The X and Z axis assembly and Chinese precision

Now that I had all parts here, I could also finish the x axis. I already assembled both x ends in a previous step and put the nuts from the lead screws on them. All I needed then was the 3 LM8U bearings and the original 3D printed x-carriage, 850mm of GT2 timing belt, the two 370(!)mm steel rods and 2 cable ties.
Again I recommend to follow the instructions from Prusa:

Prusa X-axis assembly

Prusa Z-axis assembly

If you wonder why I use the standard 3D printed x-carriage now, and not the CNC aluminium part. Then look into the hot end part 2 post, I explain there in detail that the mont only works for the Titan extruder or Titan Aero hot end, but not for the Titan Aqua.
But I am going to use the Titan Aqua and also not a standard V6 hot end. For more details wait for the next hot end part.

Frist, carefully slide the bearing over the two steel rods and make sure you don't push out any balls from the bearing. The steel rods slide into the aluminium parts and are secured with set screws.

On the x-carriage you first need to press in 4 square M3 nuts.

Then prepare the cable ties in the x-carriage.

As next you can seat the bearings in the x-carriage and secure the upper ones with the cabe ties.

So far so good, I thought. But when I tried to assembly the x-axis to the z-axis I noticed that the lead screws were bending away from each other. With the z-axis tops you can see that there is a huge offset.

So I took the x-axis off again, secured both lead screws with the z-axis tops and took some measurements. I know, a folding rule is not an exact tool, but that was in reach.
The distance between the two lead screws was 332 mm.

The I measured the distance between the lead screw nuts in the x-axis and it was 340 mm, 8mm more.

Then I checked if the holes in the CNC parts were deep enough.

Everything looked ok, so I measured the steel rods. And gotcha. According to Prusa they should be 370 mm, mine were 374 mm. And I guess the other 4 mm are caused somehow by the CNC parts.

I need to cut off 8 mm off both stell rods and my tool of choice was my Dremel tool with a steel cutting disc. Surprisingly I was able to cut off exactly 8 mm off both steel rods with a decent looking cut and ended up with the same length for both steel rods.
I only needed deburring the ends and was able to put the x-axis together again.

Now the z-axis tops fitted perfectly, so I inserted the z-axis steel rods and mounted the tops on both sides. Just the little set screws to secure the steel rods on the z-axis were missing, but I noticed that already when I got the CNC parts.