This is full video on how to build CNC machine at home. This CNC mill is very rigid it has very high accuracy. It has zero backlash.

Here are some info on build.

Build time: About 500 hours.
Build cost: About $4500

Travels:
Z : 11" ( 27.9 cm )
X: 22" (55.88 cm)
Y: 12" (30.48cm)

Spindle:
5.5 KW ATC BT30 18000RPM from Ebay. ( very happy with it) seller is super nice guy.

https://www.ebay.ca/itm/Combo-ATC-too...

Electronics:

BOB: PMDX 424. https://www.pmdx.com/PMDX-424
Spindle speed control: PMDX 407. https://www.pmdx.com/PMDX-407
Stepper motors : Nema 34 1275oz-in
Drivers: DM860d from Ebay

Software:
Mach4.
https://www.machsupport.com/shop/mach...

Rails:
20 mm Raills for X,Y and Z

Ball screws:
Y ball screw is 20mm
X Z ball screws are 16mm

Couplings:
Bellows style Ruland coupling with zero backlash .
https://www.ruland.com/servo-coupling....

Frame:
Y Axis
24" x 14" X 4"( 64 X 35.5 X 10.1 cm )
Material 1.25" X 4" ( 3.1 X 10.1cm )steel

X Axis
35" X 11" ( 88 X 28 cm )
Material .500" (12.7mm) base plate
1.25" X 3" walls

Z column
35" x 8" X 4" ( 88.9 X20.3 X 10.1 cm) tube with .500" (12.7mm) wall thikness
filled with cement.

Enclosure:
Aluminum sheet and angle.