So you're leaving Earth to start a new life on Planet C. The only problem is that grandpa's old Steinway weighs more than the baggage allowance for the entire family. By a lot.
But you can take a nice light portable DP to Planet C instead so that's all right. Right?
Anyway that's the setup for Frank Herbert's 1973 short story "Passage for Piano".
(Herbert doesn't get into it but I'm assuming that the gravity and relative humidity on Planet C must be suitable for the Steinway)