Tuesday, January 31, 2017

Vise Grips versus Mole Grips

It's been said that vise-grips are the wrong tool for every job. Most of us would beg to differ.

The story of William Petersen's invention of vise-grip locking pliers has been told thoroughly on many other websites. Suffice it to say, Petersen was a blacksmith who emigrated from Denmark to the U.S. in 1901 to seek his fortune.  He ended up in DeWitt, Nebraska and for twenty years he worked his smithy, while the trade declined as farmers turned from horses to tractors and automobiles.  For four years he worked on the invention that was to make him famous, receiving his first U.S. patent in 1921 with the locking lever patent being awarded 3 years later when he was 42 years old.  



I find the original tool somehow evocative of the Alien movie:




The Petersen Manufacturing Company, run by family members, wasn't formally founded in 1934, and it wasn't until 1938 that they opened their first official manufacturing plant in a defunct drug store in "downtown" Dewitt. 



Factory photos below from the Nebraska State Historical Society:






Sales were understandably slow during the Depression. It wasn't until 1935 that influential publications like Popular Mechanics and Popular Science took notice of the new tool:

Popular Mechanics, September 1935

Popular Science, December 1935

By 1941, the little plant was operating at capacity to fulfill government contracts. Defense industries used thousands of Vise-Grips. Thousands more were shipped to England for their aircraft industry.

Petersen’s patent expired in 1941 but a new patent was received in 1942 which incorporated a move from forgings to stampings among other changes introduced over the years since the original 1924 patent. 

The "handshake" trademark was applied for in 1949 and registered in 1951:






Petersen considered to refine the tool, adding curved jaws in 1948 and a C-clamp version several years later.  By 1952, the company could boast, rightly or wrongly, that their product was the "World's Most Famous Hand Tool!"




Above, an early No. 10W.  Note the shape of the cross-bar or "slider" in the example above.  It's purpose is to act like a piston on the lower, moveable jaw when the bottom lever is pulled upwards. Note also that both upper and lower jaws are forged, whereas the body of the tool is a steel stamping.  The female threads for the knurled adjuster on the end must have been an issue, as some previous owner has brazed a nut in place.  Once locked on a object, to release it you'd have to pull down on the lower lever to break it free, which might not be easy.

In 1950, Harold T. Jones received U.S. Patent 2,514,130 for a lock-release lever, which became the last major change to the tool's design.  Interestingly, it wasn't actually put on the market as the easy release lever until 1957. 


Above, a No. 10R.  Note the lock release lever, secured by a roll pin, later replaced by a rivet.  Also, the profile of the cross-arm has changed, with the bottom bump more rounded, making it easier for the release lever to bear against it as if on a cam.  Also, in what appears to me to be a retrograde move, the upper jaw is a stamping, with only the jaw serrations being forged and apparently brazed on, whilst the lower jaw remains forged in its entirety.    

In 1957, the modern design 10WR came on the market, boasting curved jaws and a wire cutter. 



1958
Over the next few years, new forms of the tool were produced:

1964
William Petersen died in 1962. That same year, Petersen Manufacturing opened a plant in Cumberland, Wisconsin for manufacturing twist drills.  By the late 1970's, the company was employing 640 people.  In 1979, another plant was opened in Gorham, Maine to manufacture Hanson and Irwin branded tools.  

Long-nose Vice-Grips were introduced in 1980. 

1984

1985

1985

1986

(In light of what follows, the copy on the ad above--"If you don't think the Vise-Grip trademark makes a difference, think again"-- is ironic in the extreme.)

In 1985, the Petersen Manufacturing was renamed American Tool Companies, Inc.  In 1993, they acquired the Irwin Tool Company. Then, in 2002, the company sold out to Newell Rubbermaid, which had been a minority owner since 1985.  Following this change in ownership, the DeWitt plant operated under the name of the Irwin Industrial Tool Company.  Full of optimism, the small town of DeWitt paid for additional infrastructure (roads, sewers) to better serve the tool plant.  Now here comes the predictable but sad part: six years later, on Hallowe'en night 2008, the original Vise-Grip manufacturing plant in Dewitt, Nebraska, was closed when the parent company moved production to China. Over 330 people from Dewitt (population 600) and surrounding communities were put out of work. (Corporate decision makers really are bastards!)  In August 2016, the former Petersen factory was bought by Malco Products Limited, a Minnesota manufacturer of specialty tools.  It remains to be seen what becomes of it.

With the expiry of the original Petersen patent in 1941, considerable competition was spawned. This included an interesting variant in my collection patented by Francis Snell in 1945 in the US and manufactured by the BMC Manufacturing Corp. of Binghamton, NY.  The wrench is difficult to use and probably wasn’t much of a threat to Petersen, so the “Botnick Motor Corporation” went on to other things and appears to have survived as a car dealership. 




