1. Can I help you fix a few things around the house today? I have some time on my hands until after dinner.
2. The children will get into trouble if they have too much time on their hands We need to find something to keep them busy.

Synonym: time to kill, have (some). The expression suggests a degree of boredom. Whereas have time on one’s hands means only that one has some free time, have time to kill includes the notion that one is waiting for a future event.