Bolt cap for training wheels bicycle

I removed the training wheels from my sons bike, and found these bolts stuck out too far for my comfort. I designed this to fit over the bolt and have flaps that bent slightly but held on tight to the threads. Designed for .28 layer height with three layers for the bottom piece. Printed with a 20% infill, but if it breaks I will reprint and increase.

Edit: after months of use and abuse the top has definitely rubbed off and the tip of the bolt is exposed. The cover still makes a nice rounded surface. I will reprint and increase the number of walls and possibly infill, but 3D filament just won't stand up to cement or asphalt, and will continue to wear. But I feel like it has prevented any injury from those giant bolts!

Since thingiverse is so glitchy I'm moving to printables. Find my new designs here: https://www.printables.com/social/325469-tjdesignco/prints