Another one-off was the "Gripso" tool offered by the H.R. Basford Company of San Francisco, which seems only to have made, or just distributed, this tool.  (An H.R. Basford Company in San Francisco at the time was a distributor for Columbia Records--perhaps the same firm in the hurly-burly merchandising world of the 1940's and 50's.)


Popular Mechanics, December 1949

Popular Mechanics, January 1958

The Gripso tool was based on a 1950 patent by Lawrence C. Mead:


The Connecticut firm of Seymour Smith & Son Inc. also offered their "Snap-Lock" plier-wrench, which also used the 1950 Harold Jones patent for a release lever:




A visitor from Vancouver was kind enough to send photos of his Seymour-Smith Model 2607 (7-inch) plier-wrench:






Note the swiveling lower jaw.  The release mechanism is also quite unique, acting from the upper arm of the tool and pushing downward on the bottom lever as the release trigger is pulled upward.  It looks like it may have been based on Harold Jones' later (1952) patent:


Most of the other imitators were just variations on a theme.  Below, a version from Bonney.  Note that there's no easy release lever, although a useful feature, as in the Seymour-Smith version above, is the pivoted bottom jaw:






Below, an early Craftsman offering (image snagged from fleabay):





With a release lever in the middle of the cross-arm, they're certainly different.  Kind of ugly, though.  They had disappeared from the Sears catalogue at least as early as 1975.

Below, "Grillagrip" pliers (image from the web), also with a release lever as above:  



Although this example was made in Spain, it was originally made in Britain where it was stamped with "PROV PAT 1744/57." This was an application filed in 1957 by Edward Richard Varney of E.R. Varney Ltd. in Sheffield.


Below, another tool in my collection with no identification whatsoever.  That's unfortunate because it's actually quite robustly made and is something of a hybrid between a Petersen 10W and 10R:





The teeth on the bottom jaw seem to be held in place in part through an insert:




Channellock also offered their "GripLock", a rather complicated looking version based on a U.S. patent issued in 1970 to Frank Patrick of Meadville, with the specific goal of reducing the shock when releasing toggle pliers. (Channellock still uses the "GripLock" name today, but applies it only to tongue-and-groove pliers.)



May 1966


May 1966


For some reason, possibly production costs, by the later 1970's they seem to have changed to a simpler model, based on a later patent by the same Mr. Patrick:


Channelock changed the name to much more awkward TOG-L-LOCK.  Below, as offered in the 1977 Herbrand tool catalogue, alongside Petersen versions:





The Fuller Tool Company, originally out of Whitestone, New York but now of out Montreal, got into the game.  Below, a total Petersen knock-off, made in Taiwan:



Up here in Canada, Canadian Tire offered a version under their Mastercraft brand, made by who knows as pretty much a clone of the Petersen tool:


There were (and are) some truly terrible versions.  Below, two that ended up only for use on my welding table, and even then they're not really up to the job:



This brings us to the British offering, namely the Mole "Self-Grip" pliers.  These were so common in that country that to this day "mole grips" is used synonymously with locking pliers, just as "vice grips" is used in North America.  Below, two of my pairs:




M. Mole & Son, originally located at 51-54 Charlotte Street in Birmingham, was founded in 1835, making what I have been unable to determine.  In any event, they went public in 1937 and found themselves making pressings for Rolls-Royce Merlin engines in 1939. Enter Scottish-born Thomas Robb Coughtrie (1917-2008), an electrical engineer educated at Bellshill Academy. In 1940 he joined the staff of the Chief Inspector of Electrical and Mechanical Equipment, with responsibility for examining all equipment in these categories being built in Scotland and Northern Ireland. He then went onto be responsible for the installation, inspection and maintenace of the 1,000 ton 'Whale' floating roadways built for the Mulberry Harbours so essential to supplying the invasion force after D-Day. After the war, in 1947 he started working for the Birmingham engineering firm M. K. Mole and Son. Following the deaths in 1948 and 1950 of the two Mole brothers, he became managing director of the company. According to many online sources, in 1955 he patented the self-grip wrench which became available the same year in both 7- and 10-inch straight and curved jaw models.


1955

1960


In 1960 the Mole company, and Coughtrie, relocated to their new Crindau Works on Albany Street in Newport, Monmouthshire, Wales, located off of the Bristol Channel just east of Cardiff. Their factory was adjacent to the eastern entrance of the Brynglas Tunnels on the M4 and employed around 600 people.



