This oddly-placed provincial plaque is located next to a 19th century cemetery, but preserves the history not of the cemetery but of an important and pioneering manufacturing company that still operates in its original building about .10 mile southeast of the marker.
The first firm in the world to produce socket-head screws, the P.L. Robertson Manufacturing Company was formed in Hamilton in 1907 and relocated here the following year. It was established by an Ontario inventor Peter Lymburner Robertson and, using an ingenious process he had developed to punch square holes into cold metal, it manufactured the innovative new screw for industrial markets. In its first two decades the company steadily expanded operations. By 1930, when the last patent on the Robertson screw and the equipment used in its manufacture expired, the firm had already begun to diversify its products. Now operated as the Robertson Whitehouse Company, it has become one of the largest manufacturers of light fasteners, including the original Robertson screw, in North America.
From the Robertson Whitehouse company website: (
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"Peter Lymburner Robertson -
The Great Canadian Inventor.
Peter frequently told the story- now a legend – about the accident in downtown Montréal. He was demonstrating a spring-loaded screwdriver when the blade slipped from the screw-slot and badly cut his hand. The incident inspired him, so he decided to invent an improved and safer screw – The Robertson® Drive.
P.L Robertson always looked for a better way of doing things and enjoyed working on new innovations. Peter was awarded his first ‘original’ screw patent for the Robertson® drive when he was 30 years old and over the years P.L was successfully named an inventor, businessman and author.
He settled his business in Milton, Ontario in 1908. The main company is building located on Bronte Street, where it still remains today. Robertson vastly expanded the local job market in Milton. Within five years of breaking ground the company had established a strong industrial/manufacturing presence in Milton. At that time, starting pay was 25¢ an hour. By 1950, employment peaked at close to 600 employees.
The first few years in Milton were hard for P.L and his company. Money was tight and the battle from local competitors was fierce. By 1912, he obtained two priceless advantages. The first, the Robertson® Drive had gained many customers because it made their operations faster and more profitable, secondly the patents he obtained on his screw and screw-making machinery had been granted internationally. This offered the possibility of worldwide markets.
To capture the global market PL Robertson was a major shareholder in Recess Screws Limited established at Gillingham, Kent England in 1913. P.L went overseas in 1912 to set up operations and showcase the new screw to the British Industrialists. Once operations were set up, P.L returned to Canada.
Soon after the Recess Screws became increasingly involved in war production, and by 1917 it became a controlled establishment under the munitions war act. To replace male employees who were called to fight in the war and female labor had been hired whenever possible. Recess Screws employed about 400 employees at the British plant by 1919.
The plant produced firing pins for hand grenades and trench mortars, fuse needles and detonating shells, guide pins used in shell fuses and gas checks screws for grenades. Throughout the war they produced almost 55 million units. Eventually the English plant was taken over by the government and P.L resigned as director of Recess Screws Ltd.
After his return to Canada he decided to enter the Untied States market - he approached Curtis Screws Company of Buffalo. After first round negotiations, P.L was frustrated and decided to pass on the opportunity as they could not reach an agreement.
His third major attempt involved the Ford Motor Company. From early years of the Milton plant Ford Windsor accounted for a substantial part of Robertson’s production. By using socket head screws Ford made a considerable savings of $2.60 per car.
This savings captured the attention of the Detroit bosses and soon after P.L was in Detroit talking about expanding socket head screw production to supply all U.S. made Ford cars. Henry Ford refused to commit to a new product line without having a say in how and where the screws would be made. P.L was not happy with this idea and headed home. This meant P.L was letting go of vast potential in the U.S. market, this also included Ford Windsor which accounted for one third of his output of screws.
In 1932, P.L Robertson took off a few years to write a book on how to solve the world economic problems. The book was called “World Reorganization or Downfall and The Remedy”.
Later, P.L succeeded in developing an international market for brass screws and following this P.L concentrated on exclusivity on selling screws in bulk (kegs) to industrial customers. Firms paid a premium price for quality screws. For Robertson, this became a standard in both Canadian and International Markets. His next steps focused on business change to selling to more specific markets, electrical, furniture manufactures and automotive suppliers, etc.
In time, P.L introduced a new screwdriver to the market, something that only he could call his own. He created a “Handikit” exclusively and donated hundreds of kits to high school and woodworking classes, plant visitors or anyone simply interested in the product.
The market effort of the 1930’s increased sales and by late 1930’s P.L was widely recognized as a major player in the screw business. With almost 200 employees for a small town of 1900 people P.L Robertson became a Milton legend.
During the mid 1930’s, times were tough during the second world war, as P.L Robertson felt the weight of the many hard years, until PL caught a break, the armed services needed tremendous quantities of brass screws and Robertson was there to supply them. In addition, a traveling salesman for Robertson landed a contract where carloads of cadmium plated Robertson combination square/slot drive screws were needed for the plywood mosquito bomber aircraft. This was the largest order ever received by the company.
Around the end of the war PL received a phone call from a change to his financial advisor – PL was officially a millionaire.
By 1945, P.L was 66 years old, and became unwell. No wealth could buy him a chance of retirement. His conditions worsened and PL remained at home for the last four years of his life.
Peter Lymburner Robertson died September 28, 1951.
If there ever was a legend in his own time, P.L Robertson was it! He was recognized throughout the plant and the town of Milton for decades as the most important employer in the community. Two plaques honouring P.L Robertson were placed – one in recognition of P.L’s inventions and manufacturing innovations. The provincial plaque is placed next to the Original Robertson building on Bronte Street in Milton Ontario. The other plaque is at the nearby house where P.L Robertson lived for almost 35 years.
The story of Robertson Manufacturing Company Ltd. continues. In 1953, the directors bought the shares held by P.L Robertson’s estate. They ran the firm for 17 years until 1968 when Robertson became part of a U.S Organization. In early 1968, Robertson established Pan American Screw Corporation. A while later, Robertson Manufacturing Company Ltd. accepted an offer made by a subsidiary of Union Tank Car Co. – Procor Limited. The same year the U.S. based firm purchased A.E Whitehouse Co of Montreal – a long established manufacture of screws, nuts and bolts – eventually changing the company name to Robertson Whitehouse.
Today, Robertson Inc. is owned and operated by The Marmon Group/Berkshire Hathaway Company. Robertson Inc. currently manufactures overseas in China and is one of Canada’s largest suppliers of quality fasteners. In Milton, the location still serves as the head office and distribution centre for Robertson Inc.
- Based on the novel - P.L. Inventor of the Robertson Screw - By. Ken Lamb"