Hepolite: Precision in the making

This is a blog based around a second edition of the Hepolite brochure.

This 135 page brochure was published by Hepworth & Grandage Limited in the early 1960s and gives an insight and description of the products made. Hepwoth & Grandage were manufacturers of internal combustion engine components and were situated in and around Bradford, West Yorkshire. They formed part of an elite group of companies known as AE or Associated Engineering Limited.

A selection of Hepolite products

The four plants employed in the manufacture of these internal combustion engine components, together formed the largest manufacturing unit of its kind in the world. A total workforce approaching 5,500 produced the most comprehensive range of pistons, rings and liners available throughout the world.

Hepolite plants in Yorkshire

When reading the brochure it is wonderful to note that everything was done in-house.

From design to drawing office, from pattern shop to foundry and from heat-treatment to inspection, every stage required to complete a component was done within those factory walls. This required a highly skilled workforce, especially in the areas of Design & Drawing Offices, Pattern-making, Jig & Tool Rooms and Inspection Department.

I quote: “By the deft use of tools, by sheer craftsmanship and experience, Hepolite pattern-makers create in wood, plastics and metal an extraordinary variety of patterns, many with the most complex of contours. This craftsmanship lies at the root of all Hepolite production and on it depend the success of all the highly mechanised processes which follow.”

Pattern making

The foundry is an early and key stage of component manufacture.

This facility has continually expanded over the years and at the present time has a weekly output of some three hundred tons of finished castings. Several years ago the company took out a licence with the International Nickel Company to produce spheroidal graphite cast-iron, which is now being used in the production of many engineering castings for the motor and other industries. A centrifugal casting foundry was opened in 1938 and has been developed continuously ever since. This section employs considerable mechanisation, the metal being melted in high frequency induction furnaces and the plant operates both day and night.

Piston ring foundry

The large scale manufacture of pistons to suit all different types of internal combustion engines, compressors, pumps and hydraulic units in use today is a vast problem. Quantities may vary from a single unit, to thousands of a single design and in a minimum of five oversize options. In the production of these pistons, conventional machine tools are used for the straightforward operations, but the more complex and specialised machining is undertaken on equipment specifically designed and built by Hepolite engineers. Each process is almost entirely automatic and carried out on modern or special machine tools under very close control, meaning an unusually high degree of precision and uniformity are achieved.

Piston machining department

Now here is a most telling chapter; the Apprentice Training School.

Again I quote: “The cry in the engineering industry has always been for young men, properly trained, to keep British industry in the forefront of world development. In building the Apprentice School and equipping it with the finest machines of their type, Hepworth & Grandage have made a valuable investment. For the apprentices trained there will provide the future craftsmen, technologists and managers to operate our factories in Bradford, Yeadon, Saltaire, Leeds and Sunderland.”

Well said.

Apprentice school

So after a day packed with enterprise and hard work, what happens in the evening you ask? The Sports and Social Club of course. If a member of the Company wishes to take part in some strenuous pastime, he has football, cricket, table-tennis, swimming and Judo from which to choose. If however his pastime is of a more relaxed nature, then it’s off to the club for a game of billiards, darts or chess. All of which can be enjoyed in the pleasant surroundings of the fully-licensed club-house.

"A half of bitter please"

At this period in time Hepolite were undoubtedly world leaders in the design and manufacture of pistons, liners and associated components. They accepted this responsibility very seriously indeed and promoted good practice and custom at every available opportunity. Below is the fourth edition of their Service Manual, published in January 1961.

This is a very concise and well described 128 page manual relating to both general good practice and the use of their components in internal combustion engines. As they were selling a quality product, it was clearly in their interests to ensure these were correctly selected and fitted at all times. Reputation was paramount to Hepworth & Grandage and they went to great lengths to ensure that things were done correctly, both during manufacture and in subsequent fitting by an outside contractor.

This is where King Hep had his say…..in all cases however trivial, be thorough and DO THE JOB RIGHT.

King Hep

Hepolite clearly realised the value of publicity and were actively involved in many forms of motorsport. From providing ‘one-off’ pistons for development and experimental engines, to proving sponsorship to those riders and drivers that used their products on race tracks around the world. 

Alistair King's badges

As motorsport is a fiercely competitive discipline and with those involved constantly seeking an advantage or gain over their rivals, engine builders and ‘tuners’ would not wish to make the results of their efforts known. In supplying unfinished pistons to these teams and individuals, Hepolite were able to claim credit for their product and yet the ‘tuners’ were able to keep their modifications a secret. It clearly worked favourably for both parties and most of the top runners would work with them in this way.

Partly finished and used Manx Norton pistons

Unmachined and as used piston crowns

Sadly the great firm of Hepworth & Grandage Limited no longer exist. In 1983 they became Extrudex Products Limited, then in 1989 AE Piston Products Limited before finally closing the factory gates in 2002.

So what of Helpolite now?

Wassell Limited bought the ‘Hepolite’ tradename from the Federal-Mogul Corporation in 2011 and started selling‘Hepolite’ pistons manufactured by Jieh Chueng Industrial Co Ltd in Taiwan. This is a company specialising in aluminium casting and precision machining, the pistons they produce commonly go by the name of JCC.