A linear bearing provides low friction motion along a single axis. They are a little costlier than classical round bearings, but simpler to integrate in carriage design.
Some bearings need lubrication to run smoothly. Use white lithion grease, tri-flow or 3-in-1 oil.
Don't use dry lubricants, PTFE-based greases or thick, high tempoerature greases like wheel bearing greese, because they may stop the bearing balls from circulating. Also don't use spray lubricants, as it contains an agent that helps it spray evenly but does no good to precision ball bearings.
Apply the lubricant inside the bearings. If you try and put it on the rod, the brearings just wipe it off.
|Model||Inner D.||Outer D.||Length||Vendors (shipping location)||Additional notes|
|LM6UU||6 mm||12 mm||19 mm||Paoparts (FR)|
|LM8UU||8 mm||15 mm||24 mm|| 3D Maker World (US)
|LM8EUU||8 mm||16 mm||25 mm||Reprapsource (DE)|
|SCS8UU||8 mm||35 mm||30 mm||Paoparts (FR)||With 4x M3 holes.|
|LM10UU||10 mm||19 mm||29 mm|| Paoparts (FR)