Rail replacement is actually quite easy, though it should almost never be necessary. Rods are held in by a set of host clamps. you will need a replacement rod and a 1/4 inch socket wrench. A flat head screwdriver will also work but is more difficult to work with.
- Loosen front host clamp.
- Slide rod halfway out front of printer.
- Loosen rear hose clamp and completely remove rod.
- Insert clean new rod through front of printer.
- Add first hose clamp oriented as shown below.
- Slide rod through carriage then add remaining hose clamp.
- Tighten rear hose clamp leaving between 1/16" and 1/8" extra space at end of rod.
- Press rod into rear mounting hole of frame.
- Simultaneously push rod towards rear of frame, hold the hose clamp clamp firmly against the front of frame, and tighten clamp.