It is hard to say what went wrong.
The D cell should make a powerful enough magnetic field as long as you have
several hundred turns of wire all going around in the same direction.
The usual problems have been: People used "magnet wire" and did not clean
the invisible coating off the ends of the wire before attaching the ends to
the battery. You should get sparks when you attach or disconnect the wire
ends from the battery if a good connection is being made.
or they used bare wire and the current took a straght line path from coil
to coil, a "short circuit"
or the battery was dead, put it in a flashlight to test it.
I hope this helps.
Paul Doherty
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