Summary

FilamentChallenge - Easy Spool Holder

Simple to print
Simple to change
Easy to use

Parts that are not printed:
Ball bearings
M8 threaded rod
3mm screws

To get the proper length spacer, use the customizer, but read the instruction first.

Instructions

It is all based on a 8mm threaded rod

Fixed parameters are:
End Caps: 10mm (times 2)
Washers: 3mm (times 4)

Recommended bearings 8x16x5 mm
I recommend that the width between the spacers (bearing width on one side) is a minimum of 10mm.

You can find all formulas and "calculator" in the attached Excel file.

The Excel "Calculator can also calculate a "multi-width" setup.
The idea is to make a roller that can take different spools with different widths.
Key in the narrowest spool and the widest spool and it will calculate the spacer width, threaded rod length, number of bearings extra to use and so on.

Calculations:
Spacer is calculated as follows, Spacer_width=(Spool_width+2)-(Number_of_bearingsBearing_width)-(2Washer)

Calculate the length of the threaded rod using the following, rod_length=(2End_caps)+(4Washers)+(Number_of_bearings*Bearing_width)+Spacer_width-1

FilamentChallenge - Simple Dynamic Spool Holder