MGN12H Mini Linear Rail Guide, 250/300/ 400/500/ 550mm Linear Sliding Gide with MGN12H Carriage Block for DIY Printer and CNC Machine (250mm)

Product Information

Linear rails with a square section, such as Hiwin guideways, are the first choice when accuracy and reliability are needed. They are the standard on CNC machines and have been gaining popularity in hobby 3D printers and laser cutters as well. Having a higher preload is a benefit for our use case, but does change the way that rails feel when move by hand. What to expect: Dynamic load (C) is the maximum continuous load applied to the bearings and raceways that doesn’t compromise the service life of the rails beyond the nominal rating (which is 50km for MGN/HG rails and other ball-type rails).

Aside from linear rails in the highest price tiers, all linear guide rail carriages will benefit from a proper cleaning before being put into service. See here for a great walk through on this process.However, V-wheels need to be carefully tightened with a small wrench, and require maintenance as they loosen and wear out over time. V-wheels are very much a “save now, worry later” solution. Still, when properly installed, they do provide good accuracy.

Z1 commands a higher preload between the rail and carriage than a more typical Z0 preload. Preload occurs after all space between two components (in this case the rail and carriage) is closed. Any further interference becomes preload, as these materials are too hard to physically compress. V-wheels are the main alternative to linear rails in the hobby space, and are widespread in 3D printers and budget laser cutters (like some variants of the K40 laser cutter). V-wheels are designed to ride on V-shaped grooves of aluminum extrusions. Because of this, they are extremely cost effective for large machines since parts of the frame also act as linear guides. As mentioned before, HG carriages are taller to accomodate four raceways instead of two on the MGN series. This makes them a good choice for heavy load applications like CNC milling, and according to Hiwin it also makes them suitable to be mounted onto slightly uneven surfaces. The open-source PrintNC CNC router design takes advantage of this by using HGR rails on rectangular steel tubes instead of aluminum extrusions. Note: I have only included specs for the short CA/CC carriages, as the HA/HC carriages are much harder to find online. Tips on buying, using & maintaining linear rails Handling Rails can be cut to any length using an abrasive cutting method. Consider graduated shallow cuts to keep heat down and avoid warp potential. Some folks prefer to mount the rail to spare extrusion which can also help with warp mitigation. What is a Z1 preload?According to Hiwin’s official lubricating instructions , these are the recommended grease lubricants for standard applications: Manufacturer