Selectron carrier design flaw & modification

[P3D E R Swanson <ers@xxxxxxxxxxxxxxxxxxxx>]

My friend Ray and I were visiting in Burger King and looking at Selectron
carriers, and he told me about a problem they all seemed to have. They
have springs to keep slides flat to the side of the carrier, but there is
no mechanism to keep the slides level. I cycled the carriers we had on the
table and it was true for both. The right side of the slide (in this case
an RBT) could be pushed down over a millimeter by sticking a toothpick in
the aperture and pushing down. This would put your slides out of level
during a program. Ray had built a little spring loaded push button that
applied force to the top of the slide to seat it flat along the bottom
rail. Ray doesn't normally use a Selectron and after testing the
modification stuck the carrier in the bottom of a drawer where it's been
for some years. It wasn't entirely clear to me how it worked. There may be
other solutions.  Has anyone else come up with a fix for this? When I can
get some more carriers to experiment on I'll work on it. An internal ball
bearing with a weak spring behind it seated and peened into a hole drilled
the metal carrier bar might be an approach that avoided adding any
external mechanical bits. 

Anyway, it made a pleasant lunchtime topic of conversation...   :)


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