1969 Norwood Trim tag date anomaly's

[70 copo]

After exchanging some PM's I have decided to start this thread myself to properly preserve the topic as searchable where several forum participants had asked questions pertaining to Body Plate data fields that have been observed to contain anomalous or questionable data fields.

The Factory called them Body Plates, the hobby generally calls them Trim Tags, Cowl Tags, or Body Tags.

The following are the questions submitted from the Christmas party thread:

Originally Posted by Mr.Nickey Nova

Here's one. Why were all trim tags in June of 69 at the Norwood Plant stamped (06A)??

Originally Posted by 69LM1

Or April stamped 4L ?

Rich

Originally Posted by rlw68

... and why did 02D get used for the first two weeks of March?? Inquiring minds want to know !

My bet is on the computer fumbling the leap year.

Originally Posted by William

Body tag questions would have to be directed to Fisher Body Production Control employees. They released the order to produce the body, including punching the tag. Chevrolet Final Assembly had nothing to do with the tag, never looked at it.

02D tags were built into March; there was no 03A for some reason.

Original thread is located here: https://www.yenko.net/forum/showthread.php?t=169828

[70 copo]

Given the numerous questions on what is basically the same general topic, I decided to explore for an answer in advance of the Christmas party, and the replies that I got were as follows: From the key punch ladies, "We keyed in what we had from the option sheets, what the machine spit out in the form of a completed punch card- well that could be a different story, and we did not have time to look or audit, that was done elsewhere"

From the Data processing guy: All these issues sound like defective switches in the key punch tabulation machine or more likely a punch card reader error .

This is a model 29 card punch station as used at Norwood from 1965-1972:

[70 copo]

Here is one of the punch cards generated by the key punchers. This card takes all the build content of the vehicle order and places it on this card in a form of punch code that can be deciphered and then re read by a card reader. The reader can then rebroadcast portions of the main punch card data as often as is needed for scheduling purposes. For the purpose of this discussion I will confine the topic to the body plates.

[70 copo]

Video is instructive:

[70 copo]

An additional source of error could also be a root programming error where the root data fields are improperly applied for the root batch, meaning the programming spool created for the production period contained a error carried forward and maintained until detected or a new programming spool was created.

Another excellent video:

[70 copo]

Programming Spool:

[70 copo]

So what I am saying is if the program spool (drum) is improperly formatted then the error will be a constant, meaning if read by a reader it will be reproduced as an error carried forward.

The key punch machine by its self was prone to errors also. These were related to internal switch failures which would conspire to punch nothing at all, punch the wrong character, or punch no character at all.

Finally the reader had the same error pretext meaning that the error could be at the reader and the reader only- at the point in plant where the Body plate was being read and then the data transmitted to the Graphotype where the Graphotype then punches the plate with an error.

So what do we have? Like almost everything else simple human error. or failure to properly maintain the system. (Again root cause is human error)


Drum programming at the key punch (human Error)
Defective switch at the key punch (Maintenance Problem)
Key Punch error (human Error)
Read error at the graphotype key card reader (Maintenance Problem)

The consensus is that an incorrectly coded "bad programming drum" is the most likely cause of these batch anomalies.

Ken Shirriff is a wealth of knowledge on these machines the following describes the problems and complexity of how these machines worked along with the various modes of failure.
http://www.righto.com/2017/12/repair...-keypunch.html

[AnthonyS]

Very interesting. Thanks for undertaking this!
Anthony

[Keith Seymore]

Thank you, Phil.

Good information, which I'm sure transfers to other assembly locations and GM nameplates (….like Pontiac!).

K

[William]

Another Norwood body tag anomaly involves standard trim converts built as of March 3, 1969. No more X44.