The company's wrenches came to the attention of Americans in the 1970's, although I don't think they ever had any distributors in North America.  The Mole C-clamp accessory, which turned the tool into something of a portable vise, was an interesting idea:
November 1971

Coughtrie's self-grip pliers bear a strong resemblance to the American vice-grips patented by Petersen.  Still, the Times credited Coughtrie with "his invention of the remarkable “Mole” self-grip wrench" and the city of Newport reportedly even had a sign at one entrance "Welcome to Newport--home of the mole wrench." In 1968, Coughtrie received an honourary doctorate from Heriot-Watt University.  Coughtrie went on to become a director of Cwmbrân New Town, governor of four local technical colleges and, in 1978, deputy lieutenant for Gwent (formerly Monmouthshire) and High Sheriff of the county in 1981. Interestingly, the Mole company appears to have sponsored an award, perhaps during Coughtrie's tenure:


Source:  Newport Past

The Mole company was around as late as 1977 but disappeared at some point after that.  It seems to have been bought by Stanley U.K., which currently uses "Mole Grips" as a trademark.  The former Newport factory, still called the Crindau Works, is now the home of Molynex Holdings PLC, which makes security systems. Below, photos from Google Maps:




A comparison of the Coughtrie and Petersen tools is instructive. First, the top jaws of the Mole wrench are riveted onto the frame, whereas the Vise-Grips top jaws are one forged piece: 



Whereas the cross-arm on a pair of Vise-Grips (below left) has a distinct bump in the middle of it, the cross-arm on Mole Grips (below right) is straight:





The Vise-Grip release lever has a longer reach beyond the pivot, and is curved at the end to bear against the cross arm.  In contrast, the Mole release arm extends only about 2 cm beyond the pivot, but the release arm itself is curved upwards to bear against the cross arm:


In action, the Mole Grips pull the quick release lever down, against the bottom arm of the pliers.  To release the pliers, you have to pull up on the lever:


In contrast, when closed the Vise-Grips release lever is held up towards the upper arm of the tool.  To release the tool, you push down on the lever, which in turn pushes up on the bump on the cross-arm.


The reason for this difference is that, on the Mole pliers, the load is between the lever and the fulcrum.  The lever is bent, and the top of the curved portion bears up against the straight cross-arm. As you pull up, the load (cross-bar) is moved upward. If you remember your high school physics, this makes it a Class 2 Lever:






In contrast, the lever on the Vise-Grips, the fulcrum is between the load and the effort. As you push down on the lever, the cross-bar is pushed up. This makes it a Class 1 Lever:

Based on my measurements (input arm distance divided by output arm distance), the Mole Grip provides a mechanical advantage of 3.5 to the Vise-Grip's 2.6.  Still, wheelbarrows are examples of Class 2 levers; teeter-totters are examples of Class 1 and I've always found teeter-totters easier.  In fact,  in my opinion Mole grips would have been better named after a bulldog with tetanus: once they grip something, releasing them is incredibly difficult!

I've only found one other brand of locking pliers that uses the Class 2 Lever form of release, the now defunct German tool maker Hoppe:




Compared to most of the other Hoppe tools I've collected, the quality of their version of the locking pliers is unarguably pathetic. I have to conclude that it's a bad copy of the British tool.

Anyway, here's the thing.  It's undisputed that William Petersen patented his Vise-Grip pliers in Nebraska in 1921. With respect to the Mole Self-Grip pliers, given Coughtrie's important wartime work, there can be no doubt that 40 or so years later the Scotsman encountered Petersen Vise-Grips at some point, since the Americans supplied those tools in great numbers to the British. Consequently, I think it's likely that he simply copied them. And why not? After all, the American patent had expired in 1941. However, the Jones patent for the release lever was issued in 1950. For US patents issued before 1995, the patent term is either 17 years from the issue date, or 20 years from the filing date of the earliest US or international application.  So, the Mole company could not legally have copied the release lever. Coughtrie could only get around this by devising his own lever.  This is exactly what he did,  applying for and receiving both a British and US patent. His 1957 US patent is for a "toggle relase means for a pivoted jaw wrench." Interestingly, in his application he cites both Mead's 1950 patent and a 1952 Jones patent.



While, at least in my opinion, his solution was not nearly as effective as the Jones one, it apparently breathed new life into the Mole firm and kept it chugging along for another few decades. I have the greatest admiration for Scottish mechanical ingenuity. But, to set the record straight, I'm sorry to have to give my opinion that Thomas Coughtrie didn't invent the self-grip wrench.  Instead, he copied the Peterson tool and contributed just a different release lever than in the 1950 Jones patent.  He does, however, enjoy the undeniable distinction of having popularized the tool in Britain. As for the modern Stanley Mole wrench, I have to wonder if it still uses the more awkward Coughtrie release system.  It rather looks like it, from the recent screen shot below:




If so, British tool users don't know what they're missing.  Pity.

Last, for the true connoisseur, a promotional belt-buckle from Mac Tools from years ago, currently offered for sale on e-bay.  The vise-grips are removable.  Impress the ladies!



2 comments:

Anonymous said...

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I am truly impressed with your research and accuracy.
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E. Peterson
Director of Sales and Marketing
Malco

The Duke said...

I'm glad to hear you enjoyed the article. If you're interested in talking to me, email me at bishrip@gmail.com.