Hi workshop,
Im painting cathedral ceilings and theres one main cross beam in a walnut stain which is really nice but the beams coming put from the centre to the sides are pine with an orangey stain that are splotched with ceiling paint and have rills on all timber faces (see photos).



How would i go about staining the pine to be the same walnut colour and remove the paint within the rills? Would i just have to sand? And what would be the best type of sander to use if I do? I dont have much experience with sanding so any suggestons would be really appreciated.
Thanks so much
Celia