In the Dead Tube manga I found this sentence:
いいでしょ… たまには自分の命を天秤に乗せたって
The protagonist is asking a group of people who usually don't risk their life to participate in a risky game. What is the meaning of 天秤に乗せる? Is it a fixed expression? Considering the context, I guess it could be translated as "to risk, to put on the line", is it correct? Please let me know if you need more context. Thank you for your help!
天秤に乗せる/かける is usually a figurative way to say "to compare the importance (of two important things)". For example you can say 命とお金とを天秤に乗せる, etc. In your case, it may be used in the sense of "to risk (one's life)", but that's not a standard way to use this idiom.
jisho defines 天秤 as "(balance) scales" and 乗せる main meaning is "to place on (something)", so 自分の命を天秤に乗せる probably means "to put one's own life in the balance"
