Optimized spool holder

I used Toranado3D's wall mounted spool holder. Then I used Cort's customized spool hub. I designed some blocks that will slot into the spool holder instead of PVC pipe. The blocks have a hole for 8mm rod. I set the ID of the spool hub to 16mm for a 8x16x5mm bearing. I then designed a back plate to use as added support to mount on the back of my Da Vinci 2.0a. I used M4 screws that are 35mm long with some nylock nuts and washers on the back side. The arms used six M3 button head screws and washer