A spud wrench, also known as a pipe wrench or Stillson wrench, was a specialized adjustable wrench used primarily in plumbing and pipefitting to grip and turn threaded pipes and fittings. The unique jaw design of the spud wrench allowed it to firmly grip pipes and rods without crushing them and enabled the tool to be used on a variety of pipe sizes and shapes.
Page Contents
History of the Spud Wrench
The original spud wrench was invented in 1869 by Daniel C. Stillson, who worked as a steamboat fireman in Somerville, Massachusetts. At the time, the common monkey wrench was used to tighten pipes and fittings, but it often slipped and damaged pipe threads. Stillson devised a wrench with adjustable parallel jaws that could firmly grip pipes without crushing them.
Stillson patented his wrench design on April 20, 1869 and assigned the patent to William Walker of Worcester, Massachusetts. Walker began mass producing the “StillsonImproved Pipe Wrench” in 1870. The tool was an immediate success with plumbers, steamfitters, and gasfitters due to its sturdy grip. By the 1880s, over 120,000 Stillson wrenches were being produced annually in the United States.
In 1886, brothers Frank and William Petersen of Chicago designed a similar wrench known as the Trimo Pipe Wrench. Their design improved on Stillson’s by adding teeth to the jaws to improve grip. The Petersen brothers’ wrench became the main competitor to the Stillson wrench. Due to its popularity, the term “spud wrench” emerged as a generic nickname for either Stillson’s or Petersen’s adjustable jaw pipe wrenches.
Design and Use of the Spud Wrench
The key to the spud wrench’s functionality is its adjustable parallel jaws. The jaws are connected by a threaded worm gear that allows the operator to quickly adjust and retain the jaws’ grip on a pipe or fitting. The jaws have serrated or grooved teeth to firmly grip the pipe without damaging the threads.
To use a spud wrench:
- Loosen the adjustable nut to open the jaws
- Place the jaws over the pipe or fitting
- Tighten the adjustable nut which closes the jaws
- Turn the handle to tighten or loosen the pipe
Spud wrenches came in a range of sizes from 6 inches to 60 inches long to accommodate different pipe diameters. The length of the handle gave the user increased leverage when twisting stubborn pipes. The head and handle were typically forged from high carbon steel for strength and durability.
Advantages of the Spud Wrench
Spud wrenches offered several advantages over other pipe wrenches:
- Could grip round, hexagonal, or octagonal pipes
- Jaws retained grip without crushing or damaging pipe
- Durable steel construction resisted bending and breaking
- Adjustable jaws accommodated range of pipe sizes
- Long handle provided high twisting force
- Teeth or serrations prevented slippage
These benefits made the spud wrench the go-to tool for steamfitters, plumbers, and gasfitters from the late 1800s through the mid-1900s. It remains a popular hand tool for working with threaded pipe. Modern spud wrenches maintain a similar adjustable parallel jaw design to Stillson’s original patent.
Decline and Modern Use
The spud wrench began to decline in popularity in the 1950s and 60s as other pipe wrench designs emerged. The development of monkey wrenches with serrated jaws reduced slippage problems. Chain and strap wrenches also offered convenient alternatives for gripping pipe without damaging threads.
Increased use of welded and soldered pipes, and fittings such as compression sleeves that didn’t require threading, also decreased the need for spud wrenches. The specialized nature of the tool limited its versatility for mechanics compared to adjustable wrenches.
Today, spud wrenches are still produced and used by some plumbers and pipefitters who work with threaded pipe systems. They provide a sturdy grip on round threaded pipes that cannot be crushed. However, the majority of modern plumbers use pipe wrenches, adjustable wrenches, or pliers when assembling pipe.
Notable Models
Popular spud wrench models included:
- Stillson wrenches – The original Stillson Improved Pipe Wrench patented in 1869 with serrated angled jaws.
- Trimo wrenches – The Petersen brother’s 1886 patent with horizontal teeth on the jaws for gripping.
- Monkey wrenches – Single adjustable jaw wrenches that later gained serrated teeth.
- Reed Manufacturing Co. wrenches – Famous for the “Reed’s Patent” double diamond pattern on their Stillson-style wrench jaws.
These were all variations on the classic spud wrench design of adjustable parallel jaws. Specific brands were known for quality materials and sturdy gripping power.
Vintage Spud Wrenches Today
While no longer a go-to tool for modern plumbers, vintage spud wrenches from the late 1800s to early 1900s are popular collector’s items. Iconic models like Stillson Improved Pipe Wrenches and Reed Manufacturing Co. wrenches with patented jaw designs have antique value for collectors. Even worn vintage wrenches that have seen heavy use can fetch high prices due to their place in pipefitting history.
Vintage spud wrenches are also valued for their high-quality materials and construction compared to modern tools. Their forged steel heads and handles are durable and functional decades or centuries later. Collectors may search for specific name-brand or patent-marked spud wrenches that are in usable condition.
Restored vintage spud wrenches can still be used by antique tool enthusiasts, although precautions should be taken to avoid damage. Overall, these wrenches remain a nostalgic reminder of late 19th and early 20th century plumbing and steamfitting tools.
Conclusion
In summary, the spud wrench was a specialized adjustable pipe wrench used primarily from the late 1800s through the mid-1900s. Its unique parallel jaw design allowed it to firmly grip threaded pipes and rods without crushing them. Spud wrenches were invaluable to the work of plumbers, steamfitters, and gasfitters during the expansion of pipe infrastructure over the late 19th and early 20th centuries.
While other pipe wrench designs have largely replaced it today, the classic spud wrench remains appreciated by antique tool collectors and enthusiasts. Its legacy lives on as an iconic relic of early plumbing and steamfitting industries.