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Speed, Efficiency & Perfection – Aims That Have Built a Mammoth Factory in 16 Years

by RF Kennedy

Editors note: This article was first published in the Friday evening editon of the ‘Blackburn Times’ on 12th February 1954. It vividly recaptures the sense of excitement and opportunity felt by the people of Blackburn, Lancashire when Mullard opened their new tube works there. At its zenith in 1962 the works employed over 6200 staff including assemblers, technicians, chemists, scientists and engineers – it was the largest and best equipped vacuum tube research and manufacturing plant in Europe. Special thanks to Steve at Mullard Magic who has very kindly granted me permission to reproduce the copy he digitised here. Steve maintains an informative blog on the history of Mullard with some fascinating stories and photographs – it’s well worth checking out if you’re interested in discovering more about Mullard, the people, the places and the technology that created those now coveted N.O.S. glowing bottles.

Inside Mullard Blackburn works

Lunchtime break at the Mullard Blackburn works.

It was a 40-minute lunchtime break at the Mullard Blackburn works and the rush scene showed hundreds of workers on their toes, determined not to loose one second of the interlude which was typical of a factory where the accent is on….. Speed, Efficiency & Perfection.

To a newcomer, it all seemed so much bustle but a tour of the mammoth factory – I could have stayed all week and still not seen the whole – showed there was organisation behind the bustle.

This organisation has brought contented employment to over 3300 people of Blackburn and district and through the production of millions of valves each year, is bringing untold pleasure to countless numbers of television viewers and radio fans in every corner of the globe.

Yes, Mullard have certainly notched a place for themselves in the industrial prosperity of this town whose bread and butter for generations have been dependant upon the cotton industry. And Mullard have achieved this proud place in the space of a mere 16 years.

After passing through the iron gate at the entrance, I peeped at the foundation stone on the main building. It was dated 1938 and I was later told that Alderman J Fryars then Mayor of Blackburn had made an expert job of laying it.

Looking round at the factory blocks on the 43-acre site, it did not seem out of place to conjecture that such strides could only have been made over a century and certainly not within a decade and a half.

Mullard loomed like a monster cave to be explored and investigated in sections. The assorted processes in the evolution of the valve were so interlaced that to take each one and look at it seperately was almost a crime against the system. So, instead of plunging into the technicalities of valve production, I learned how the factory ticked over and how an army of over 3300 employees were kept marching.

An army they say, marches on it’s stomach so one of the key spots on the tour was the factory canteen where 1200 can be seated at one sitting. An interview with the canteen manager revealed how the 48 strong canteen staff manage to cope in feeding the factory and the daily consumption list is enormous with 1200 to 1500 meals being served comprising of 750 sweets, 40 gallons of soup, 15 cwts of potatoes and 950 rounds of sandwiches and all this washed down with 7000 cups of tea.

Up in the morning early, the canteen staff are on hand to serve a steaming brew to workers on the early shift and so it continues from 06:30 until 22:30 meeting the needs of a steady stream of eager customers. For those who have not the time to leave their benches during the staggered 10 minute breaks, a dozen tea trolleys skim round the various departments with a respectable assortment of cakes and snacks.

In the sick bay, first impression was of the cleanliness of the well equipped rooms. The Sister presiding told of how she and her four staff had dealt with 70 patients before 10 o’clock that morning. Apparently, all manner of cuts, burns and sores are tended at the sick bay. If an employee chances to be troubled by lumbago or gout then there’s a Physiotherapy Deartment with it’s modern heat treatment.

Inside Mullard Blackburn works

Four apprentices, in the age range 15 to 17 setting up a Karger lathe in the training school under the watchful eye of the Head Instructor.

But Mullard is really quite a healthy place, possibly fittest in it’s “baby” section — the Training School. Here, there is full scale machinery for 20 apprentices and throughout the works, some 50 youngsters are being given practical and theoretical tuition. The Head Insructor and his assistant advised that in the school workshop, the boys carry out all sorts of machining and fitting work and that no question goes unanswered.

In yet another section of the works, I found older men who were still learning – highly skilled scientists experimenting with processes on the secret list, all aiming for even speedier and better methods of production. In glass walled rooms filled with weird apparatus was a complicated array of tubes and taps and of course acid carboys, It had been assembled to discover new materials for valve making.

Inside Mullard Blackburn works

Here we see a lady physicist assembling an experimental unit within the laboratory

The Laboratory housed 40 scientists working in a series of areas, subdivided into sections: Analytical; Electrical; Metallurgical; Physical & Glass Research. Here too the emphasis is on hussle plus vigilance. As an example – for analysis the use of chemicals has been superceded by the spectrograph which reduces analysis time from a week to only half a day.

And so to the technical side, valve production is in three parts – metal components come from the components factory; glass pieces and bulbs from the glass factory and filaments and fine wire from the wire factory. Most fascinating of all was the wire factory where I saw how a tungsten bar two feet long was drawn down and stretched until it was 100 miles long to a thickness of 1/10 that of a single human hair.

But that’s not the end of the wonders as the wire was then checked on a super-fine balance which weighs down to 2/100 of a gramme. These incredible dimensions are achieved by passing the wire through diamond dies – between 200 and 250 of them. As the wire passes through each one it is slimmed more and more and each die involves a separate piece of machinery. Each diamond is worth, dependant upon size, somewhere between £2 and £30 with each during it’s lifetime fining down about one million miles of wire. To allow passage of the wire through the dies, the diamonds are drilled with a sewing needle coated with a special abrasive.

In the components factory, cathodes are cut, trimmed and shaped and one automatic machine was capable of reeling off 2500 cathodes per hour and when one considers that only one or two are needed per valve, this level of production represents a lot of valves.

At the end of each bench I noticed a squared sheet headed ‘Quality Control Chart’ where defects can be recorded every fifteen minutes. This scrutiny in the search for the ideal, I found, was the forte of the entire works with 100 people in the factory doing nothing else but inspect the product in its many stages.

One process which proved interesting was the insulation of filament from cathode by coating the spiral tungsten wire with aluminium oxide then a neat gadget gets hold of this much travelled wire and bends it into either an M or V shape. This may seem very complicated but I watched a deaf and dumb boy manipulating one of these machines. He had been taught by a charge-hand purely by demonstration. The wire in this particular machine was cut off at the right length, dropped down into a slot, pushed up into rollers and formed into shape. Then along came a steel hand to hang it on what can best be described as a miniature clothes line.

A partition separated the cathode section from the plant where welding was in operation. Here, anodes were in production with two halves being welded together to form a shape like a miniature fire screen.

While an operator kept a keen eye on all the parts as they moved lifelike, the four slide machine with its many pairs of hands did nine jobs at the same time. The outcome of its activity were a tumbling mass of a minutely shaped things – like a metal snowflake of wonderful design – at the rate of 8000 an hour – beautiful anodes!

In the Grid Department, the grid backbones were being fed through a machine from reels and the tungsten wire, fitted on to a spool was wound around these backbones. The grids, up to now all bound together in one continuous strip, were later cut into single units and connections welded to them in readiness for assembly in the valve base.

The next part of the tour included the Glass Factory where I wished I had discarded my scarf as the furnaces were blazing away at 1200 degrees Centigrade. From the furnaces emerged glass tubing of varying diameter which was fed vertically in an unending cylindrical shape up through two floors to the cutting machines.

After seeing the tubes disappear through the “grill room’ ceiling we then followed them to a part of the factory where the traditional art of glass blowing by power of lungs and skill of eye was neither welcome nor respected. Indeed, I should have pitied the consciencious craftsman who would have the awesome task of keeping pace with the relentless flow of tube from the furnaces below.

Two methods of cutting the tube were in use with the first using a thin band of heat and a cold wheel to effect a break which was then smoothed by application of a flame. A mechanical pair of hands sealed off the end and heated air blew it into the desired size and shape. The second saw a diamond doing the preliminary work finished off by a fire jet. Bases were also being rolled off an assembly line at this factory, the capacitoy of one base pressing machine alone being 2000 an hour.

Inside Mullard Blackburn works

Girls assembling tubes

At last to the assembly unit or Valve Making Department. Here assemblers fit together a 40 or 50 piece jigsaw in a foot operated jig. Some of the jigsaw parts are so small that they have to be lifted from their racks by magnets which the assemblers wear on their hands like rings. The bench layout is so constructed such that left and right hands are kept fully employed. Not an instant is wasted. An electric spark welds on the base in a twinkling of the eye.

On the “ageing rack” tests are carried out under much more severe conditions than the valve would ever experience in Mr & Mrs Smith’s TV set. The valves are now ready for packing and loaded on the long bay at the rear of the factory where a van fleet is kept busy throughout the day. I took leave of my hosts as one of Mullard’s 200 internal telephones summoned them to some distant part of the factory.

Blackburn (Microtech Solutions) went into administration in September 2009. This was the end to a very long era that had begun when engineer Captain Stanley R. Mullard first founded the company in 1920 to manufacture electronic radio (and then later television components). By 2009 a large part of their business was the production of cathodes for televisions however the development of the new flat-panel screens had started to make the cathode ray technology obsolete. Business became progressively more and more difficult and the few workers at Blackburn finally lost their jobs. To add salt to the wound, as well as manufacturing television components, engineers at Blackburn had been developing a new type of vacuum tube for audio amplification, the MicroTech E813CC, which had some geniune improvements over the ECC83. It required lower heater current and the engineers had also put a great deal of time into working with audiophiles and guitarists to get the tone balance just right. The new tube had only been in production for a matter of weeks before the factory closed.

I was recently motivated by sheer curiosity and a sense of nostalgia to travel to Lancashire to explore the Blackburn site to see what, if anything remained of the Mullard plant. You can find photos of my expedition and read my ramblings on the Effectrode blog.