Smartrapcore ALU Header Re Design

https://youtu.be/uLWtsCXlBv4

I Re Desing the header of Smartrapcore ALU 3D Printer

1.You don't need LM6LUU anymore. Just use 4 LM8UU.
2.Modify the design of the fixed part of the belt, make it more solid and easy to use
3.Widen the hole of LM6LUU to easier to insert.

Smartrapcore ALU
https://www.thingiverse.com/thing:1007070

Smartrapcore ALU Header Re Design
https://www.thingiverse.com/thing:2573516

FilamentHolder for Smartrapcore ALU
https://www.thingiverse.com/thing:226159