Hi All,  I think we can only speculate as to why roll manufacturers
made the decision not to glue the left roll flange in place.  Some
of my old rolls have both flanges glued in place.  So, it 'was' done
sometimes.

One logical reason for not gluing the left flange has to do with
temperature and humidity.  Being paper, the roll grows and shrinks
with weather changes.  So, if a roll was made in a very dry climate,
and the flange was glued right next to the paper on the left,
problems could arise when the roll was played in Louisiana, Florida,
or even New Jersey...!  ;-)

Another logical reason involves "knocking" the roll, or tapping the
roll so that the right edge of paper moves all the way to right flange.
The practice no doubt became popular as automatic tracking devices
started becoming less and less reliable -- perhaps because of lack of
maintenance.  Even though it's only a quick temporary fix, it would
allow the roll to be played again with some consistency.

Perhaps in later years, as rolls started wearing out, the practice of
'not gluing the flange' was continued because it became obvious that
looking at the left end of the paper roll was a good way to check the
general condition.  I tell this to my customers all the time: "Save
yourself the aggravation of getting halfway through a roll only to find
out it's ripped.  Pull off the flange and check the paper 'before' you
play the roll."

Maybe it was purely economics.  Anything that reduces the cost of
production makes the product more competitive.

Personally speaking, I'm glad the left flange is usually not glued.
It gives me options... and I like options!  Heck, if I want to,
"I" can glue it in place...  :-)

Just my wandering thoughts...

Musically,
John A Tuttle
Player-Care.com
Brick, New Jersey, USA