Stronger MMU2s & MMU3 drum remix using a metal flange.

I've removed the part in charge of linking the drum and the motor axis and replaced it with a metal flange.

EDIT#1: I should have checked before, I just saw the MMU3 is using this kind of flange too :)
 

Unlike MMU3 design, this one does not rely on metal flange screws being tightened into plastic (if I'm not mistaken).

Screwing in plastic is bound to wear off (again, I would say). Instead, they screw into embedded metal nuts and I believe it should be sturdier to tighten a screw in its metal nut rather than in plastic.

You'll need 4 M3*10 hex screws and nuts. I've made holes deep enough to have M3*12 and M3*14 also fit.

Flange ref:
https://www.amazon.com/Coupling-Connector-Coupler-Accessory-Fittings/dp/B08334MFVT
https://www.amazon.fr/gp/product/B0833PTFZM

The headless screws provided with the flanges are really small, and maybe difficult to tighten (could damage the tiny hex key)
You can replace them with regular M3*6 or M3*4 since there is room for its head (see uploaded flange picture)

I wish I noticed this before I mounted mine :) 

I've removed the part in charge of the link between the drum and the motor axis and replaced it with a metal flange.

After which I noticed this is similar to MMU3 design, except I use nuts to tighten flange screws, not plastic.