41" on the front and "36" on the back.

The overall length is 18.4 inches, and the finish is chrome plating.

The absence of a "Japan" marking on this tool indicates that it was originally produced for the Japanese domestic market.

Daiichi Kōgyōsho

Daiichi Kōgyōsho (第一工業所) was a maker of adjustable wrenches operating in Edogawa, Tokyo.

The company was founded in 1939 as a maker of railway equipment and began producing wrenches after the war, with a factory at 2-658 Nishikohirogawa, Edogawa-ku, Tokyo.

"Victor" and "Lion" Brands

The company's adjustable wrenches were sold under the "Victor" and "Lion" brands, both of which were trademarks of Yuasa Hardware, a major distributor of metal products.

JIS Certification

On June 28, 1951 the company received JIS certificate 654 for adjustable wrenches in class B4604 and was one of the first five companies to be certified in this class. The record for this certification can be seen in the section on the Monthly Report 1952-01 for Classes B4604 and B4605.

Discontinued Operations

Daiichi Kōgyōsho released its JIS certification in 1984 and the company is presumed to have closed at that time.

Our history of the company is based on information from the CWC website.

JIS Certification History

View Company History with Factories for Daiichi Kōgyōsho.

View JIS Certification Events for Daiichi Kōgyōsho.

Daiei Tankōsho

Daiei Tankōsho (大栄鍛工所) was founded in 1962 in Sanjo City, Niigata Prefecture and initially operated as a maker of forged power tools.

"DAIE" Brand Tools

The company is known to have made hand tools, in particular combination wrenches and box-end wrenches. Tools were marked with the "DAIE" brand.

JIS Certification

The company is believed to have JIS certification for class B4632 (box-end wrenches) based on a known tool, but we haven't found a record for the certification.

Continuing Operations

The company continues in business today at 739-1 Kamihonai, Sanjo City (新潟県三条市上保内739-1), with Jun Hashimoto (橋本 潤) as president and company representative. Additional information can be found at the daiei-forging.co.jp [External Link] website.

The website doesn't provide a history timeline, but it does have some photos of their impressive forging equipment.

Daie 13x17mm Offset Box-End Wrench

Fig. 16. Daie 13x17mm Offset Box-End Wrench, with Insets for Back Side, Side View and Marking Detail.

Fig. 16 shows a Daie 13x17mm offset box-end wrench with recessed panels, marked with "DAIE" and "JIS-B4632" forged into the front panel, with "Chrome-Vanadium" and "Japan" code forged into the back panel.

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

The "JIS-B4632" marking refers to the JIS standard for box-end wrenches, presumably indicating that the company has a JIS certification for box wrenches.

Dia Seikō

Dia Seikō (ダイヤ精工) was a maker of wrenches and other tools operating in Sanjō City, Niigata prefecture. Dia Seikō was the successor in 1984 to Inoue Seisakusho, a maker of tools with roots going back to 1930.

The Inoue company was founded in 1930 as a maker of household hardware in Sanjo City, with a factory at 2523 Tajima (三条市大字田島2523).

By 1937 the company was making locks and changed its name to the Inoue Jōmae Kōjō (井上錠前工場).

During the war the company began making tools as a subcontractor to the Kurashiki Aircraft Company.

In 1950 the company was reorganized as Inoue Seisakusho (井上製作所).

Between 1956 and 1960 the company supplied wrenches as contract production for several motorcycle brands.

During the 1960s the company sold wrenches under the "IS" brand and began exporting to Europe. In 1964 the company registered a Japanese trademark with "I.S." in a diamond outline with a sailing yacht.

By 1972 the company had begun production of adjustable wrenches.

JIS Certification

On April 19, 1976 the company received JIS certificate 376004 for adjustable wrenches (class B4604) at the Sakae factory, with notes indicating fully forged production in "Strong" grade. The record for this certification can be seen in the 1982 Certified List for Class B4604.

