read this - it depends on the particular shellac, how it was applied, and how old it is .... but in any case, shellac is pretty easy to touch up, although it would be a pretty unusual finish for bed wood
"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir "When we tug a single thing on an old truck, we find it falls off" ~ me Some TF series details & TF heater pics