If you are interested in DIY 3d printer building or learning the mechanism of 3d printer, this tutorial will be helpful for you to understand it.

This video first shows how to assemble the Ultimaker 2 sliding block in detail. And then explains the Ultimaker XY axis mechanism and full assembly process.

I think this tutorial is the only video instruction for assembling the Ultimaker 2 style XY Axis linear motion parts.

You can see full instructions in the link below.
https://www.instructables.com/id/Buil...

0:00 Intro
0:07 Step 1. Parts List
0:50 Step 2. Sliding Block Assembly
3:23 Step 3. Explaining the Ultimaker Style XY Mechanism
5:28 Step 4. Attaching the Components to the Frame
11:51 Step 5. Attaching the Printhead and Shaft
12:56 Step 6. XYAxis Alignment and Fastening the GT2 belt Pulleys