For regular maintenance on the Z-axis for your Saturn, please refer to below:
Tools you need:
1. Spray the rust-remover spray on the part that need to be cleaned, and then wipe those off with a dust-free cloth to remove the rust.
Caution: Do not wipe with a cloth made of other rough materials to avoid damaging the surface of the rail.
2. After the rust is removed, apply some zero-viscosity grease(lube) to the surface of the linear rail with a brush and spread it slowly amd evenly.