I go through those re-usable plastic to-go cups with the re-usable straws way too frequently. I love drinking out of a straw, so I prefer using the cups, rather than those sporty thermos things with screw-on lids. I leave them in my car, at work, under seats in doctor's offices... and anywhere else you could think of.
One day I needed a to-go cup, but I couldn't find one. My dad was over, so I gave him this idea I'd been toying around with for a while:
He took my lid, asked me if I wanted the hole in the center or off to the side.
"Off center," I replied.
He walked next door to his house and came back about 15 minutes later with this:
My smoothie was ready to go by the time he got back
It was so perfect, I handed him a smaller jar's lid, so I'd have size large and size small.
So how did he do it?
He made the hole using a drill bit. He said it worked best to start out small, and then gradually make it bigger. Then he sanded the hole with fine sandpaper so the sharp edge didn't have any rough spots. It's still a sharp edge because of how thin it is, so you don't want a little kid sticking their finger in it or anything. I've seen people use food-safe glue and a washer to eliminate the sharp end, but I'm really not too worried about it. Ivy's not curious like that or prone to getting hurt.
I do have reservations that rust might form on the lid somehow, but it's been a good 2-3 months and the hole is still in tip-top shape. We don't have a dishwasher, so the lid gets hand washed and air dried after every use.
Tip #1: Handyman dad's are the best.