I’ve given Carl Boro a lot of credit on this site, and no wonder. If anyone knows about building sparkleballs, it’s Carl. Probably his very best tip is the 1/2″ step drill bit. Carl uses the bit in a drill press. (video here) I use mine in a hand drill. The bit costs about $14, but it makes absolutely perfect holes. Lights slip in, and they stay put. You can drill up to 4 soft cups at a time. And I’ve stuffed as many as 4 lights in a single hole, although 2-3 works best.
A regular 1/2″ drill bit works just fine if it’s sharp enough. Use a knife and cut x’s in the cup bottoms. Or a soldering iron to melt holes. Any hole is better than no hole! So just do it. . .like the man in Canada who put holes in his cups with a screwdriver he heated up on the stove top :) A sparkleball is very forgiving.
helpful DIY how-to posts:
– find the right cups
– tips for inserting lights
– the best stapler
– how to hang it – 1
– how to hang it – 2
– how to hang it – 3
– using different lights – 1
– using different lights – 2
– drilling a perfect hole
– how to get it really round
– painting the cups
– make The Original Sparkleball
– make AnyCup Sparkleball
– making Mini Sparkleballs