more on cups
the hard plastic cups make a shinier sparkleball. The joints you melt will cool faster, so you can work quicker. But these cups also make a brittle, more fragile sparkleball.
why not try colored plastic cups? If you do send photos so I can see. Ellessu and Cheri use Chinet Crystal-Cut Cups. Their sparkleballs are the sparkliest I've ever seen. Cheri also recommends that Sam's Club has the best deal on cups.
I heard of somebody dipping the cup rims in glitter before they made the sparkleball.
for the mini-sparkleball, you need 1 oz condiment cups with slanted sides. you can find these at food supply outlets. Also you can use communion cups. (I don't think God will care.)
the softer cups with raised rims make a stronger sparkleball.
make sure the cups have slanted sides or your sparkleball will not be round.