Dating ABU Reels
Numbering on ABU reels is a
most challenging topic. it is not fully understood and as soon as a
rule is applied, it is sure to be over-ruled with an exception.
To help us
understand this topic, I will try to summarize here, as simply as
possible what i have observed on my own reels over 40+ years,
discussed with knowledgable collectors and read in books produced by
the top writers of collecting ABU reels.
The two writers I
would recommend to you are Daniel Skupien (1) and Simon Shimomura
(2)and I would whole-heartedly commend you buy their beautiful, most
informative books. I have all 3 in my armoury of useful reading
material about ABU.
Briefly I have
noticed many changes in the numbering systems from my earliest
Records, where often no numbers were engraved at all, through to the
current reels. Of most interest to me is the period from the 50's to
the 80's. I guess the Borgrstom family had no concept at all of how
significant ABU would become over the next 5 decades and little
thought was given to inventory control, numbering models etc as they
concentration was on just making the best!
Starting with the
Ambassadeurs, notably the Record Ambassadeur 5000, they did not have
any numbering system employed at all.
I am informed that
the serializing process did not begin until the Record name from the
Ambassadeurs whence they were named ABU Ambassadeur only.

So then, both the
Record Ambassadeur 5000 and 6000 (wide spool version) released just
a year or so later, had numberless smooth reel seats.
When ABU did start
numbering, it was a serialized form. the first to appear was the
famous ABU Ambassadeur 5000 which has a number like 118158 which
simply meant it was the 118thousand and 158th reel in the series.
Numbers would soon run out, due to world wide popularity.
Around this era ,
two other Ambassadeur 5000 reels , namely the B (still red, but with
Clicker) and C (black with ball bearings rather than bushes) models
were serialized also but were considered different to the standard
red Ambassadeur 5000.

This initial
numbering process ended in 1963 and 1964 saw the start of a new
regime, for all reels except for the Ambassadeur 5000 A B and
C models, which continued to employ the previous method of
serializing until 1971. I am unsure why, but suspect it may
have had to do with these models staying on the original production
line/stamping process, while new equipment may have been employed
for the newer production reels??
So then , now if one
was to observe the reel-foot numbered say 090400
, one could infer it was made in September, 1964 and it was the
first production run before any minor changes were made. After the
sixties ended, the format became 097000 which meant
September, 1970 , first production run of the model without changes.
01 on the end of a number a following design production revision.
There were then more
changes to the numbering process, from mid 1971. It was fairly
simple and just moth and year were reversed so the year of
production were the first two numbers in the indentification string
eg 730900 meaning produced in 1973, September , first run.

All this said we can
find MANY variations to the rules! It is a start. I'm sure a whole
book could be written on the topic an who knows, maybe one will be
forthcoming one day. The difficulty is that many written record of
methods used just do not exist.
I hope to
illustrate more of these markings from my collection when time permits.