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Blog posts of '2013' 'November'

SCOTOPHOR LIKES CRISPS TOO!

Our Sphynx cat Scotophor loves crisps and here you see him munching on a nacho cheese tortilla chip : -

I have however saved the best for last because THIS is the brand; -

Some of you may also be aware that a scotophor is not just a rather different cat name but also a tenebrescent material in the presence of strong radiation - indeed, just like your photochromic sunglasses .   Scotophor tubes were initially developed by Telefunken, Germany for use in plan position indicators (PPI) and other specialised military displays and some adventurous manufacturers use them where a persistant display is required in specialised oscilloscope and other displays.

HMV LISTENING BOOTHS, CHAPS ONLY!

 

A few blog entries back, we had the girls' listening booths at HMV pictured, well, today, we have the chap's side of things. As you can see it was not as swish and futuristic but this doesn't seem to spoil things for the erudite young blades who were listening prior to purchase.

It's interesting that the record decks were perched on the edge of a side table with a handy plate at the end to prevent an accidental bump jogging the whole ensemble onto the floor.    In current times where secuurity is of paramout importance, these would be screwed down firmly with security bolts...... how times have changed.

CHILDREN - I COULDN'T EAT A WHOLE ONE!

Well, after Pudsey bear and the annual BBC Children in Need bash and my mammoth Mullard Blackburn tour blog series I think it is time for a little hilarity.   For those of you whom like me couldn't eat a whole one, here's something that may be of interest

 

  

SPEED, EFFICIENCY & PERFECTION - AIMS THAT HAVE BUILT A MAMMOTH FACTORY IN 16 YEARS - PART 7

I say, we are now on the home straight here with the final episode in our tale of a globetrotting 1950s newspaper reporter's visit to Mullard Blackburn: - 

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 methds 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.

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.

 

 

SPEED, EFFICIENCY & PERFECTION - AIMS THAT HAVE BUILT A MAMMOTH FACTORY IN 16 YEARS - PART 6

 Today's episode..........

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 wonderul design - at the rate of 8000 an hour - beautiful anodes!

Part 7, the final part of this story will be here soon....

SPEED, EFFICIENCY & PERFECTION - AIMS THAT HAVE BUILT A MAMMOTH FACTORY IN 16 YEARS - PART 5

Here we go again - a long newspaper article this - 

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.

Part 6 will be coming soon.........

SPEED, EFFICIENCY & PERFECTION - AIMS THAT HAVE BUILT A MAMMOTH FACTORY IN 16 YEARS - PART 4

 The Blackburn Times factory tour article continues apace........

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.  

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 here we see a lady physicist assembling an experimental unit within the laboratory: -

 

Will it never end?  Part 5 of our story follows soon.....

SPEED, EFFICIENCY & PERFECTION - AIMS THAT HAVE BUILT A MAMMOTH FACTORY IN 16 YEARS - PART 3

 And so the story continues.......

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.

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.  And below we see a photo of 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: - 

 

 

Part 4 of this tale will be coming soon.