When designing a linear motion application, you can either choose to build the unit yourself using separate components or choose a complete unit ready for installation. There are advantages and disadvantages to both, depending on the conditions of the application.
Advantages of ready-made linear units
If you choose to use separate components, you must integrate the drive yourself, something that is already in place when you buy a ready-made linear unit. In a ready-made unit, the drive is already assembled with the linear rail guide, and often the unit is encapsulated which protects it from dust and dirt. The disadvantage is that a complete linear unit is more expensive to purchase, but on the other hand, the assembly time is shorter.
A complete, ready-to-mount linear unit is also calibrated from the start, which means for example that any deviations in parallelism or misalignment errors are solved. In addition to that, you get complete performance data, which you otherwise must calculate yourself.
Advantages of separate components
The advantages of separate components are that you can design your linear unit exactly as you want it. After all, there is a limited supply of ready-made linear units. If you need a very demanding solution, it will be relatively expensive to use ready-made units.
A comprehensive solution with complete units also tends to be quite bulky. If you choose to design it yourself with separate parts, you can create a more compact solution.
Ready-made linear units are often encapsulated, which in a way is an advantage but also one of the disadvantages. As the components are built-in and hidden, it is difficult to see possible dirt and debris. In the wood industry, for example, sawdust is devastating for linear units, and therefore it is an advantage to be able to easily both inspect and clean the included components.
