This is a spoolmount using 4 bearings (Ø8mm inner diameter). It fits the alu-frame of 6 mm, just snap it on at its stable enough. No screw, bolts og nuts needed - simple and effective!
The inner slide is 6.16mm so it will fit the best if the frame is painted, meaning that the frame might be 6.15 mm.
Files can be mailed - Solidworks files either as .STEP of .prt. Please contact me in comments or my email: c.sigshoj (AT) gmail . com
I recommend ABS and 50 % infill, they'll be strong and nice.
Sorry for the poor pictures. It was taken at night with a flashlight for lighting and poor phone camera.
Attributions to this design:
David Gardner has design some clips for further securing the spool, if the fit is not tight enough. His design can be found here: