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red750

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The Ford thing was more a control of tolerances than an assembly line concept, simply. A number of dismantled new cars were randomly re assembled and just ran perfectly. as a public demonstration not because they were unduly loose but because they. had CLOSE tolerances of dimensions. They also used exotic steel alloys (with Vanadium) for crankshafts and axles giving small but strong components. Most British  and German stuff was individually assembled, much slower and variable depending on the skill and application of an individual. with   a  later parts fitting issue if a case had to be replaced which was originally an assembly and machined as such. A "NEW" one doesn't line up.. Ford also developed Foundry (casting) techniques far better than many competitors  with more expensive cars. Fords One piece V8 side valve block for 1932 was  quite remarkable and the Lincoln V12 a few years later even more so for its coring excellence and complexity..  In my early mechanical days I hated Fords but didn't know much about how they went about things.I'm less biased now that I've learned more about making stuff. Not just admiring polished aluminium tappett covers and the obvious LOOK things. Nev

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There's no doubt that Henry basically perfected the concept of the assembly line, but my comment was that he did not invent it. 

 

As for mass production, that must have been a common feature of industry long before Henry included it in motor vehicle production. You have to remember that it was early days in the automotive industry and other manufacturers were still following the coach building methods of ages past. Just look at any other mass produced machines of the 19th Century. Colt Firearms is a prime example.  Colt was the first to widely commercialize the total use of interchangeable parts throughout a product. It was a leader in assembly line practice. It was a major innovator and training ground in manufacturing technology in this decade (and several after).

https://archive.org/details/englishandameri01roegoog/page/n226/mode/2up

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It wasn't Ford that invented close-fitting components with fine tolerances and interchangeable parts for vehicles. It was Henry Leland with the Cadillac Motor Company, in 1902.

 

The British RAC got 3 Cadillacs in 1902, disassembled them, and threw all the parts in a pile. Then they randomly grabbed parts, and rebuilt the 3 cars, and drove them away. The engineering world was stunned to see this.

 

Previous to that event, all parts were rough-finished, then hand-finished to make them fit. Henry Ford and other manufacturers picked up on the precision fit, which is what led to mass production.

 

Cadillac have been leaders in engineering fit, finish, and top-grade materials, since before WW1.

 

In WW2, Cadillac was the only company who had the ability to build superchargers and turbochargers for aircraft, which required incredible preciseness of finish, and the ability to balance parts to tolerances previously unknown.

 

https://books.google.com.au/books?id=kK5jDwAAQBAJ&pg=PA177&lpg=PA177&dq=Cadillac+interchangeable+parts+1902&source=bl&ots=80ODoxDt81&sig=ACfU3U3-e-poPRucHTu7qAUSXKCoOviAZw&hl=en&sa=X&ved=2ahUKEwiAusTTh8LqAhXP4jgGHcT7Ae8Q6AEwDHoECAsQAQ#v=onepage&q=Cadillac interchangeable parts 1902&f=false

Edited by onetrack
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Another important element in the success of mass production and the assembly line was the use of Gantt charts. A Gantt chart, or harmonogram, is a type of bar chart that illustrates a project schedule. This chart lists the tasks to be performed on the vertical axis, and time intervals on the horizontal axis. The width of the horizontal bars in the graph shows the duration of each activity. Gantt charts illustrate the start and finish dates of the terminal elements and summary elements of a project. Terminal elements and summary elements constitute the work breakdown structure of the project.  Gantt charts also show the dependency (i.e., precedence network) relationships between activities. Gantt charts can be used to show current schedule status using percent-complete shadings and a vertical "TODAY" line as shown here.

 

In the following tables there are seven tasks, labeled a through g. Some tasks can be done concurrently (a and b) while others cannot be done until their predecessor task is complete (c and d cannot begin until a is complete). Additionally, each task has three time estimates: the optimistic time estimate (O), the most likely or normal time estimate (M), and the pessimistic time estimate (P). The expected time (TE) is estimated using the beta probability distribution for the time estimates, using the formula (O + 4M + P) ÷ 6.

Activity Predecessor Time estimates Expected time (TE)
Opt. (O) Normal (M) Pess. (P)
a 2 4 6 4.00
b 3 5 9 5.33
c a 4 5 7 5.17
d a 4 6 10 6.33
e b, c 4 5 7 5.17
f d 3 4 8 4.50
g e 3 5 8 5.17

 

Pert_example_gantt_chart.gif

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Ok, then without jumping into Google, who created the PERT Weighted Average formula that is used in schedules to assign contingency to the degree of risk in schedule activities...remember this area is my domain

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I reckon Nev's comments about interchangeable assembly were on the mark. This was the turning point for mass production and without it we would be back in poverty.

The geometry and maths for understanding  interchangeable assembly is impressive. These days, we think nothing about buying a spare part and knowing it will fit.

The trade "fitter and turner " indicates how getting parts to fit used to involve modifications to the parts themselves.

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Cadillac still had 3 piece blocks long after Ford made then in one piece and a sidevalve block is double the complexity of an OHV with separate heads .Working out who was first at anything requires a more tight definition of what you are considering. . You have to compare like with like.. An  02 Cadillac is a single cylinder thing with a copper water jacket and a drip oiler.. Ford had his own apprentice training schools with their own books. I've also worked on early Daimler Benz's with the workers name stamped on the crankshaft. Thing's like that are not mass produced. Later they ALL (mostly) went to codes selected for fit (colours or numbers) to keep "fits" controlled.