On October 2, 1979 the company received JIS certificate 379123 for wrenches in class B4630, with the factory address listed as 1620 Fukushima Shinden, Sakae Village, Nishikanbara County in Niigata Prefecture. The record for this certification can be seen in the 1982 Certified List for Class B4630.

Reorganization into Dia Seikō

By 1984 the company was having financial problems and was reorganized into Dia Seikō. Although there are reports that Inoue Seisakusho had gone bankrupt, the reorganized company seems to have regarded it as simply a name change with maybe some new investment. The new company continued operating at the same location, and appears to have continued producing the same products.

"Tough" Trademark

In 1985 Dia Seiko was granted a trademark for "Tough", a brand that had been used by Inoue Seisakusho since around 1982. The trademark application had been filed by the earlier company.

JIS Transfer

On March 17, 1992 Dia Seikō transferred the 1979 JIS registration 379123 from Inoue Seisakusho into its own name. The record for this transfer can be seen in the Monthly Report 1992-03 for JIS 379123 Transfer.

One of the interesting details of this transfer is that the new registration kept the old number and date, instead of using the date of the transfer itself, or possibly being assigned a new JIS number.

In addition, the transfer extended the JIS coverage to classes B4632 and B4651. A later record of the transfer can be seen in the 1999 Summary for Super-Class B027, which shows JIS 379123 with the 1979 date and applying to classes B4630, B4632, and B4651.

This provides evidence that the 1984 reorganization of Inoue Seisakusho was considered as something less serious than a bankruptcy, or at least that the JIS inspector accepted the company's story that it was just a change of name with maybe a new investor. Normally with a bankruptcy the JIS registrations would be canceled, on the grounds that a financial breakdown would impair the company's quality standards.

Discontinuation of Tool Production

In 2005 Dia Seikō discontinued its tool production, but remained in business for other product lines.

The company website is still available at diaseiko.com [External Link], but has not been updated for a number of years.

JIS Certification History

Inoue Seisakusho and Dia Seikō received JIS certifications for classes B4630, B4632, and B4651.

View Company History with Factories for Dia Seikō.

View JIS Certification Events for Dia Seikō.

Fujiya

Fujiya (フジ矢) is a maker of pliers founded in 1923 in Osaka City.

The company was founded in 1923 as the Michimoto Iron Works (道本鉄工所) by Saichiro Michimoto (道本佐一郎), with operations in Ikuno ward of Osaka City (大阪市生野区).

In 1944 the company was reorganized as the Osaka Pliers Company (大阪ペンチ株式会社).

Earliest JIS Certification

On June 28, 1951 the company received JIS certificate 651 for class B4623 (side-cutting pliers) at the Ikuno factory, making it one of the first tool companies to receive JIS certification. The record for this certification can be seen in the section on the 1955 JIS Summary for Classes B4623-B4625. [Editor's note: unfortunately the Fujiya website history incorrectly reports the 1951 JIS certification as class B4631 (needlenose pliers).]

New Factory at Matsubara

In October of 1968 the company relocated its head office factory to 363 Matsubara in Higashi-Osaka City (大阪府東大阪市松原363番).

On October 24, 1969 the company was re-certified for JIS 651 in class B4623 at the Matsubara factory, with notes indicating normal and heavy grade. The record for this certification can be seen in the section on the 1972 JIS Summary for Classes B4623-B4625.

Name Change to Fujiya Pliers Company

In 1973 the company changed its name to the Fujiya Pliers Company (フジ矢ペンチ株式会社).

New Factory at Kano

In 1976 the company opened at new factory at Kano, Higashiosaka City (東大阪市加納). The Kano factory operated as a second production facility, and Matsubara remained the head office factory until 2016. [Editor's note: did the Kano factory receive any JIS certifications?]

Name Change to Fujiya Company

In 1993 the company changed its name to the Fujiya Company (フジ矢株式会社) and moved the head office factory to 2-6-32 Matsubara (東大阪市松原２丁目６番３２号).

New Company President

In 1998 Yasunobu Nozaki (野﨑恭伸), the grandson of the founder, became company president.

