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:

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

Or April stamped 4L ?

Rich

... 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.

:rolleyes2:

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:YnnGbcM-H8c

[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: kaQmAybWn-w

[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/repairing-1960s-era-ibm-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.

[CamaroNOS]

Thank you very much for the information Phil.

This will hopefully address some of the questions that have popped up over the years.

Paul

[Mr.Nickey Nova]

Thanks for taking the time to look into this issue Phil, job well done... If anyone else has anything on this subject, feel free to chime in.

[70 copo]

Beyond the most likely cause being the repetitive data spool/drum update data field error there is more. For those of you that want to geek out on all the ways an IBM model 29 can fail and provide erroneous data output just have a quick look at the maintenance manual. By today's standards it is pretty needy. Look at pages 9 through 14 for failure tree diagrams.

http://bitsavers.org/pdf/ibm/punchedCard/Keypunch/029/225-3357-3_29_FE_Maint_Man_Nov70.pdf

AND:

After looking at the outcome to this investigation we have decided to supplement the informational conclusions to the previous 1968 POP thread to reference this thread.

As to the remaining workers that I have befriended from the Norwood Plant I am going to miss these people when they all leave us for good.:worship:

[70 copo]

Amended POP error thread is here: https://www.yenko.net/forum/showthread.php?t=161331

[rlw68]

In 'Echoes of Norwood' p98, there's a picture of the body plate stamping machine connected to a card reader. If the cards were the source of errors they would need to include the Fisher build date. The date, like the plant code NOR and other legal jargon, was most likely set on the machine.

The substitution of a 5 for an N would be one heck of a typo ! :eek2:

208534

[70 copo]

Rob,

Good observation... The repetitive data fields like the date of production week and the plant were on the programming spool (drum). This was to save key puncher time and reduce errors this is called programming driven entry.

If the programming drum for the week has the wrong date or is simply not changed timely that is a factor in batch errors in all the card readers.

Review this video starting at minute 1:38

YnnGbcM-H8c

[70 copo]

Rob,

An error like 5OR is likely a reader error.


Note the warning in this video at minute mark 1.00

kaQmAybWn-w

[jeffschevelle]

Excellent post, thank you!

Do any of the workers recall exactly when (what day of the week) the production week designation advanced to the next letter? And how long did the code for the final production week of a calendar month (such as 02D, or 03D or 03E) continue to be used into the first few days of the next calendar month?

Based on observed tags from Chevelle plants (not Norwood), it appears to me that they did not advance the week designation on the 1st day of a given calendar month, unless that happened also to be the first day of the new production week. For example, I have a 67 Baltimore Chevelle that has a broadcast date printed on the trim card of 12/1/66 (which was a Thursday), but it has an 11E Body Plate.

And that would make sense as long as the first day of the production week was not Thursday. For example, if Wed Nov 30, 1966 was the first day of the E week, you would not expect the plant to reprogram everything on the 30th (to 11E) and then turn right around and reset it all again the very next day to 12A.

That would also explain why it seems like you see far less A tags than D and E tags, if most of the first week of a calendar month is still being coded as D or E of the prior month. Then I would guess they would jump straight to B when the next production week began.
That is just a guess, but it is almost the only way to explain why (at least with Chevelle plants) there are so many months with an E week found on Plates.

If you pick any given weekday as the hypothetical "first day" of each production week, and carry that day all the way across the entire 1965-1967 calendars, you cannot find a weekday that will yield a 5th "E" week in every month that there are E tags existing for. So there HAD to be something odd about how they handled the first few days of each month (unless the first day of the calendar month happened to also fall on the first day of the new production week, which would get an "A" designation).

Thanks again for your efforts! Jeff

[Kurt S]

Excellent post, thank you!

Do any of the workers recall exactly when (what day of the week) the production week designation advanced to the next letter? And how long did the code for the final production week of a calendar month (such as 02D, or 03D or 03E) continue to be used into the first few days of the next calendar month?

Jeff,
Your observations about the plants are probably spot-on. But it's hard to generalize - from what I've seen, every plant handled the tag dating differently. If there was a rule, it wasn't generally enforced.

[70 copo]

Jeff,

At the 2018 MCACN I brought some workers from GMAD Baltimore for a table meet and greet. I will do some asking to see if there is any of the BAL salaried guys that could help and still alive.

These kinds of questions are really in the weeds and It took me literally years to develop the network and trust needed to locate the people from just Norwood with the specific information in order to piece things together - often from multiple sources.

A lot of the information you get is junk or hearsay as well so then you have to verify what is being stated. There is often a language barrier that has to be overcome. For instance If I simply ask about the 1966 Chevy II L-79 I will get blank stares, BUT if I show a photo of the unique air cleaner then I am much more likely to get information in reply.

I avoid single guys that are glib and know everything like the plague, and then if they do produce information I verify it independently prior to putting it out. As an example the Norwood Computer guy provided the information that seemed quite logical and then to verify it I had to gain a working understanding of ancient production computing as well.

SO:

Here are the period specific challenges in getting first hand technical information for the other plants:

BIG Transition period across GM, Some plants were dual division e.g. Fisher Body/Chevrolet. (Dual division/dual Management)

Other plants were already GMAD (single division single Management)

Other plants were still under the old BOP management model (Buick, OLDS, Pontiac)

Other plants also had bodies literally made at a separate location and transported to a different location for Chassis assembly also.

The good news is that NORWOOD also transitioned to GMAD management in 1971-1972 so the operation of scheduling and production is likely very similar to Baltimore.

I will see what I can find but it will likely be entirely hypothetical and based upon a Norwood based theory of operation-- unless I actually find the Baltimore Subject Matter Expert, and that takes much time and TIME is not on our side at this point.:flag: