If we were not professionals in laser equipment, we would hardly notice how the rails of the desktop laser cutter are running. After a period of use, some laser cutters remain in good working order, while others have bent guides and unstable laser beams.
When a fault occurs, we may feel that this brand of laser cutter is not durable. This does not have a lot to do with the design structure of the laser cutter.
If you have a laser cutter now or are considering buying a desktop laser cutter, you can get a first idea of your laser frame track based on what I have described below.
After continuous development and obsolescence, the rails used in desktop laser cutters are divided into two main categories: linear rails and Linear Bushings. Both are currently used in laser cutter equipment, so let's learn about the differences between the two together.

Linear rail VS linear bushings - What is

Linear rail:

Using a ball cycle, the linear rail moves the laser head on the rail.

Linear Bushings

Linear bushings, also known as linear bearings, are moving structures supported by rails, with the slider moving back and forth on the rails, often used in the 3D printer industry.

Linear rail VS linear bushings - Pros and Cons

Linear rail pros

1. Linear rail for greater precision, with engraving errors within the micron range and precise image matching even with repeated engraving.
2. Low friction between ball and rail for easy movement and long life.
3. Special roller design for greater load carrying capacity. For the desktop laser cutter, you do not have to worry about the rails being bent or deformed over time.
4. Almost no maintenance is required. Only regular lubrication is needed to maintain its long-term stability.

Cons

1. Higher cost, which is why many laser cutter manufacturers do not use linear rail.

Linear bushings pros

1. Easy to install, even if you have no experience in the installation of linear bushings, you can quickly put them together
2. Inexpensive and cheap to maintain afterward

Cons

1. Prone to precision and high tolerance inaccuracies
2. Susceptible to bending the bearings as they have to take on additional parts such as belts, transfer belts, etc.
3. High friction between laser head assembly and bearing, prone to component wear due to rapid operation
4. Easy loosening of the interface between the bushing and the bearing

Linear rail VS linear bushings - Mechanical

Load-bearing capacity

Due to the different mounting and working principles, the linear rail can share the resistance of the load using a special structure. This special structure gives it a higher load-bearing capacity. As the width of the rail increases, the load carrying capacity of the Linear rail is much higher than that of the Linear bushings.

Accuracy

Linear rail is far more accurate than linear bushings, although both are capable of precision engraving/cutting. But more often than not, the linear rail is more stable in its operation and more likely to achieve better parallelism.

Speed

In general, the two have no significant difference in speed. However, the speed of linear bushings will gradually slow down over time due to wear and tear on the belt and motor.

Support

Linear rails are self-contained, more compact, and usually supported by frames and aluminum profiles.
Linear bushings usually require more auxiliary parts and are often supported by aluminum extrusions for easy alignment.

Cost

The same length of the rail, the price of linear rail is about 4-5 times that of linear bushings, and as the length increases, the price difference can be up to 10 times. The main reason for this difference is that the production of linear rail is much more difficult than linear bushings.

Conclusion

If you want a desktop laser cutter, linear rail is your best choice. Because manufacturers rarely advertise this as an advantage of their machines, it has become common for linear rail to be the default configuration for laser cutters. If a desktop laser cutter uses linear bushings, you can use this as a reason for the seller to discount you.