  Tolerance and clearance are totally different things. You machine things to within a certain tolerance When something moves it has running clearance. When things are press fitted they have "interference " fit.. Same if they are held in a clamping situation  a bearing will have "crush". (like between two crankcase halves).  Nev

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Ahhh, but Cadillac was the first to have hydraulic valve lifters - in 1936 - when the Cadillac was still a sidevalve V8!

 

In addition, Cadillac produced the first V8 car engine - in 1914! - fully 16 years before Henrys famous first V8!

 

Cadillac also designed and built the Hydramatic automatic transmission - in May 1939. But the Hydramatic went into Oldsmobiles first, because Oldsmobiles sold in much larger numbers - and GM wanted to see if there were any "bugs" in the Hydramatic, before they offered it in the Cadillac, to protect Cadillacs reputation for superior engineering.

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And all this fantastic development during the 20th century and consolidation into 3 major companies has now been undone by corporate and individual greed of the capitalist system so now all the best manufactured stuff comes out of Asia & GM, Ford & Chrysler are shadows of their former selves with Boeing heading down the same path.

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On 10/07/2020 at 5:50 PM, Admin said:

who created the PERT Weighted Average formula 

Would you believe that I used Firefox?

 

PERT was developed in the late 1950's for the US Navy's Polaris project. http://www.netmba.com/operations/project/pert/#:~:text=The Program Evaluation and Review,required to complete a project.

 

Probably and important part of using the PERT system is the determination of the Therbligs involved in the production of each component.

 

Therblig - look that up in your Funk and Wannells

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According to my Funk n Wagnalls.....

 

"Therbligs are 18 kinds of elemental motions, used in the study of motion economy in the workplace."

 

Now, I've worked in a lot of different workplaces, but I've never seen an actual, live Therblig. There might have been the occassional small furry creature seen in the staff canteen, but I'm sure it wasn't a therblig.

Nor have I observed 18 different kinds of elemental motions. Our toilets were kept very clean!!

 

Edited by nomadpete
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Cadillac was GM's top model and always very expensive. Ford was for everyone and the cheapest priced car outright. Really not fair to make a comparison without that consideration high lighted. Ford also built the Liberator Bomber in large numbers, during the war, and a vast number of JEEPS under licence from Willy's.. Nev

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On 10 July 2020 at 5:26 PM, old man emu said:

...Some tasks can be done concurrently (a and b) while others cannot be done until their predecessor task is complete...

Thanks for that bit of ammo, Nev. It might help me finally convince my missus that I can't finish building the verandah until the other bit is done...

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On 10/07/2020 at 5:26 PM, old man emu said:

Each task has three time estimates:

1. the optimistic time estimate (O),

2. the most likely or normal time estimate (M),

3. the pessimistic time estimate (P).

 

The expected time (TE) is estimated using the formula (O + 4M + P) ÷ 6.

Ian might call it the PERT Weighted Average formula, but to me it is the mathematical representation of Murphy's Law.

 

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Back in  the day, when I worked for the Commercial Bank of Australia Ltd, I spent some time doing PERT charts to co-ordinate integration of the CBAL's Burroughs systems and data with the Bank of New South Wales IBM systems (Cobol to PL/1) when the banks merged to form Westpac. Don't remember a lot aboout it, (it was 1986). I know it was run on a British computer at a bureau and the charts were printed out on a large blueprint printer. The boss flew down from Sydney each week, would review the charts, and deploy analysts and programmers where needed to keep the integration ontrack. 

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Who would have believed this? .....

 

The Federal Govt held a competition to draw up a new Australian Flag in 1901.  The competition attracted a total of 32,823 entries.

When the winning flag design was chosen, a review of the entries revealed that five people had submitted almost identical designs.

 

These people were declared joint winners and shared the prize money. The joint winners were:

 

1. Annie Dorrington, Artist, Perth (1866-1926)

2. Ivor Evans, Student, Haymarket, Melbourne (1888-1960)

3. Leslie Hawkins, Student, Leichhardt, Sydney (1883-1966)

4. Egbert Nuttall, Architect, Prahran, Melbourne (1866-1963)

5. William Stevens, Steamship Officer, Auckland, New Zealand (1866-1928)

 

Edited by onetrack
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I think it was stipulated that designs had to be a  defaced British Blue Ensign, hence the limitation and similarity in designs. In the original constitution, Western Australia wasn't included as part of the Commonwealth, but the option was there for WA and New Zealand to become part of the Commonwealth of Australia. Both are mentioned in the description of States as Colonies that may be admitted as States into the Commonwealth of Australia.

 

When I was a kid, it was still common for the Red Ensign to be flown and used in street parades instead of the Blue Ensign, but I think most of that had died out by the mid 60's. Some more trivia - any Australian citizen can fly the blue national flag on a private vessel, but in Britain private citizens are not allowed to fly the Union Flag, only the British Red Ensign. I think it's only military and government vessels that can fly the national flag there.

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