8 Jul
2005
8 Jul
'05
7:30 p.m.
From: ard at p850ug1.demon.co.uk
Hi Tony
I'm proposing an experiment for you since I know that
you are the type that would actually try it.
Get two pulley or spools ( like from thread ) that are the
same diameter. Place these on shafts that give you
a few inches between outer edges. Get a rubber band
that is large enough to go around the two spools,
with some tension. Mark the spools with an arrow so that
you can see how fast each rotates. For convenience, spools
should be left and right.
Now place a little drag on the left spool while pulling
the rubber band from the lower span of the rubber band,
towards the left.
This would correspond to how the tapes are in the cassette.
Although, the spools are the same size, I've only done this so
that the surface speeds of the spools would match if a rigid
belt were used, similar to the tape surfaces.
As you pull the rubber band, you'll notice that the right
spool rotates noticeably faster than the left spool, even though
the rubber band is not slipping on the left spool.
This demonstrates the principle of the way the cassette
works ( or at least should ). I do hope you try it.
Dwight
On Thu, 7 Jul 2005, Dwight K. Elvey wrote:
Yes, but remember the belt drives the outide of the tape on the 2 spools.
Yes, the smaller spindle will turn quicker (more revs per second), but
to tension the tape you need to move the tape faster (more inches per
second) on the takeup side. And I still don't see why this happens.
-tony
I'm not sure how it works. The 10% number is
not even
close. It is more like 0.5% or so. It does take up slack
over time. I think it has to do with the stretch of the
belt. There is more tention on one spool than the other,
making one side move a little faster than the other.
The one spool getting the more stretched belt would tend
to move a little faster than the side without stretch on
it since it would see more effective belt movement.
I would think that the faster spindle has a smaller diameter than the
slower one.