Ok i found the weak parts on the machine. I gently crash spindle into alu block.

The spindle looks like doesn't move or bent but...
The steel sheet table from machine start to bend and do a concave at it center, due no supports on center, the table is fixed only at corners with steel bars (Rectangle frame without middle support)
Also the two bottom linear guides along with granity structure also start to concave, the linears start to concave and whole granity get pull up as long spindle crash down

Bed does A)
Bottom rails and Y granaty does B)
Ref:


Under Machine:



Video: