sand down
Intermediate (B1)neutral
To rub sandpaper on something to make it smooth.
"You need to sand down the door before you paint it, otherwise the paint won't stick."
Hear it in context

Parks Cold Opens To Watch Instead Of Escaping | Parks and Recreation
Parks and Recreation · 8:33
I'd rather sand down my toenails.

Leslie Knope moments we LOVE to binge | Parks and Recreation
Parks and Recreation · 15:37
I'd rather sand down my toenails.

Ron Season 4 Moments That Developed My Frontal Lobe | Parks and Recreation
Parks and Recreation · 2:32
I'd rather sand down my toenails.

How to Fix a Sloppy Shifter and Leaking Transmission
ChrisFix · 8:00
we're gonna have to sand down the corrosion

Will Smith Examines Mysteries of Planet Earth | One Strange Rock MEGA Episode | National Geographic
National Geographic · 63:11
But get this: all of that sand down there?