New JQA JIS Certification

On July 17, 2008 the head office factory at 2-6-32 Matsubara received JQA certification JQ0508059 for pliers in classes B4623, B4625, B4631, and B4635.

Acquisition of Hanazono Tools

In 2015 the company acquired Hanazono Tools, which continued to operate as a subsidiary of Fujiya.

New Head Office Factory

In November of 2016 the company opened a new head office factory, and also established the Victor Company. [Editor's note: what is the address of the new factory? Did the Kano factory continue in operation?]

Acquisition of Wakahori Manufacturing Company

In 2017 the company acquired Wakahori Manufacturing, which continued to operate as a subsidiary of Fujiya.

Continuing Operations

The company continues in operation today with its head office at 2-6-32 Matsubara, Higashiosaka City, Osaka Prefecture. The company also has subsidiaries in Japan and in Vietnam.

More information can be found at the Fujiya [External Link] website, which has has an informative History Timeline [External Link]. We adapted our history from the company's history timeline.

JIS Certification History

Fujiya is known to have received JIS certifications for classes B4623, B4625, B4631, and B4635.

View Company History with Factories for Fujiya.

View JIS Certification Events for Fujiya.

Hattori Supana (TORI)

The company was founded in 1918 as the Hattori Hiroshi Iron Works, presumably by the eponymous Hiroshi Hattori (服部廣鐵). The company operated in Atsuta Ward of Nagoya City in Aichi prefecture.

By 1941 the company was advertising wrenches, which were typically marked with "TORI" as a brand, although it wasn't registered as a trademark.

Name Change to Hattori Supana

By 1952 the company name had changed to Hattori Supana (服部スパナ).

Early JIS Certification

Hattori was one of the first seven companies to receive JIS certification for class B4630 (open-end wrenches), for which it received JIS certificate 1979 in November of 1952. The certification record can be seen in the section on the Monthly Report 1952-11 for Class B4630.

Discontinued Operations

The company is believed to have ceased operations by around 1970.

JIS Certification History

Hattori Supana is known to have received JIS certification 1979 for class B4630 (open-end wrenches).

The 1952 JIS certification listed the factory address as 28 Umedacho, Atsuta Ward, Nagoya City.

View Company History with Factories for Hattori Supana.

View JIS Certification Events for Hattori Supana.

Hokuyo Sangyō

Hokuyo Sangyō was a maker of wrenches, pliers and other tools operating in Niigata prefecture. The company was originally a division of Sanjō Kikai Seisakusho, a maker of machinery and tools, and remained closely associated with the parent company after a 1948 spinoff.

Formation of Hokuyo Sangyō

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 1950.

JIS Certification for Sanjō Kikai

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.

On June 17, 1954 Sanjō Kikai received certification 3195 for B4614 (combination pliers), with the address listed as 1310 Yokkaichi in Sanjo City. The record for this certification can be seen in the 1955 JIS Summary for Class B4614.

Transfer of Production

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.

JIS Certification for Hokuyo Sangyō

On January 13, 1964 Hokuyo Sangyō received JIS certification 9786 for class B4604 (adjustable wrenches), with notes indicating a 15° offset in normal and heavy grade, and with the factory address at 4144 Nishi Honjoji in Sanjo City. The record for this certification can be seen in the 1967 JIS Summary for Classes B4604 and B4606.

On the same date the company alse received JIS 9787 for class B4614 (combination pliers), and the record for this certification can be seen in the 1967 JIS Summary for Class B4614.

Later on September 15, 1964 the company received 364147 for class B4630 (open-end wrenches), but this record listed a different factory address at 1825 Higashi Honjoji in Sanjo City. The record for this certification can be seen in the 1967 JIS Summary for Class B4630.

New Factories at Higashi Honjoji and Nishi Honjoji

The fact that Hokuyo Sangyō received JIS certification in 1964 shows that it was managing its own factories by this time, and the different addresses indicate that Hokuyo Sangyō had two production facilities.

