Exactly

[HopperParticipant @hopper]

Posted by lee webster on 27/07/2022 18:30:08:

I have no evidence of this, but wouldn't cheap-ish pottery items of the 1700s have been mass produced? Make a mould and get thousands of cups and saucers etc.

I think Winchester referred more to modern-style mass production of complex assemblies — guns and sewing machines etc — made from standard-sized parts assembled by semi-skilled operators, and the use of jigs and fixtures to expedite manufacture of such. It became known as "The American system of manufacture" when it was introduced to UK factories, which were still using old non-standardised methods. Apparently Brunell senior's pioneering work at the Portsmith shipyards making rope blocks did not catch on in UK factories until it came back to the them via the USA!

[Ex contributorParticipant @mgnbuk]

My understanding of the history of the introduction of mass production is that Marc Brunel (Isambard's dad) built the first ever mass production facility at Plymouth Dockyard making pulley blocks.

I have a recollection that there was an long running series in ME during the period I subscribed about the machines & methods used to make the pulley blocks, which may have included modelling the machines.

Still got the magazines, so could get details of the issues that covered this if anyone was interested.

Nigel B.

[Nigel Graham 2Participant @nigelgraham2]

I believe the original working models Marc Brunel commissioned to demonstrate his block-making line are in the National Maritime Museum in Greenwich. They were featured in one of the London model-engineering exhibitions a good few years ago.

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PatJ asks about the length of a strip of leather – one of my old text-books mentions one way was to cut a spiral from the sheet, and straighten it; but does not detail how that was done.

I think canvas and rope became the more common transmission-belt materials because they can be made in very long, continuous lengths to much more uniform quality. Hawser-lay rope for power-transmission and bell-ringing is joined by a "long splice" that passes easily over sheaves because it adds little to the rope's diameter – or rather, the circumference by which rope size was specified. I did have a special slide caliper, of hardwood and brass, for this measurement.

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Going back to mass-production methods, a progenitor may have been the practice that evolved in the clock-making trade, wherein one man would make only the plates, another the wheels, and so on. It still relied heavily on individual making and fitting.

Did this idea go back even further though, in armaments? The name "Fletcher" refers to the maker of the "Fleche" on an arrow; its guide-feathers.

[CirclipParticipant @circlip]

Yes Nigel B. It was a series in ME and highlighted both sides of the Atlantic's need for speed of manufacture for war supplies. UK for blocks for warships and TLOTF copy turning of rifle stocks at the Springfield works for the war of independence.

Regards Ian.

[HopperParticipant @hopper]

Posted by Nigel Graham 2 on 28/07/2022 10:21:55:

Did this idea go back even further though, in armaments? The name "Fletcher" refers to the maker of the "Fleche" on an arrow; its guide-feathers.

The Chinese were using crossbows made from standardised parts that could be replaced in the field about 2,000 years ago so perhaps that was the real pioneer?

[SamsarandaParticipant @samsaranda]

I was in the Air Force and in 1967 we acquired Hercules transport aircraft from the US. All seemed to be going well until the mid 70’s when a lot of defects started to appear in the wings of the Hercules, not individual aircraft but the whole fleet. The defects were cracks emanating from countersunk fastener holes that ultimately held the outer skin on the wings, there were a serious amount of defects. At this time I was employed as an NDT Technician and we were tasked to monitor every aircraft and in critical areas on the wings to scan the fastener holes using Ultrasound, the technique we used was very sensitive and could detect cracks in the fasteners hole when they were only about a third of the way up the countersinks of the fastener holes. There were many areas that were scanned ultrasonically and I remember one area required the scanning of 2,000 underwing fastener holes, each hole required 6 scans from different points, a very demanding job. Once defects were identified then repair schemes were drawn up for individual aircraft, which mainly involved removing the fasteners and opening out the hole until the crack was eliminated and replacing with an oversize fastener.

The origins of these defects were the use of mass production, the aircraft were built in Lockheeds Georgia factory when they were at their peak output for the Vietnam war. This meant that they inducted a large amount of unskilled labour to build the aircraft on production lines, the workers were given instructions how to use power tools that set the fasteners used to hold the wing skins on the main planes. The theory was that everything had been produced on jigs that meant when it came to assembly all the holes lined up and the unskilled workers just fired the fasteners that held it all together, only the reality was that a lot of holes didn’t align correctly so the workers just got a drill and ran through the problem holes to line everything up.Being unskilled they did not realise the consequences of making the holes in some cases figure of eight, the stresses of the wings would be concentrated on these irregular shaped holes and hence the defects of cracks forming from these stress raisers. It was an extremely costly exercise to monitor and rectify all these man made defects, however a subsequent problem put this problem in the shade. It became apparent that inside the integral fuel tanks within the wings there was large amounts of corrosion eating away the structures. Apparently it was caused by the products of bacteria living in the fuel in the tanks, it was very corrosive and was eating away the structures. The story goes that that the Americans had warned the British of this problem and it could be avoided by using an additive in the fuel which inhibited the bacterial growth, the Air Force apparently disregarded this advice and used fuel without the additive, the saying goes we couldn’t afford the additive.

Subsequent repair of the wings was deemed not viable and each Hercules had to have new wings fitted at a civilian contractors, the wings were shipped over from the US and because of their size they travelled by ship as deck cargo suitably cocooned from the elements, a very very costly exercise.

At the time that the Hercules were built in the US using contract unskilled labour on their production lines, our aircraft industry was still using time served appropriately trained skilled tradesmen so in all probability the fastener hole problem would never have occurred in British made aircraft.

Mass production can save on labour costs but potentially at what cost eventually.

Dave W

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