CR10 Spool holder mount

Hi,

Here is my contribution for the CR10 spool holder.
I used this project as a basis: https://www.thingiverse.com/thing:3014266 and this one for fixing the support on the frame: https://www.thingiverse.com/thing:2740042

I added a double threaded insert in order to:

- use the nut provided with the original CR10 spool holder and avoid adding a screw.
- to be able to print the whole thing without support

The addition of a large nut secures the coil on the arm.

Hoping that this will be of service to you

Be careful, the thread entering the arm is a left-hand thread to avoid loosening when the spool rotates.

UPDATE _V3
I have decided to make some changes to version 1.
I found that the nut was not very stable once screwed on because it was not sufficiently caught in the thread of the arm.

In this version 3, I modified:
- The length of the arm and its design
- The design of the moving part
- The thickness of the nut.

If you decide to print this version 3, als