On August 1, 1968 Hokuyo Sangyō received JIS certification 9786 for class B4604 (adjustable wrenches), and JIS certification 9787 for class B4614 (combination pliers). The records for these certifications can be seen in the 1972 JIS Summary for Classes B4604 and B4606 and 1972 JIS Summary for Class B4614. Both certifications listed the factory address as 1825 Higashi Honjoji in Sanjo City.

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 1972 JIS Summary for Class B4632. (The certification for JIS 369042 was later transferred to JIS 364147.)

New Factory at Sakae

The 1999 JIS Summary later gave the address for the factory as Tsuchiba 7-54 in Sanjo City (新潟県三条市土場７番５４号). The company referred to this as their Sakae (本社栄) factory in the JIS certification for box-end wrenches.

Based on the change of address, it appears that the company had established a new factory sometime after 1982.

Contract Production

Hokuyo Sangyō was active as a contract manufacturer for other companies, most notably for KTC. Examples are known of KTC adjustable wrenches marked with JIS 9786, indicating production by Hokuyo Sangyō.

The company also produced adjustable wrenches for the Fuller Tool Company and Award Tool Company, which were typically marked with a small "SANKI" forged into the tool.

Water Pump Pliers

On December 27, 1985 Hokuyo Sangyō received JIS certification 385133 for class B4626 (water pump pliers) at the Sakae factory. The record for this certification can be seen in the 1999 JIS Summary for Super-Class B070.

The "SUNKEY" Brand

In 1984 a similar brand "SUNKEY" was registered as a trademark, again by Sanjo Machinery.

By the early 1990s the SUNKEY brand had superseded the SANKI brand.

Discontinued Operations

By 2002 the Hokuyo Sangyō website was no longer available and the company is assumed to have closed.

JIS Certification History

View Company History with Factories for Sanjō Kikai.

View JIS Certification Events for Sanjō Kikai.

Hokuyo Sangyo 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).

View Company History with Factories for Hokuyo Sangyō.

View JIS Certification Events for Hokuyo Sangyō.

Adjustable Wrenches

Sanki 250mm (10 Inch) Adjustable Wrench

Fig. 17. Sanki 250mm Adjustable Wrench, with Insets for Back Side, Side View, and Construction Detail.

Fig. 17 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 moveable 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.

Contract Production for Fuller Tool

Hokuyo Sangyō was a major supplier to the Fuller Tool Company, an American tool company with a major Japanese import business.

[Sanki] Fuller No. 6 6 Inch Adjustable Wrench

Fig. 18. Fuller No. 6 "SANKI" 6 Inch Adjustable Wrench, with Insets for Back Side, Side View, Construction Detail, and Marking Detail, ca. 1970s.

Fig. 18 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 moveable 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.

[Sanki] Fuller No. 10 10 Inch Adjustable Wrench

Fig. 19. Fuller No. 10 "SANKI" 10 Inch Adjustable Wrench, with Insets for Back Side, Side View, Construction Detail, and Marking Detail.

Fig. 19 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 moveable 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.

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 suggests Sanki may have been copying a feature on KTC wrenches. 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.

Contract Production for Sears Roebuck

Hokuyo Sangyō was a major production partner for KTC and is known to have supplied the majority of KTC-branded adjustable wrenches in the 1960s to 1970s time frame. In addition, Hokuyo Sangyō was also a major supplier of adjustable wrenches to Fuller.

Thus when KTC began supplying tools to Sears Roebuck for the "BF" series, it's not surprising that Hokuyo Sangyō also became a supplier to Sears.

[Sanki] Sears 30874 "BF" 6 Inch Adjustable Wrench

Fig. 20. Sears 30874 "BF" 6 Inch Adjustable Wrench, with Insets for Back Side, Side View, Construction Detail and marking Detail, ca. 1972+.

Fig. 20 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 moveable jaw.

Note also that the tailpiece narrows rapidly to the cylindrical section of the moveable 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 Sears 6 inch adjustable wrenches had catalog number 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.